// Copyright (c) 2011-present, Facebook, Inc. All rights reserved. // This source code is licensed under both the GPLv2 (found in the // COPYING file in the root directory) and Apache 2.0 License // (found in the LICENSE.Apache file in the root directory). // // Copyright (c) 2011 The LevelDB Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. See the AUTHORS file for names of contributors. #include "db/version_set.h" #include #include #include #include #include #include #include #include #include #include #include "compaction/compaction.h" #include "db/blob/blob_file_cache.h" #include "db/blob/blob_file_reader.h" #include "db/blob/blob_index.h" #include "db/internal_stats.h" #include "db/log_reader.h" #include "db/log_writer.h" #include "db/memtable.h" #include "db/merge_context.h" #include "db/merge_helper.h" #include "db/pinned_iterators_manager.h" #include "db/table_cache.h" #include "db/version_builder.h" #include "db/version_edit_handler.h" #include "file/filename.h" #include "file/random_access_file_reader.h" #include "file/read_write_util.h" #include "file/writable_file_writer.h" #include "monitoring/file_read_sample.h" #include "monitoring/perf_context_imp.h" #include "monitoring/persistent_stats_history.h" #include "options/options_helper.h" #include "rocksdb/env.h" #include "rocksdb/merge_operator.h" #include "rocksdb/write_buffer_manager.h" #include "table/format.h" #include "table/get_context.h" #include "table/internal_iterator.h" #include "table/merging_iterator.h" #include "table/meta_blocks.h" #include "table/multiget_context.h" #include "table/plain/plain_table_factory.h" #include "table/table_reader.h" #include "table/two_level_iterator.h" #include "test_util/sync_point.h" #include "util/cast_util.h" #include "util/coding.h" #include "util/stop_watch.h" #include "util/string_util.h" #include "util/user_comparator_wrapper.h" namespace ROCKSDB_NAMESPACE { namespace { // Find File in LevelFilesBrief data structure // Within an index range defined by left and right int FindFileInRange(const InternalKeyComparator& icmp, const LevelFilesBrief& file_level, const Slice& key, uint32_t left, uint32_t right) { auto cmp = [&](const FdWithKeyRange& f, const Slice& k) -> bool { return icmp.InternalKeyComparator::Compare(f.largest_key, k) < 0; }; const auto &b = file_level.files; return static_cast(std::lower_bound(b + left, b + right, key, cmp) - b); } Status OverlapWithIterator(const Comparator* ucmp, const Slice& smallest_user_key, const Slice& largest_user_key, InternalIterator* iter, bool* overlap) { InternalKey range_start(smallest_user_key, kMaxSequenceNumber, kValueTypeForSeek); iter->Seek(range_start.Encode()); if (!iter->status().ok()) { return iter->status(); } *overlap = false; if (iter->Valid()) { ParsedInternalKey seek_result; Status s = ParseInternalKey(iter->key(), &seek_result, false /* log_err_key */); // TODO if (!s.ok()) return s; if (ucmp->CompareWithoutTimestamp(seek_result.user_key, largest_user_key) <= 0) { *overlap = true; } } return iter->status(); } // Class to help choose the next file to search for the particular key. // Searches and returns files level by level. // We can search level-by-level since entries never hop across // levels. Therefore we are guaranteed that if we find data // in a smaller level, later levels are irrelevant (unless we // are MergeInProgress). class FilePicker { public: FilePicker(std::vector* files, const Slice& user_key, const Slice& ikey, autovector* file_levels, unsigned int num_levels, FileIndexer* file_indexer, const Comparator* user_comparator, const InternalKeyComparator* internal_comparator) : num_levels_(num_levels), curr_level_(static_cast(-1)), returned_file_level_(static_cast(-1)), hit_file_level_(static_cast(-1)), search_left_bound_(0), search_right_bound_(FileIndexer::kLevelMaxIndex), #ifndef NDEBUG files_(files), #endif level_files_brief_(file_levels), is_hit_file_last_in_level_(false), curr_file_level_(nullptr), user_key_(user_key), ikey_(ikey), file_indexer_(file_indexer), user_comparator_(user_comparator), internal_comparator_(internal_comparator) { #ifdef NDEBUG (void)files; #endif // Setup member variables to search first level. search_ended_ = !PrepareNextLevel(); if (!search_ended_) { // Prefetch Level 0 table data to avoid cache miss if possible. for (unsigned int i = 0; i < (*level_files_brief_)[0].num_files; ++i) { auto* r = (*level_files_brief_)[0].files[i].fd.table_reader; if (r) { r->Prepare(ikey); } } } } int GetCurrentLevel() const { return curr_level_; } FdWithKeyRange* GetNextFile() { while (!search_ended_) { // Loops over different levels. while (curr_index_in_curr_level_ < curr_file_level_->num_files) { // Loops over all files in current level. FdWithKeyRange* f = &curr_file_level_->files[curr_index_in_curr_level_]; hit_file_level_ = curr_level_; is_hit_file_last_in_level_ = curr_index_in_curr_level_ == curr_file_level_->num_files - 1; int cmp_largest = -1; // Do key range filtering of files or/and fractional cascading if: // (1) not all the files are in level 0, or // (2) there are more than 3 current level files // If there are only 3 or less current level files in the system, we skip // the key range filtering. In this case, more likely, the system is // highly tuned to minimize number of tables queried by each query, // so it is unlikely that key range filtering is more efficient than // querying the files. if (num_levels_ > 1 || curr_file_level_->num_files > 3) { // Check if key is within a file's range. If search left bound and // right bound point to the same find, we are sure key falls in // range. assert(curr_level_ == 0 || curr_index_in_curr_level_ == start_index_in_curr_level_ || user_comparator_->CompareWithoutTimestamp( user_key_, ExtractUserKey(f->smallest_key)) <= 0); int cmp_smallest = user_comparator_->CompareWithoutTimestamp( user_key_, ExtractUserKey(f->smallest_key)); if (cmp_smallest >= 0) { cmp_largest = user_comparator_->CompareWithoutTimestamp( user_key_, ExtractUserKey(f->largest_key)); } // Setup file search bound for the next level based on the // comparison results if (curr_level_ > 0) { file_indexer_->GetNextLevelIndex(curr_level_, curr_index_in_curr_level_, cmp_smallest, cmp_largest, &search_left_bound_, &search_right_bound_); } // Key falls out of current file's range if (cmp_smallest < 0 || cmp_largest > 0) { if (curr_level_ == 0) { ++curr_index_in_curr_level_; continue; } else { // Search next level. break; } } } #ifndef NDEBUG // Sanity check to make sure that the files are correctly sorted if (prev_file_) { if (curr_level_ != 0) { int comp_sign = internal_comparator_->Compare( prev_file_->largest_key, f->smallest_key); assert(comp_sign < 0); } else { // level == 0, the current file cannot be newer than the previous // one. Use compressed data structure, has no attribute seqNo assert(curr_index_in_curr_level_ > 0); assert(!NewestFirstBySeqNo(files_[0][curr_index_in_curr_level_], files_[0][curr_index_in_curr_level_-1])); } } prev_file_ = f; #endif returned_file_level_ = curr_level_; if (curr_level_ > 0 && cmp_largest < 0) { // No more files to search in this level. search_ended_ = !PrepareNextLevel(); } else { ++curr_index_in_curr_level_; } return f; } // Start searching next level. search_ended_ = !PrepareNextLevel(); } // Search ended. return nullptr; } // getter for current file level // for GET_HIT_L0, GET_HIT_L1 & GET_HIT_L2_AND_UP counts unsigned int GetHitFileLevel() { return hit_file_level_; } // Returns true if the most recent "hit file" (i.e., one returned by // GetNextFile()) is at the last index in its level. bool IsHitFileLastInLevel() { return is_hit_file_last_in_level_; } private: unsigned int num_levels_; unsigned int curr_level_; unsigned int returned_file_level_; unsigned int hit_file_level_; int32_t search_left_bound_; int32_t search_right_bound_; #ifndef NDEBUG std::vector* files_; #endif autovector* level_files_brief_; bool search_ended_; bool is_hit_file_last_in_level_; LevelFilesBrief* curr_file_level_; unsigned int curr_index_in_curr_level_; unsigned int start_index_in_curr_level_; Slice user_key_; Slice ikey_; FileIndexer* file_indexer_; const Comparator* user_comparator_; const InternalKeyComparator* internal_comparator_; #ifndef NDEBUG FdWithKeyRange* prev_file_; #endif // Setup local variables to search next level. // Returns false if there are no more levels to search. bool PrepareNextLevel() { curr_level_++; while (curr_level_ < num_levels_) { curr_file_level_ = &(*level_files_brief_)[curr_level_]; if (curr_file_level_->num_files == 0) { // When current level is empty, the search bound generated from upper // level must be [0, -1] or [0, FileIndexer::kLevelMaxIndex] if it is // also empty. assert(search_left_bound_ == 0); assert(search_right_bound_ == -1 || search_right_bound_ == FileIndexer::kLevelMaxIndex); // Since current level is empty, it will need to search all files in // the next level search_left_bound_ = 0; search_right_bound_ = FileIndexer::kLevelMaxIndex; curr_level_++; continue; } // Some files may overlap each other. We find // all files that overlap user_key and process them in order from // newest to oldest. In the context of merge-operator, this can occur at // any level. Otherwise, it only occurs at Level-0 (since Put/Deletes // are always compacted into a single entry). int32_t start_index; if (curr_level_ == 0) { // On Level-0, we read through all files to check for overlap. start_index = 0; } else { // On Level-n (n>=1), files are sorted. Binary search to find the // earliest file whose largest key >= ikey. Search left bound and // right bound are used to narrow the range. if (search_left_bound_ <= search_right_bound_) { if (search_right_bound_ == FileIndexer::kLevelMaxIndex) { search_right_bound_ = static_cast(curr_file_level_->num_files) - 1; } // `search_right_bound_` is an inclusive upper-bound, but since it was // determined based on user key, it is still possible the lookup key // falls to the right of `search_right_bound_`'s corresponding file. // So, pass a limit one higher, which allows us to detect this case. start_index = FindFileInRange(*internal_comparator_, *curr_file_level_, ikey_, static_cast(search_left_bound_), static_cast(search_right_bound_) + 1); if (start_index == search_right_bound_ + 1) { // `ikey_` comes after `search_right_bound_`. The lookup key does // not exist on this level, so let's skip this level and do a full // binary search on the next level. search_left_bound_ = 0; search_right_bound_ = FileIndexer::kLevelMaxIndex; curr_level_++; continue; } } else { // search_left_bound > search_right_bound, key does not exist in // this level. Since no comparison is done in this level, it will // need to search all files in the next level. search_left_bound_ = 0; search_right_bound_ = FileIndexer::kLevelMaxIndex; curr_level_++; continue; } } start_index_in_curr_level_ = start_index; curr_index_in_curr_level_ = start_index; #ifndef NDEBUG prev_file_ = nullptr; #endif return true; } // curr_level_ = num_levels_. So, no more levels to search. return false; } }; class FilePickerMultiGet { private: struct FilePickerContext; public: FilePickerMultiGet(MultiGetRange* range, autovector* file_levels, unsigned int num_levels, FileIndexer* file_indexer, const Comparator* user_comparator, const InternalKeyComparator* internal_comparator) : num_levels_(num_levels), curr_level_(static_cast(-1)), returned_file_level_(static_cast(-1)), hit_file_level_(static_cast(-1)), range_(range), batch_iter_(range->begin()), batch_iter_prev_(range->begin()), upper_key_(range->begin()), maybe_repeat_key_(false), current_level_range_(*range, range->begin(), range->end()), current_file_range_(*range, range->begin(), range->end()), level_files_brief_(file_levels), is_hit_file_last_in_level_(false), curr_file_level_(nullptr), file_indexer_(file_indexer), user_comparator_(user_comparator), internal_comparator_(internal_comparator) { for (auto iter = range_->begin(); iter != range_->end(); ++iter) { fp_ctx_array_[iter.index()] = FilePickerContext(0, FileIndexer::kLevelMaxIndex); } // Setup member variables to search first level. search_ended_ = !PrepareNextLevel(); if (!search_ended_) { // REVISIT // Prefetch Level 0 table data to avoid cache miss if possible. // As of now, only PlainTableReader and CuckooTableReader do any // prefetching. This may not be necessary anymore once we implement // batching in those table readers for (unsigned int i = 0; i < (*level_files_brief_)[0].num_files; ++i) { auto* r = (*level_files_brief_)[0].files[i].fd.table_reader; if (r) { for (auto iter = range_->begin(); iter != range_->end(); ++iter) { r->Prepare(iter->ikey); } } } } } int GetCurrentLevel() const { return curr_level_; } // Iterates through files in the current level until it finds a file that // contains atleast one key from the MultiGet batch bool GetNextFileInLevelWithKeys(MultiGetRange* next_file_range, size_t* file_index, FdWithKeyRange** fd, bool* is_last_key_in_file) { size_t curr_file_index = *file_index; FdWithKeyRange* f = nullptr; bool file_hit = false; int cmp_largest = -1; if (curr_file_index >= curr_file_level_->num_files) { // In the unlikely case the next key is a duplicate of the current key, // and the current key is the last in the level and the internal key // was not found, we need to skip lookup for the remaining keys and // reset the search bounds if (batch_iter_ != current_level_range_.end()) { ++batch_iter_; for (; batch_iter_ != current_level_range_.end(); ++batch_iter_) { struct FilePickerContext& fp_ctx = fp_ctx_array_[batch_iter_.index()]; fp_ctx.search_left_bound = 0; fp_ctx.search_right_bound = FileIndexer::kLevelMaxIndex; } } return false; } // Loops over keys in the MultiGet batch until it finds a file with // atleast one of the keys. Then it keeps moving forward until the // last key in the batch that falls in that file while (batch_iter_ != current_level_range_.end() && (fp_ctx_array_[batch_iter_.index()].curr_index_in_curr_level == curr_file_index || !file_hit)) { struct FilePickerContext& fp_ctx = fp_ctx_array_[batch_iter_.index()]; f = &curr_file_level_->files[fp_ctx.curr_index_in_curr_level]; Slice& user_key = batch_iter_->ukey_without_ts; // Do key range filtering of files or/and fractional cascading if: // (1) not all the files are in level 0, or // (2) there are more than 3 current level files // If there are only 3 or less current level files in the system, we // skip the key range filtering. In this case, more likely, the system // is highly tuned to minimize number of tables queried by each query, // so it is unlikely that key range filtering is more efficient than // querying the files. if (num_levels_ > 1 || curr_file_level_->num_files > 3) { // Check if key is within a file's range. If search left bound and // right bound point to the same find, we are sure key falls in // range. int cmp_smallest = user_comparator_->CompareWithoutTimestamp( user_key, false, ExtractUserKey(f->smallest_key), true); assert(curr_level_ == 0 || fp_ctx.curr_index_in_curr_level == fp_ctx.start_index_in_curr_level || cmp_smallest <= 0); if (cmp_smallest >= 0) { cmp_largest = user_comparator_->CompareWithoutTimestamp( user_key, false, ExtractUserKey(f->largest_key), true); } else { cmp_largest = -1; } // Setup file search bound for the next level based on the // comparison results if (curr_level_ > 0) { file_indexer_->GetNextLevelIndex( curr_level_, fp_ctx.curr_index_in_curr_level, cmp_smallest, cmp_largest, &fp_ctx.search_left_bound, &fp_ctx.search_right_bound); } // Key falls out of current file's range if (cmp_smallest < 0 || cmp_largest > 0) { next_file_range->SkipKey(batch_iter_); } else { file_hit = true; } } else { file_hit = true; } if (cmp_largest == 0) { // cmp_largest is 0, which means the next key will not be in this // file, so stop looking further. However, its possible there are // duplicates in the batch, so find the upper bound for the batch // in this file (upper_key_) by skipping past the duplicates. We // leave batch_iter_ as is since we may have to pick up from there // for the next file, if this file has a merge value rather than // final value upper_key_ = batch_iter_; ++upper_key_; while (upper_key_ != current_level_range_.end() && user_comparator_->CompareWithoutTimestamp( batch_iter_->ukey_without_ts, false, upper_key_->ukey_without_ts, false) == 0) { ++upper_key_; } break; } else { if (curr_level_ == 0) { // We need to look through all files in level 0 ++fp_ctx.curr_index_in_curr_level; } ++batch_iter_; } if (!file_hit) { curr_file_index = (batch_iter_ != current_level_range_.end()) ? fp_ctx_array_[batch_iter_.index()].curr_index_in_curr_level : curr_file_level_->num_files; } } *fd = f; *file_index = curr_file_index; *is_last_key_in_file = cmp_largest == 0; if (!*is_last_key_in_file) { // If the largest key in the batch overlapping the file is not the // largest key in the file, upper_ley_ would not have been updated so // update it here upper_key_ = batch_iter_; } return file_hit; } FdWithKeyRange* GetNextFile() { while (!search_ended_) { // Start searching next level. if (batch_iter_ == current_level_range_.end()) { search_ended_ = !PrepareNextLevel(); continue; } else { if (maybe_repeat_key_) { maybe_repeat_key_ = false; // Check if we found the final value for the last key in the // previous lookup range. If we did, then there's no need to look // any further for that key, so advance batch_iter_. Else, keep // batch_iter_ positioned on that key so we look it up again in // the next file // For L0, always advance the key because we will look in the next // file regardless for all keys not found yet if (current_level_range_.CheckKeyDone(batch_iter_) || curr_level_ == 0) { batch_iter_ = upper_key_; } } // batch_iter_prev_ will become the start key for the next file // lookup batch_iter_prev_ = batch_iter_; } MultiGetRange next_file_range(current_level_range_, batch_iter_prev_, current_level_range_.end()); size_t curr_file_index = (batch_iter_ != current_level_range_.end()) ? fp_ctx_array_[batch_iter_.index()].curr_index_in_curr_level : curr_file_level_->num_files; FdWithKeyRange* f; bool is_last_key_in_file; if (!GetNextFileInLevelWithKeys(&next_file_range, &curr_file_index, &f, &is_last_key_in_file)) { search_ended_ = !PrepareNextLevel(); } else { if (is_last_key_in_file) { // Since cmp_largest is 0, batch_iter_ still points to the last key // that falls in this file, instead of the next one. Increment // the file index for all keys between batch_iter_ and upper_key_ auto tmp_iter = batch_iter_; while (tmp_iter != upper_key_) { ++(fp_ctx_array_[tmp_iter.index()].curr_index_in_curr_level); ++tmp_iter; } maybe_repeat_key_ = true; } // Set the range for this file current_file_range_ = MultiGetRange(next_file_range, batch_iter_prev_, upper_key_); returned_file_level_ = curr_level_; hit_file_level_ = curr_level_; is_hit_file_last_in_level_ = curr_file_index == curr_file_level_->num_files - 1; return f; } } // Search ended return nullptr; } // getter for current file level // for GET_HIT_L0, GET_HIT_L1 & GET_HIT_L2_AND_UP counts unsigned int GetHitFileLevel() { return hit_file_level_; } // Returns true if the most recent "hit file" (i.e., one returned by // GetNextFile()) is at the last index in its level. bool IsHitFileLastInLevel() { return is_hit_file_last_in_level_; } const MultiGetRange& CurrentFileRange() { return current_file_range_; } private: unsigned int num_levels_; unsigned int curr_level_; unsigned int returned_file_level_; unsigned int hit_file_level_; struct FilePickerContext { int32_t search_left_bound; int32_t search_right_bound; unsigned int curr_index_in_curr_level; unsigned int start_index_in_curr_level; FilePickerContext(int32_t left, int32_t right) : search_left_bound(left), search_right_bound(right), curr_index_in_curr_level(0), start_index_in_curr_level(0) {} FilePickerContext() = default; }; std::array fp_ctx_array_; MultiGetRange* range_; // Iterator to iterate through the keys in a MultiGet batch, that gets reset // at the beginning of each level. Each call to GetNextFile() will position // batch_iter_ at or right after the last key that was found in the returned // SST file MultiGetRange::Iterator batch_iter_; // An iterator that records the previous position of batch_iter_, i.e last // key found in the previous SST file, in order to serve as the start of // the batch key range for the next SST file MultiGetRange::Iterator batch_iter_prev_; MultiGetRange::Iterator upper_key_; bool maybe_repeat_key_; MultiGetRange current_level_range_; MultiGetRange current_file_range_; autovector* level_files_brief_; bool search_ended_; bool is_hit_file_last_in_level_; LevelFilesBrief* curr_file_level_; FileIndexer* file_indexer_; const Comparator* user_comparator_; const InternalKeyComparator* internal_comparator_; // Setup local variables to search next level. // Returns false if there are no more levels to search. bool PrepareNextLevel() { if (curr_level_ == 0) { MultiGetRange::Iterator mget_iter = current_level_range_.begin(); if (fp_ctx_array_[mget_iter.index()].curr_index_in_curr_level < curr_file_level_->num_files) { batch_iter_prev_ = current_level_range_.begin(); upper_key_ = batch_iter_ = current_level_range_.begin(); return true; } } curr_level_++; // Reset key range to saved value while (curr_level_ < num_levels_) { bool level_contains_keys = false; curr_file_level_ = &(*level_files_brief_)[curr_level_]; if (curr_file_level_->num_files == 0) { // When current level is empty, the search bound generated from upper // level must be [0, -1] or [0, FileIndexer::kLevelMaxIndex] if it is // also empty. for (auto mget_iter = current_level_range_.begin(); mget_iter != current_level_range_.end(); ++mget_iter) { struct FilePickerContext& fp_ctx = fp_ctx_array_[mget_iter.index()]; assert(fp_ctx.search_left_bound == 0); assert(fp_ctx.search_right_bound == -1 || fp_ctx.search_right_bound == FileIndexer::kLevelMaxIndex); // Since current level is empty, it will need to search all files in // the next level fp_ctx.search_left_bound = 0; fp_ctx.search_right_bound = FileIndexer::kLevelMaxIndex; } // Skip all subsequent empty levels do { ++curr_level_; } while ((curr_level_ < num_levels_) && (*level_files_brief_)[curr_level_].num_files == 0); continue; } // Some files may overlap each other. We find // all files that overlap user_key and process them in order from // newest to oldest. In the context of merge-operator, this can occur at // any level. Otherwise, it only occurs at Level-0 (since Put/Deletes // are always compacted into a single entry). int32_t start_index = -1; current_level_range_ = MultiGetRange(*range_, range_->begin(), range_->end()); for (auto mget_iter = current_level_range_.begin(); mget_iter != current_level_range_.end(); ++mget_iter) { struct FilePickerContext& fp_ctx = fp_ctx_array_[mget_iter.index()]; if (curr_level_ == 0) { // On Level-0, we read through all files to check for overlap. start_index = 0; level_contains_keys = true; } else { // On Level-n (n>=1), files are sorted. Binary search to find the // earliest file whose largest key >= ikey. Search left bound and // right bound are used to narrow the range. if (fp_ctx.search_left_bound <= fp_ctx.search_right_bound) { if (fp_ctx.search_right_bound == FileIndexer::kLevelMaxIndex) { fp_ctx.search_right_bound = static_cast(curr_file_level_->num_files) - 1; } // `search_right_bound_` is an inclusive upper-bound, but since it // was determined based on user key, it is still possible the lookup // key falls to the right of `search_right_bound_`'s corresponding // file. So, pass a limit one higher, which allows us to detect this // case. Slice& ikey = mget_iter->ikey; start_index = FindFileInRange( *internal_comparator_, *curr_file_level_, ikey, static_cast(fp_ctx.search_left_bound), static_cast(fp_ctx.search_right_bound) + 1); if (start_index == fp_ctx.search_right_bound + 1) { // `ikey_` comes after `search_right_bound_`. The lookup key does // not exist on this level, so let's skip this level and do a full // binary search on the next level. fp_ctx.search_left_bound = 0; fp_ctx.search_right_bound = FileIndexer::kLevelMaxIndex; current_level_range_.SkipKey(mget_iter); continue; } else { level_contains_keys = true; } } else { // search_left_bound > search_right_bound, key does not exist in // this level. Since no comparison is done in this level, it will // need to search all files in the next level. fp_ctx.search_left_bound = 0; fp_ctx.search_right_bound = FileIndexer::kLevelMaxIndex; current_level_range_.SkipKey(mget_iter); continue; } } fp_ctx.start_index_in_curr_level = start_index; fp_ctx.curr_index_in_curr_level = start_index; } if (level_contains_keys) { batch_iter_prev_ = current_level_range_.begin(); upper_key_ = batch_iter_ = current_level_range_.begin(); return true; } curr_level_++; } // curr_level_ = num_levels_. So, no more levels to search. return false; } }; } // anonymous namespace VersionStorageInfo::~VersionStorageInfo() { delete[] files_; } Version::~Version() { assert(refs_ == 0); // Remove from linked list prev_->next_ = next_; next_->prev_ = prev_; // Drop references to files for (int level = 0; level < storage_info_.num_levels_; level++) { for (size_t i = 0; i < storage_info_.files_[level].size(); i++) { FileMetaData* f = storage_info_.files_[level][i]; assert(f->refs > 0); f->refs--; if (f->refs <= 0) { assert(cfd_ != nullptr); uint32_t path_id = f->fd.GetPathId(); assert(path_id < cfd_->ioptions()->cf_paths.size()); vset_->obsolete_files_.push_back( ObsoleteFileInfo(f, cfd_->ioptions()->cf_paths[path_id].path)); } } } } int FindFile(const InternalKeyComparator& icmp, const LevelFilesBrief& file_level, const Slice& key) { return FindFileInRange(icmp, file_level, key, 0, static_cast(file_level.num_files)); } void DoGenerateLevelFilesBrief(LevelFilesBrief* file_level, const std::vector& files, Arena* arena) { assert(file_level); assert(arena); size_t num = files.size(); file_level->num_files = num; char* mem = arena->AllocateAligned(num * sizeof(FdWithKeyRange)); file_level->files = new (mem)FdWithKeyRange[num]; for (size_t i = 0; i < num; i++) { Slice smallest_key = files[i]->smallest.Encode(); Slice largest_key = files[i]->largest.Encode(); // Copy key slice to sequential memory size_t smallest_size = smallest_key.size(); size_t largest_size = largest_key.size(); mem = arena->AllocateAligned(smallest_size + largest_size); memcpy(mem, smallest_key.data(), smallest_size); memcpy(mem + smallest_size, largest_key.data(), largest_size); FdWithKeyRange& f = file_level->files[i]; f.fd = files[i]->fd; f.file_metadata = files[i]; f.smallest_key = Slice(mem, smallest_size); f.largest_key = Slice(mem + smallest_size, largest_size); } } static bool AfterFile(const Comparator* ucmp, const Slice* user_key, const FdWithKeyRange* f) { // nullptr user_key occurs before all keys and is therefore never after *f return (user_key != nullptr && ucmp->CompareWithoutTimestamp(*user_key, ExtractUserKey(f->largest_key)) > 0); } static bool BeforeFile(const Comparator* ucmp, const Slice* user_key, const FdWithKeyRange* f) { // nullptr user_key occurs after all keys and is therefore never before *f return (user_key != nullptr && ucmp->CompareWithoutTimestamp(*user_key, ExtractUserKey(f->smallest_key)) < 0); } bool SomeFileOverlapsRange( const InternalKeyComparator& icmp, bool disjoint_sorted_files, const LevelFilesBrief& file_level, const Slice* smallest_user_key, const Slice* largest_user_key) { const Comparator* ucmp = icmp.user_comparator(); if (!disjoint_sorted_files) { // Need to check against all files for (size_t i = 0; i < file_level.num_files; i++) { const FdWithKeyRange* f = &(file_level.files[i]); if (AfterFile(ucmp, smallest_user_key, f) || BeforeFile(ucmp, largest_user_key, f)) { // No overlap } else { return true; // Overlap } } return false; } // Binary search over file list uint32_t index = 0; if (smallest_user_key != nullptr) { // Find the leftmost possible internal key for smallest_user_key InternalKey small; small.SetMinPossibleForUserKey(*smallest_user_key); index = FindFile(icmp, file_level, small.Encode()); } if (index >= file_level.num_files) { // beginning of range is after all files, so no overlap. return false; } return !BeforeFile(ucmp, largest_user_key, &file_level.files[index]); } namespace { class LevelIterator final : public InternalIterator { public: // @param read_options Must outlive this iterator. LevelIterator(TableCache* table_cache, const ReadOptions& read_options, const FileOptions& file_options, const InternalKeyComparator& icomparator, const LevelFilesBrief* flevel, const SliceTransform* prefix_extractor, bool should_sample, HistogramImpl* file_read_hist, TableReaderCaller caller, bool skip_filters, int level, RangeDelAggregator* range_del_agg, const std::vector* compaction_boundaries = nullptr, bool allow_unprepared_value = false) : table_cache_(table_cache), read_options_(read_options), file_options_(file_options), icomparator_(icomparator), user_comparator_(icomparator.user_comparator()), flevel_(flevel), prefix_extractor_(prefix_extractor), file_read_hist_(file_read_hist), should_sample_(should_sample), caller_(caller), skip_filters_(skip_filters), allow_unprepared_value_(allow_unprepared_value), file_index_(flevel_->num_files), level_(level), range_del_agg_(range_del_agg), pinned_iters_mgr_(nullptr), compaction_boundaries_(compaction_boundaries) { // Empty level is not supported. assert(flevel_ != nullptr && flevel_->num_files > 0); } ~LevelIterator() override { delete file_iter_.Set(nullptr); } void Seek(const Slice& target) override; void SeekForPrev(const Slice& target) override; void SeekToFirst() override; void SeekToLast() override; void Next() final override; bool NextAndGetResult(IterateResult* result) override; void Prev() override; bool Valid() const override { return file_iter_.Valid(); } Slice key() const override { assert(Valid()); return file_iter_.key(); } Slice value() const override { assert(Valid()); return file_iter_.value(); } Status status() const override { return file_iter_.iter() ? file_iter_.status() : Status::OK(); } bool PrepareValue() override { return file_iter_.PrepareValue(); } inline bool MayBeOutOfLowerBound() override { assert(Valid()); return may_be_out_of_lower_bound_ && file_iter_.MayBeOutOfLowerBound(); } inline IterBoundCheck UpperBoundCheckResult() override { if (Valid()) { return file_iter_.UpperBoundCheckResult(); } else { return IterBoundCheck::kUnknown; } } void SetPinnedItersMgr(PinnedIteratorsManager* pinned_iters_mgr) override { pinned_iters_mgr_ = pinned_iters_mgr; if (file_iter_.iter()) { file_iter_.SetPinnedItersMgr(pinned_iters_mgr); } } bool IsKeyPinned() const override { return pinned_iters_mgr_ && pinned_iters_mgr_->PinningEnabled() && file_iter_.iter() && file_iter_.IsKeyPinned(); } bool IsValuePinned() const override { return pinned_iters_mgr_ && pinned_iters_mgr_->PinningEnabled() && file_iter_.iter() && file_iter_.IsValuePinned(); } private: // Return true if at least one invalid file is seen and skipped. bool SkipEmptyFileForward(); void SkipEmptyFileBackward(); void SetFileIterator(InternalIterator* iter); void InitFileIterator(size_t new_file_index); const Slice& file_smallest_key(size_t file_index) { assert(file_index < flevel_->num_files); return flevel_->files[file_index].smallest_key; } bool KeyReachedUpperBound(const Slice& internal_key) { return read_options_.iterate_upper_bound != nullptr && user_comparator_.CompareWithoutTimestamp( ExtractUserKey(internal_key), /*a_has_ts=*/true, *read_options_.iterate_upper_bound, /*b_has_ts=*/false) >= 0; } InternalIterator* NewFileIterator() { assert(file_index_ < flevel_->num_files); auto file_meta = flevel_->files[file_index_]; if (should_sample_) { sample_file_read_inc(file_meta.file_metadata); } const InternalKey* smallest_compaction_key = nullptr; const InternalKey* largest_compaction_key = nullptr; if (compaction_boundaries_ != nullptr) { smallest_compaction_key = (*compaction_boundaries_)[file_index_].smallest; largest_compaction_key = (*compaction_boundaries_)[file_index_].largest; } CheckMayBeOutOfLowerBound(); return table_cache_->NewIterator( read_options_, file_options_, icomparator_, *file_meta.file_metadata, range_del_agg_, prefix_extractor_, nullptr /* don't need reference to table */, file_read_hist_, caller_, /*arena=*/nullptr, skip_filters_, level_, /*max_file_size_for_l0_meta_pin=*/0, smallest_compaction_key, largest_compaction_key, allow_unprepared_value_); } // Check if current file being fully within iterate_lower_bound. // // Note MyRocks may update iterate bounds between seek. To workaround it, // we need to check and update may_be_out_of_lower_bound_ accordingly. void CheckMayBeOutOfLowerBound() { if (read_options_.iterate_lower_bound != nullptr && file_index_ < flevel_->num_files) { may_be_out_of_lower_bound_ = user_comparator_.CompareWithoutTimestamp( ExtractUserKey(file_smallest_key(file_index_)), /*a_has_ts=*/true, *read_options_.iterate_lower_bound, /*b_has_ts=*/false) < 0; } } TableCache* table_cache_; const ReadOptions& read_options_; const FileOptions& file_options_; const InternalKeyComparator& icomparator_; const UserComparatorWrapper user_comparator_; const LevelFilesBrief* flevel_; mutable FileDescriptor current_value_; // `prefix_extractor_` may be non-null even for total order seek. Checking // this variable is not the right way to identify whether prefix iterator // is used. const SliceTransform* prefix_extractor_; HistogramImpl* file_read_hist_; bool should_sample_; TableReaderCaller caller_; bool skip_filters_; bool allow_unprepared_value_; bool may_be_out_of_lower_bound_ = true; size_t file_index_; int level_; RangeDelAggregator* range_del_agg_; IteratorWrapper file_iter_; // May be nullptr PinnedIteratorsManager* pinned_iters_mgr_; // To be propagated to RangeDelAggregator in order to safely truncate range // tombstones. const std::vector* compaction_boundaries_; }; void LevelIterator::Seek(const Slice& target) { // Check whether the seek key fall under the same file bool need_to_reseek = true; if (file_iter_.iter() != nullptr && file_index_ < flevel_->num_files) { const FdWithKeyRange& cur_file = flevel_->files[file_index_]; if (icomparator_.InternalKeyComparator::Compare( target, cur_file.largest_key) <= 0 && icomparator_.InternalKeyComparator::Compare( target, cur_file.smallest_key) >= 0) { need_to_reseek = false; assert(static_cast(FindFile(icomparator_, *flevel_, target)) == file_index_); } } if (need_to_reseek) { TEST_SYNC_POINT("LevelIterator::Seek:BeforeFindFile"); size_t new_file_index = FindFile(icomparator_, *flevel_, target); InitFileIterator(new_file_index); } if (file_iter_.iter() != nullptr) { file_iter_.Seek(target); } if (SkipEmptyFileForward() && prefix_extractor_ != nullptr && !read_options_.total_order_seek && !read_options_.auto_prefix_mode && file_iter_.iter() != nullptr && file_iter_.Valid()) { // We've skipped the file we initially positioned to. In the prefix // seek case, it is likely that the file is skipped because of // prefix bloom or hash, where more keys are skipped. We then check // the current key and invalidate the iterator if the prefix is // already passed. // When doing prefix iterator seek, when keys for one prefix have // been exhausted, it can jump to any key that is larger. Here we are // enforcing a stricter contract than that, in order to make it easier for // higher layers (merging and DB iterator) to reason the correctness: // 1. Within the prefix, the result should be accurate. // 2. If keys for the prefix is exhausted, it is either positioned to the // next key after the prefix, or make the iterator invalid. // A side benefit will be that it invalidates the iterator earlier so that // the upper level merging iterator can merge fewer child iterators. size_t ts_sz = user_comparator_.timestamp_size(); Slice target_user_key_without_ts = ExtractUserKeyAndStripTimestamp(target, ts_sz); Slice file_user_key_without_ts = ExtractUserKeyAndStripTimestamp(file_iter_.key(), ts_sz); if (prefix_extractor_->InDomain(target_user_key_without_ts) && (!prefix_extractor_->InDomain(file_user_key_without_ts) || user_comparator_.CompareWithoutTimestamp( prefix_extractor_->Transform(target_user_key_without_ts), false, prefix_extractor_->Transform(file_user_key_without_ts), false) != 0)) { SetFileIterator(nullptr); } } CheckMayBeOutOfLowerBound(); } void LevelIterator::SeekForPrev(const Slice& target) { size_t new_file_index = FindFile(icomparator_, *flevel_, target); if (new_file_index >= flevel_->num_files) { new_file_index = flevel_->num_files - 1; } InitFileIterator(new_file_index); if (file_iter_.iter() != nullptr) { file_iter_.SeekForPrev(target); SkipEmptyFileBackward(); } CheckMayBeOutOfLowerBound(); } void LevelIterator::SeekToFirst() { InitFileIterator(0); if (file_iter_.iter() != nullptr) { file_iter_.SeekToFirst(); } SkipEmptyFileForward(); CheckMayBeOutOfLowerBound(); } void LevelIterator::SeekToLast() { InitFileIterator(flevel_->num_files - 1); if (file_iter_.iter() != nullptr) { file_iter_.SeekToLast(); } SkipEmptyFileBackward(); CheckMayBeOutOfLowerBound(); } void LevelIterator::Next() { assert(Valid()); file_iter_.Next(); SkipEmptyFileForward(); } bool LevelIterator::NextAndGetResult(IterateResult* result) { assert(Valid()); bool is_valid = file_iter_.NextAndGetResult(result); if (!is_valid) { SkipEmptyFileForward(); is_valid = Valid(); if (is_valid) { result->key = key(); result->bound_check_result = file_iter_.UpperBoundCheckResult(); // Ideally, we should return the real file_iter_.value_prepared but the // information is not here. It would casue an extra PrepareValue() // for the first key of a file. result->value_prepared = !allow_unprepared_value_; } } return is_valid; } void LevelIterator::Prev() { assert(Valid()); file_iter_.Prev(); SkipEmptyFileBackward(); } bool LevelIterator::SkipEmptyFileForward() { bool seen_empty_file = false; while (file_iter_.iter() == nullptr || (!file_iter_.Valid() && file_iter_.status().ok() && file_iter_.iter()->UpperBoundCheckResult() != IterBoundCheck::kOutOfBound)) { seen_empty_file = true; // Move to next file if (file_index_ >= flevel_->num_files - 1) { // Already at the last file SetFileIterator(nullptr); break; } if (KeyReachedUpperBound(file_smallest_key(file_index_ + 1))) { SetFileIterator(nullptr); break; } InitFileIterator(file_index_ + 1); if (file_iter_.iter() != nullptr) { file_iter_.SeekToFirst(); } } return seen_empty_file; } void LevelIterator::SkipEmptyFileBackward() { while (file_iter_.iter() == nullptr || (!file_iter_.Valid() && file_iter_.status().ok())) { // Move to previous file if (file_index_ == 0) { // Already the first file SetFileIterator(nullptr); return; } InitFileIterator(file_index_ - 1); if (file_iter_.iter() != nullptr) { file_iter_.SeekToLast(); } } } void LevelIterator::SetFileIterator(InternalIterator* iter) { if (pinned_iters_mgr_ && iter) { iter->SetPinnedItersMgr(pinned_iters_mgr_); } InternalIterator* old_iter = file_iter_.Set(iter); if (pinned_iters_mgr_ && pinned_iters_mgr_->PinningEnabled()) { pinned_iters_mgr_->PinIterator(old_iter); } else { delete old_iter; } } void LevelIterator::InitFileIterator(size_t new_file_index) { if (new_file_index >= flevel_->num_files) { file_index_ = new_file_index; SetFileIterator(nullptr); return; } else { // If the file iterator shows incomplete, we try it again if users seek // to the same file, as this time we may go to a different data block // which is cached in block cache. // if (file_iter_.iter() != nullptr && !file_iter_.status().IsIncomplete() && new_file_index == file_index_) { // file_iter_ is already constructed with this iterator, so // no need to change anything } else { file_index_ = new_file_index; InternalIterator* iter = NewFileIterator(); SetFileIterator(iter); } } } } // anonymous namespace Status Version::GetTableProperties(std::shared_ptr* tp, const FileMetaData* file_meta, const std::string* fname) const { auto table_cache = cfd_->table_cache(); auto ioptions = cfd_->ioptions(); Status s = table_cache->GetTableProperties( file_options_, cfd_->internal_comparator(), file_meta->fd, tp, mutable_cf_options_.prefix_extractor.get(), true /* no io */); if (s.ok()) { return s; } // We only ignore error type `Incomplete` since it's by design that we // disallow table when it's not in table cache. if (!s.IsIncomplete()) { return s; } // 2. Table is not present in table cache, we'll read the table properties // directly from the properties block in the file. std::unique_ptr file; std::string file_name; if (fname != nullptr) { file_name = *fname; } else { file_name = TableFileName(ioptions->cf_paths, file_meta->fd.GetNumber(), file_meta->fd.GetPathId()); } s = ioptions->fs->NewRandomAccessFile(file_name, file_options_, &file, nullptr); if (!s.ok()) { return s; } TableProperties* raw_table_properties; // By setting the magic number to kInvalidTableMagicNumber, we can by // pass the magic number check in the footer. std::unique_ptr file_reader( new RandomAccessFileReader( std::move(file), file_name, nullptr /* env */, io_tracer_, nullptr /* stats */, 0 /* hist_type */, nullptr /* file_read_hist */, nullptr /* rate_limiter */, ioptions->listeners)); s = ReadTableProperties( file_reader.get(), file_meta->fd.GetFileSize(), Footer::kInvalidTableMagicNumber /* table's magic number */, *ioptions, &raw_table_properties, false /* compression_type_missing */); if (!s.ok()) { return s; } RecordTick(ioptions->statistics, NUMBER_DIRECT_LOAD_TABLE_PROPERTIES); *tp = std::shared_ptr(raw_table_properties); return s; } Status Version::GetPropertiesOfAllTables(TablePropertiesCollection* props) { Status s; for (int level = 0; level < storage_info_.num_levels_; level++) { s = GetPropertiesOfAllTables(props, level); if (!s.ok()) { return s; } } return Status::OK(); } Status Version::TablesRangeTombstoneSummary(int max_entries_to_print, std::string* out_str) { if (max_entries_to_print <= 0) { return Status::OK(); } int num_entries_left = max_entries_to_print; std::stringstream ss; for (int level = 0; level < storage_info_.num_levels_; level++) { for (const auto& file_meta : storage_info_.files_[level]) { auto fname = TableFileName(cfd_->ioptions()->cf_paths, file_meta->fd.GetNumber(), file_meta->fd.GetPathId()); ss << "=== file : " << fname << " ===\n"; TableCache* table_cache = cfd_->table_cache(); std::unique_ptr tombstone_iter; Status s = table_cache->GetRangeTombstoneIterator( ReadOptions(), cfd_->internal_comparator(), *file_meta, &tombstone_iter); if (!s.ok()) { return s; } if (tombstone_iter) { tombstone_iter->SeekToFirst(); while (tombstone_iter->Valid() && num_entries_left > 0) { ss << "start: " << tombstone_iter->start_key().ToString(true) << " end: " << tombstone_iter->end_key().ToString(true) << " seq: " << tombstone_iter->seq() << '\n'; tombstone_iter->Next(); num_entries_left--; } if (num_entries_left <= 0) { break; } } } if (num_entries_left <= 0) { break; } } assert(num_entries_left >= 0); if (num_entries_left <= 0) { ss << "(results may not be complete)\n"; } *out_str = ss.str(); return Status::OK(); } Status Version::GetPropertiesOfAllTables(TablePropertiesCollection* props, int level) { for (const auto& file_meta : storage_info_.files_[level]) { auto fname = TableFileName(cfd_->ioptions()->cf_paths, file_meta->fd.GetNumber(), file_meta->fd.GetPathId()); // 1. If the table is already present in table cache, load table // properties from there. std::shared_ptr table_properties; Status s = GetTableProperties(&table_properties, file_meta, &fname); if (s.ok()) { props->insert({fname, table_properties}); } else { return s; } } return Status::OK(); } Status Version::GetPropertiesOfTablesInRange( const Range* range, std::size_t n, TablePropertiesCollection* props) const { for (int level = 0; level < storage_info_.num_non_empty_levels(); level++) { for (decltype(n) i = 0; i < n; i++) { // Convert user_key into a corresponding internal key. InternalKey k1(range[i].start, kMaxSequenceNumber, kValueTypeForSeek); InternalKey k2(range[i].limit, kMaxSequenceNumber, kValueTypeForSeek); std::vector files; storage_info_.GetOverlappingInputs(level, &k1, &k2, &files, -1, nullptr, false); for (const auto& file_meta : files) { auto fname = TableFileName(cfd_->ioptions()->cf_paths, file_meta->fd.GetNumber(), file_meta->fd.GetPathId()); if (props->count(fname) == 0) { // 1. If the table is already present in table cache, load table // properties from there. std::shared_ptr table_properties; Status s = GetTableProperties(&table_properties, file_meta, &fname); if (s.ok()) { props->insert({fname, table_properties}); } else { return s; } } } } } return Status::OK(); } Status Version::GetAggregatedTableProperties( std::shared_ptr* tp, int level) { TablePropertiesCollection props; Status s; if (level < 0) { s = GetPropertiesOfAllTables(&props); } else { s = GetPropertiesOfAllTables(&props, level); } if (!s.ok()) { return s; } auto* new_tp = new TableProperties(); for (const auto& item : props) { new_tp->Add(*item.second); } tp->reset(new_tp); return Status::OK(); } size_t Version::GetMemoryUsageByTableReaders() { size_t total_usage = 0; for (auto& file_level : storage_info_.level_files_brief_) { for (size_t i = 0; i < file_level.num_files; i++) { total_usage += cfd_->table_cache()->GetMemoryUsageByTableReader( file_options_, cfd_->internal_comparator(), file_level.files[i].fd, mutable_cf_options_.prefix_extractor.get()); } } return total_usage; } void Version::GetColumnFamilyMetaData(ColumnFamilyMetaData* cf_meta) { assert(cf_meta); assert(cfd_); cf_meta->name = cfd_->GetName(); cf_meta->size = 0; cf_meta->file_count = 0; cf_meta->levels.clear(); auto* ioptions = cfd_->ioptions(); auto* vstorage = storage_info(); for (int level = 0; level < cfd_->NumberLevels(); level++) { uint64_t level_size = 0; cf_meta->file_count += vstorage->LevelFiles(level).size(); std::vector files; for (const auto& file : vstorage->LevelFiles(level)) { uint32_t path_id = file->fd.GetPathId(); std::string file_path; if (path_id < ioptions->cf_paths.size()) { file_path = ioptions->cf_paths[path_id].path; } else { assert(!ioptions->cf_paths.empty()); file_path = ioptions->cf_paths.back().path; } const uint64_t file_number = file->fd.GetNumber(); files.emplace_back(SstFileMetaData{ MakeTableFileName("", file_number), file_number, file_path, static_cast(file->fd.GetFileSize()), file->fd.smallest_seqno, file->fd.largest_seqno, file->smallest.user_key().ToString(), file->largest.user_key().ToString(), file->stats.num_reads_sampled.load(std::memory_order_relaxed), file->being_compacted, file->oldest_blob_file_number, file->TryGetOldestAncesterTime(), file->TryGetFileCreationTime(), file->file_checksum, file->file_checksum_func_name}); files.back().num_entries = file->num_entries; files.back().num_deletions = file->num_deletions; level_size += file->fd.GetFileSize(); } cf_meta->levels.emplace_back( level, level_size, std::move(files)); cf_meta->size += level_size; } } uint64_t Version::GetSstFilesSize() { uint64_t sst_files_size = 0; for (int level = 0; level < storage_info_.num_levels_; level++) { for (const auto& file_meta : storage_info_.LevelFiles(level)) { sst_files_size += file_meta->fd.GetFileSize(); } } return sst_files_size; } void Version::GetCreationTimeOfOldestFile(uint64_t* creation_time) { uint64_t oldest_time = port::kMaxUint64; for (int level = 0; level < storage_info_.num_non_empty_levels_; level++) { for (FileMetaData* meta : storage_info_.LevelFiles(level)) { assert(meta->fd.table_reader != nullptr); uint64_t file_creation_time = meta->TryGetFileCreationTime(); if (file_creation_time == kUnknownFileCreationTime) { *creation_time = 0; return; } if (file_creation_time < oldest_time) { oldest_time = file_creation_time; } } } *creation_time = oldest_time; } uint64_t VersionStorageInfo::GetEstimatedActiveKeys() const { // Estimation will be inaccurate when: // (1) there exist merge keys // (2) keys are directly overwritten // (3) deletion on non-existing keys // (4) low number of samples if (current_num_samples_ == 0) { return 0; } if (current_num_non_deletions_ <= current_num_deletions_) { return 0; } uint64_t est = current_num_non_deletions_ - current_num_deletions_; uint64_t file_count = 0; for (int level = 0; level < num_levels_; ++level) { file_count += files_[level].size(); } if (current_num_samples_ < file_count) { // casting to avoid overflowing return static_cast( (est * static_cast(file_count) / current_num_samples_) ); } else { return est; } } double VersionStorageInfo::GetEstimatedCompressionRatioAtLevel( int level) const { assert(level < num_levels_); uint64_t sum_file_size_bytes = 0; uint64_t sum_data_size_bytes = 0; for (auto* file_meta : files_[level]) { sum_file_size_bytes += file_meta->fd.GetFileSize(); sum_data_size_bytes += file_meta->raw_key_size + file_meta->raw_value_size; } if (sum_file_size_bytes == 0) { return -1.0; } return static_cast(sum_data_size_bytes) / sum_file_size_bytes; } void Version::AddIterators(const ReadOptions& read_options, const FileOptions& soptions, MergeIteratorBuilder* merge_iter_builder, RangeDelAggregator* range_del_agg, bool allow_unprepared_value) { assert(storage_info_.finalized_); for (int level = 0; level < storage_info_.num_non_empty_levels(); level++) { AddIteratorsForLevel(read_options, soptions, merge_iter_builder, level, range_del_agg, allow_unprepared_value); } } void Version::AddIteratorsForLevel(const ReadOptions& read_options, const FileOptions& soptions, MergeIteratorBuilder* merge_iter_builder, int level, RangeDelAggregator* range_del_agg, bool allow_unprepared_value) { assert(storage_info_.finalized_); if (level >= storage_info_.num_non_empty_levels()) { // This is an empty level return; } else if (storage_info_.LevelFilesBrief(level).num_files == 0) { // No files in this level return; } bool should_sample = should_sample_file_read(); auto* arena = merge_iter_builder->GetArena(); if (level == 0) { // Merge all level zero files together since they may overlap for (size_t i = 0; i < storage_info_.LevelFilesBrief(0).num_files; i++) { const auto& file = storage_info_.LevelFilesBrief(0).files[i]; merge_iter_builder->AddIterator(cfd_->table_cache()->NewIterator( read_options, soptions, cfd_->internal_comparator(), *file.file_metadata, range_del_agg, mutable_cf_options_.prefix_extractor.get(), nullptr, cfd_->internal_stats()->GetFileReadHist(0), TableReaderCaller::kUserIterator, arena, /*skip_filters=*/false, /*level=*/0, max_file_size_for_l0_meta_pin_, /*smallest_compaction_key=*/nullptr, /*largest_compaction_key=*/nullptr, allow_unprepared_value)); } if (should_sample) { // Count ones for every L0 files. This is done per iterator creation // rather than Seek(), while files in other levels are recored per seek. // If users execute one range query per iterator, there may be some // discrepancy here. for (FileMetaData* meta : storage_info_.LevelFiles(0)) { sample_file_read_inc(meta); } } } else if (storage_info_.LevelFilesBrief(level).num_files > 0) { // For levels > 0, we can use a concatenating iterator that sequentially // walks through the non-overlapping files in the level, opening them // lazily. auto* mem = arena->AllocateAligned(sizeof(LevelIterator)); merge_iter_builder->AddIterator(new (mem) LevelIterator( cfd_->table_cache(), read_options, soptions, cfd_->internal_comparator(), &storage_info_.LevelFilesBrief(level), mutable_cf_options_.prefix_extractor.get(), should_sample_file_read(), cfd_->internal_stats()->GetFileReadHist(level), TableReaderCaller::kUserIterator, IsFilterSkipped(level), level, range_del_agg, /*compaction_boundaries=*/nullptr, allow_unprepared_value)); } } Status Version::OverlapWithLevelIterator(const ReadOptions& read_options, const FileOptions& file_options, const Slice& smallest_user_key, const Slice& largest_user_key, int level, bool* overlap) { assert(storage_info_.finalized_); auto icmp = cfd_->internal_comparator(); auto ucmp = icmp.user_comparator(); Arena arena; Status status; ReadRangeDelAggregator range_del_agg(&icmp, kMaxSequenceNumber /* upper_bound */); *overlap = false; if (level == 0) { for (size_t i = 0; i < storage_info_.LevelFilesBrief(0).num_files; i++) { const auto file = &storage_info_.LevelFilesBrief(0).files[i]; if (AfterFile(ucmp, &smallest_user_key, file) || BeforeFile(ucmp, &largest_user_key, file)) { continue; } ScopedArenaIterator iter(cfd_->table_cache()->NewIterator( read_options, file_options, cfd_->internal_comparator(), *file->file_metadata, &range_del_agg, mutable_cf_options_.prefix_extractor.get(), nullptr, cfd_->internal_stats()->GetFileReadHist(0), TableReaderCaller::kUserIterator, &arena, /*skip_filters=*/false, /*level=*/0, max_file_size_for_l0_meta_pin_, /*smallest_compaction_key=*/nullptr, /*largest_compaction_key=*/nullptr, /*allow_unprepared_value=*/false)); status = OverlapWithIterator( ucmp, smallest_user_key, largest_user_key, iter.get(), overlap); if (!status.ok() || *overlap) { break; } } } else if (storage_info_.LevelFilesBrief(level).num_files > 0) { auto mem = arena.AllocateAligned(sizeof(LevelIterator)); ScopedArenaIterator iter(new (mem) LevelIterator( cfd_->table_cache(), read_options, file_options, cfd_->internal_comparator(), &storage_info_.LevelFilesBrief(level), mutable_cf_options_.prefix_extractor.get(), should_sample_file_read(), cfd_->internal_stats()->GetFileReadHist(level), TableReaderCaller::kUserIterator, IsFilterSkipped(level), level, &range_del_agg)); status = OverlapWithIterator( ucmp, smallest_user_key, largest_user_key, iter.get(), overlap); } if (status.ok() && *overlap == false && range_del_agg.IsRangeOverlapped(smallest_user_key, largest_user_key)) { *overlap = true; } return status; } VersionStorageInfo::VersionStorageInfo( const InternalKeyComparator* internal_comparator, const Comparator* user_comparator, int levels, CompactionStyle compaction_style, VersionStorageInfo* ref_vstorage, bool _force_consistency_checks) : internal_comparator_(internal_comparator), user_comparator_(user_comparator), // cfd is nullptr if Version is dummy num_levels_(levels), num_non_empty_levels_(0), file_indexer_(user_comparator), compaction_style_(compaction_style), files_(new std::vector[num_levels_]), base_level_(num_levels_ == 1 ? -1 : 1), level_multiplier_(0.0), files_by_compaction_pri_(num_levels_), level0_non_overlapping_(false), next_file_to_compact_by_size_(num_levels_), compaction_score_(num_levels_), compaction_level_(num_levels_), l0_delay_trigger_count_(0), accumulated_file_size_(0), accumulated_raw_key_size_(0), accumulated_raw_value_size_(0), accumulated_num_non_deletions_(0), accumulated_num_deletions_(0), current_num_non_deletions_(0), current_num_deletions_(0), current_num_samples_(0), estimated_compaction_needed_bytes_(0), finalized_(false), force_consistency_checks_(_force_consistency_checks) { if (ref_vstorage != nullptr) { accumulated_file_size_ = ref_vstorage->accumulated_file_size_; accumulated_raw_key_size_ = ref_vstorage->accumulated_raw_key_size_; accumulated_raw_value_size_ = ref_vstorage->accumulated_raw_value_size_; accumulated_num_non_deletions_ = ref_vstorage->accumulated_num_non_deletions_; accumulated_num_deletions_ = ref_vstorage->accumulated_num_deletions_; current_num_non_deletions_ = ref_vstorage->current_num_non_deletions_; current_num_deletions_ = ref_vstorage->current_num_deletions_; current_num_samples_ = ref_vstorage->current_num_samples_; oldest_snapshot_seqnum_ = ref_vstorage->oldest_snapshot_seqnum_; } } Version::Version(ColumnFamilyData* column_family_data, VersionSet* vset, const FileOptions& file_opt, const MutableCFOptions mutable_cf_options, const std::shared_ptr& io_tracer, uint64_t version_number) : env_(vset->env_), clock_(env_->GetSystemClock()), cfd_(column_family_data), info_log_((cfd_ == nullptr) ? nullptr : cfd_->ioptions()->info_log), db_statistics_((cfd_ == nullptr) ? nullptr : cfd_->ioptions()->statistics), table_cache_((cfd_ == nullptr) ? nullptr : cfd_->table_cache()), blob_file_cache_(cfd_ ? cfd_->blob_file_cache() : nullptr), merge_operator_((cfd_ == nullptr) ? nullptr : cfd_->ioptions()->merge_operator), storage_info_( (cfd_ == nullptr) ? nullptr : &cfd_->internal_comparator(), (cfd_ == nullptr) ? nullptr : cfd_->user_comparator(), cfd_ == nullptr ? 0 : cfd_->NumberLevels(), cfd_ == nullptr ? kCompactionStyleLevel : cfd_->ioptions()->compaction_style, (cfd_ == nullptr || cfd_->current() == nullptr) ? nullptr : cfd_->current()->storage_info(), cfd_ == nullptr ? false : cfd_->ioptions()->force_consistency_checks), vset_(vset), next_(this), prev_(this), refs_(0), file_options_(file_opt), mutable_cf_options_(mutable_cf_options), max_file_size_for_l0_meta_pin_( MaxFileSizeForL0MetaPin(mutable_cf_options_)), version_number_(version_number), io_tracer_(io_tracer) {} Status Version::GetBlob(const ReadOptions& read_options, const Slice& user_key, const Slice& blob_index_slice, PinnableSlice* value) const { if (read_options.read_tier == kBlockCacheTier) { return Status::Incomplete("Cannot read blob: no disk I/O allowed"); } BlobIndex blob_index; { Status s = blob_index.DecodeFrom(blob_index_slice); if (!s.ok()) { return s; } } return GetBlob(read_options, user_key, blob_index, value); } Status Version::GetBlob(const ReadOptions& read_options, const Slice& user_key, const BlobIndex& blob_index, PinnableSlice* value) const { assert(value); if (blob_index.HasTTL() || blob_index.IsInlined()) { return Status::Corruption("Unexpected TTL/inlined blob index"); } const auto& blob_files = storage_info_.GetBlobFiles(); const uint64_t blob_file_number = blob_index.file_number(); const auto it = blob_files.find(blob_file_number); if (it == blob_files.end()) { return Status::Corruption("Invalid blob file number"); } CacheHandleGuard blob_file_reader; { assert(blob_file_cache_); const Status s = blob_file_cache_->GetBlobFileReader(blob_file_number, &blob_file_reader); if (!s.ok()) { return s; } } assert(blob_file_reader.GetValue()); const Status s = blob_file_reader.GetValue()->GetBlob( read_options, user_key, blob_index.offset(), blob_index.size(), blob_index.compression(), value); return s; } void Version::Get(const ReadOptions& read_options, const LookupKey& k, PinnableSlice* value, std::string* timestamp, Status* status, MergeContext* merge_context, SequenceNumber* max_covering_tombstone_seq, bool* value_found, bool* key_exists, SequenceNumber* seq, ReadCallback* callback, bool* is_blob, bool do_merge) { Slice ikey = k.internal_key(); Slice user_key = k.user_key(); assert(status->ok() || status->IsMergeInProgress()); if (key_exists != nullptr) { // will falsify below if not found *key_exists = true; } PinnedIteratorsManager pinned_iters_mgr; uint64_t tracing_get_id = BlockCacheTraceHelper::kReservedGetId; if (vset_ && vset_->block_cache_tracer_ && vset_->block_cache_tracer_->is_tracing_enabled()) { tracing_get_id = vset_->block_cache_tracer_->NextGetId(); } // Note: the old StackableDB-based BlobDB passes in // GetImplOptions::is_blob_index; for the integrated BlobDB implementation, we // need to provide it here. bool is_blob_index = false; bool* const is_blob_to_use = is_blob ? is_blob : &is_blob_index; GetContext get_context( user_comparator(), merge_operator_, info_log_, db_statistics_, status->ok() ? GetContext::kNotFound : GetContext::kMerge, user_key, do_merge ? value : nullptr, do_merge ? timestamp : nullptr, value_found, merge_context, do_merge, max_covering_tombstone_seq, clock_, seq, merge_operator_ ? &pinned_iters_mgr : nullptr, callback, is_blob_to_use, tracing_get_id); // Pin blocks that we read to hold merge operands if (merge_operator_) { pinned_iters_mgr.StartPinning(); } FilePicker fp( storage_info_.files_, user_key, ikey, &storage_info_.level_files_brief_, storage_info_.num_non_empty_levels_, &storage_info_.file_indexer_, user_comparator(), internal_comparator()); FdWithKeyRange* f = fp.GetNextFile(); while (f != nullptr) { if (*max_covering_tombstone_seq > 0) { // The remaining files we look at will only contain covered keys, so we // stop here. break; } if (get_context.sample()) { sample_file_read_inc(f->file_metadata); } bool timer_enabled = GetPerfLevel() >= PerfLevel::kEnableTimeExceptForMutex && get_perf_context()->per_level_perf_context_enabled; StopWatchNano timer(clock_, timer_enabled /* auto_start */); *status = table_cache_->Get( read_options, *internal_comparator(), *f->file_metadata, ikey, &get_context, mutable_cf_options_.prefix_extractor.get(), cfd_->internal_stats()->GetFileReadHist(fp.GetHitFileLevel()), IsFilterSkipped(static_cast(fp.GetHitFileLevel()), fp.IsHitFileLastInLevel()), fp.GetHitFileLevel(), max_file_size_for_l0_meta_pin_); // TODO: examine the behavior for corrupted key if (timer_enabled) { PERF_COUNTER_BY_LEVEL_ADD(get_from_table_nanos, timer.ElapsedNanos(), fp.GetHitFileLevel()); } if (!status->ok()) { return; } // report the counters before returning if (get_context.State() != GetContext::kNotFound && get_context.State() != GetContext::kMerge && db_statistics_ != nullptr) { get_context.ReportCounters(); } switch (get_context.State()) { case GetContext::kNotFound: // Keep searching in other files break; case GetContext::kMerge: // TODO: update per-level perfcontext user_key_return_count for kMerge break; case GetContext::kFound: if (fp.GetHitFileLevel() == 0) { RecordTick(db_statistics_, GET_HIT_L0); } else if (fp.GetHitFileLevel() == 1) { RecordTick(db_statistics_, GET_HIT_L1); } else if (fp.GetHitFileLevel() >= 2) { RecordTick(db_statistics_, GET_HIT_L2_AND_UP); } PERF_COUNTER_BY_LEVEL_ADD(user_key_return_count, 1, fp.GetHitFileLevel()); if (is_blob_index) { if (do_merge && value) { *status = GetBlob(read_options, user_key, *value, value); if (!status->ok()) { if (status->IsIncomplete()) { get_context.MarkKeyMayExist(); } return; } } } return; case GetContext::kDeleted: // Use empty error message for speed *status = Status::NotFound(); return; case GetContext::kCorrupt: *status = Status::Corruption("corrupted key for ", user_key); return; case GetContext::kUnexpectedBlobIndex: ROCKS_LOG_ERROR(info_log_, "Encounter unexpected blob index."); *status = Status::NotSupported( "Encounter unexpected blob index. Please open DB with " "ROCKSDB_NAMESPACE::blob_db::BlobDB instead."); return; } f = fp.GetNextFile(); } if (db_statistics_ != nullptr) { get_context.ReportCounters(); } if (GetContext::kMerge == get_context.State()) { if (!do_merge) { *status = Status::OK(); return; } if (!merge_operator_) { *status = Status::InvalidArgument( "merge_operator is not properly initialized."); return; } // merge_operands are in saver and we hit the beginning of the key history // do a final merge of nullptr and operands; std::string* str_value = value != nullptr ? value->GetSelf() : nullptr; *status = MergeHelper::TimedFullMerge( merge_operator_, user_key, nullptr, merge_context->GetOperands(), str_value, info_log_, db_statistics_, clock_, nullptr /* result_operand */, true); if (LIKELY(value != nullptr)) { value->PinSelf(); } } else { if (key_exists != nullptr) { *key_exists = false; } *status = Status::NotFound(); // Use an empty error message for speed } } void Version::MultiGet(const ReadOptions& read_options, MultiGetRange* range, ReadCallback* callback) { PinnedIteratorsManager pinned_iters_mgr; // Pin blocks that we read to hold merge operands if (merge_operator_) { pinned_iters_mgr.StartPinning(); } uint64_t tracing_mget_id = BlockCacheTraceHelper::kReservedGetId; if (vset_ && vset_->block_cache_tracer_ && vset_->block_cache_tracer_->is_tracing_enabled()) { tracing_mget_id = vset_->block_cache_tracer_->NextGetId(); } // Even though we know the batch size won't be > MAX_BATCH_SIZE, // use autovector in order to avoid unnecessary construction of GetContext // objects, which is expensive autovector get_ctx; for (auto iter = range->begin(); iter != range->end(); ++iter) { assert(iter->s->ok() || iter->s->IsMergeInProgress()); get_ctx.emplace_back( user_comparator(), merge_operator_, info_log_, db_statistics_, iter->s->ok() ? GetContext::kNotFound : GetContext::kMerge, iter->ukey_with_ts, iter->value, iter->timestamp, nullptr, &(iter->merge_context), true, &iter->max_covering_tombstone_seq, clock_, nullptr, merge_operator_ ? &pinned_iters_mgr : nullptr, callback, &iter->is_blob_index, tracing_mget_id); // MergeInProgress status, if set, has been transferred to the get_context // state, so we set status to ok here. From now on, the iter status will // be used for IO errors, and get_context state will be used for any // key level errors *(iter->s) = Status::OK(); } int get_ctx_index = 0; for (auto iter = range->begin(); iter != range->end(); ++iter, get_ctx_index++) { iter->get_context = &(get_ctx[get_ctx_index]); } MultiGetRange file_picker_range(*range, range->begin(), range->end()); FilePickerMultiGet fp( &file_picker_range, &storage_info_.level_files_brief_, storage_info_.num_non_empty_levels_, &storage_info_.file_indexer_, user_comparator(), internal_comparator()); FdWithKeyRange* f = fp.GetNextFile(); Status s; uint64_t num_index_read = 0; uint64_t num_filter_read = 0; uint64_t num_data_read = 0; uint64_t num_sst_read = 0; while (f != nullptr) { MultiGetRange file_range = fp.CurrentFileRange(); bool timer_enabled = GetPerfLevel() >= PerfLevel::kEnableTimeExceptForMutex && get_perf_context()->per_level_perf_context_enabled; StopWatchNano timer(clock_, timer_enabled /* auto_start */); s = table_cache_->MultiGet( read_options, *internal_comparator(), *f->file_metadata, &file_range, mutable_cf_options_.prefix_extractor.get(), cfd_->internal_stats()->GetFileReadHist(fp.GetHitFileLevel()), IsFilterSkipped(static_cast(fp.GetHitFileLevel()), fp.IsHitFileLastInLevel()), fp.GetHitFileLevel()); // TODO: examine the behavior for corrupted key if (timer_enabled) { PERF_COUNTER_BY_LEVEL_ADD(get_from_table_nanos, timer.ElapsedNanos(), fp.GetHitFileLevel()); } if (!s.ok()) { // TODO: Set status for individual keys appropriately for (auto iter = file_range.begin(); iter != file_range.end(); ++iter) { *iter->s = s; file_range.MarkKeyDone(iter); } return; } uint64_t batch_size = 0; for (auto iter = file_range.begin(); s.ok() && iter != file_range.end(); ++iter) { GetContext& get_context = *iter->get_context; Status* status = iter->s; // The Status in the KeyContext takes precedence over GetContext state // Status may be an error if there were any IO errors in the table // reader. We never expect Status to be NotFound(), as that is // determined by get_context assert(!status->IsNotFound()); if (!status->ok()) { file_range.MarkKeyDone(iter); continue; } if (get_context.sample()) { sample_file_read_inc(f->file_metadata); } batch_size++; num_index_read += get_context.get_context_stats_.num_index_read; num_filter_read += get_context.get_context_stats_.num_filter_read; num_data_read += get_context.get_context_stats_.num_data_read; num_sst_read += get_context.get_context_stats_.num_sst_read; // report the counters before returning if (get_context.State() != GetContext::kNotFound && get_context.State() != GetContext::kMerge && db_statistics_ != nullptr) { get_context.ReportCounters(); } else { if (iter->max_covering_tombstone_seq > 0) { // The remaining files we look at will only contain covered keys, so // we stop here for this key file_picker_range.SkipKey(iter); } } switch (get_context.State()) { case GetContext::kNotFound: // Keep searching in other files break; case GetContext::kMerge: // TODO: update per-level perfcontext user_key_return_count for kMerge break; case GetContext::kFound: if (fp.GetHitFileLevel() == 0) { RecordTick(db_statistics_, GET_HIT_L0); } else if (fp.GetHitFileLevel() == 1) { RecordTick(db_statistics_, GET_HIT_L1); } else if (fp.GetHitFileLevel() >= 2) { RecordTick(db_statistics_, GET_HIT_L2_AND_UP); } PERF_COUNTER_BY_LEVEL_ADD(user_key_return_count, 1, fp.GetHitFileLevel()); file_range.MarkKeyDone(iter); if (iter->is_blob_index) { if (iter->value) { *status = GetBlob(read_options, iter->ukey_with_ts, *iter->value, iter->value); if (!status->ok()) { if (status->IsIncomplete()) { get_context.MarkKeyMayExist(); } continue; } } } file_range.AddValueSize(iter->value->size()); if (file_range.GetValueSize() > read_options.value_size_soft_limit) { s = Status::Aborted(); break; } continue; case GetContext::kDeleted: // Use empty error message for speed *status = Status::NotFound(); file_range.MarkKeyDone(iter); continue; case GetContext::kCorrupt: *status = Status::Corruption("corrupted key for ", iter->lkey->user_key()); file_range.MarkKeyDone(iter); continue; case GetContext::kUnexpectedBlobIndex: ROCKS_LOG_ERROR(info_log_, "Encounter unexpected blob index."); *status = Status::NotSupported( "Encounter unexpected blob index. Please open DB with " "ROCKSDB_NAMESPACE::blob_db::BlobDB instead."); file_range.MarkKeyDone(iter); continue; } } // Report MultiGet stats per level. if (fp.IsHitFileLastInLevel()) { // Dump the stats if this is the last file of this level and reset for // next level. RecordInHistogram(db_statistics_, NUM_INDEX_AND_FILTER_BLOCKS_READ_PER_LEVEL, num_index_read + num_filter_read); RecordInHistogram(db_statistics_, NUM_DATA_BLOCKS_READ_PER_LEVEL, num_data_read); RecordInHistogram(db_statistics_, NUM_SST_READ_PER_LEVEL, num_sst_read); num_filter_read = 0; num_index_read = 0; num_data_read = 0; num_sst_read = 0; } RecordInHistogram(db_statistics_, SST_BATCH_SIZE, batch_size); if (!s.ok() || file_picker_range.empty()) { break; } f = fp.GetNextFile(); } // Process any left over keys for (auto iter = range->begin(); s.ok() && iter != range->end(); ++iter) { GetContext& get_context = *iter->get_context; Status* status = iter->s; Slice user_key = iter->lkey->user_key(); if (db_statistics_ != nullptr) { get_context.ReportCounters(); } if (GetContext::kMerge == get_context.State()) { if (!merge_operator_) { *status = Status::InvalidArgument( "merge_operator is not properly initialized."); range->MarkKeyDone(iter); continue; } // merge_operands are in saver and we hit the beginning of the key history // do a final merge of nullptr and operands; std::string* str_value = iter->value != nullptr ? iter->value->GetSelf() : nullptr; *status = MergeHelper::TimedFullMerge( merge_operator_, user_key, nullptr, iter->merge_context.GetOperands(), str_value, info_log_, db_statistics_, clock_, nullptr /* result_operand */, true); if (LIKELY(iter->value != nullptr)) { iter->value->PinSelf(); range->AddValueSize(iter->value->size()); range->MarkKeyDone(iter); if (range->GetValueSize() > read_options.value_size_soft_limit) { s = Status::Aborted(); break; } } } else { range->MarkKeyDone(iter); *status = Status::NotFound(); // Use an empty error message for speed } } for (auto iter = range->begin(); iter != range->end(); ++iter) { range->MarkKeyDone(iter); *(iter->s) = s; } } bool Version::IsFilterSkipped(int level, bool is_file_last_in_level) { // Reaching the bottom level implies misses at all upper levels, so we'll // skip checking the filters when we predict a hit. return cfd_->ioptions()->optimize_filters_for_hits && (level > 0 || is_file_last_in_level) && level == storage_info_.num_non_empty_levels() - 1; } void VersionStorageInfo::GenerateLevelFilesBrief() { level_files_brief_.resize(num_non_empty_levels_); for (int level = 0; level < num_non_empty_levels_; level++) { DoGenerateLevelFilesBrief( &level_files_brief_[level], files_[level], &arena_); } } void Version::PrepareApply( const MutableCFOptions& mutable_cf_options, bool update_stats) { TEST_SYNC_POINT_CALLBACK( "Version::PrepareApply:forced_check", reinterpret_cast(&storage_info_.force_consistency_checks_)); UpdateAccumulatedStats(update_stats); storage_info_.UpdateNumNonEmptyLevels(); storage_info_.CalculateBaseBytes(*cfd_->ioptions(), mutable_cf_options); storage_info_.UpdateFilesByCompactionPri(cfd_->ioptions()->compaction_pri); storage_info_.GenerateFileIndexer(); storage_info_.GenerateLevelFilesBrief(); storage_info_.GenerateLevel0NonOverlapping(); storage_info_.GenerateBottommostFiles(); } bool Version::MaybeInitializeFileMetaData(FileMetaData* file_meta) { if (file_meta->init_stats_from_file || file_meta->compensated_file_size > 0) { return false; } std::shared_ptr tp; Status s = GetTableProperties(&tp, file_meta); file_meta->init_stats_from_file = true; if (!s.ok()) { ROCKS_LOG_ERROR(vset_->db_options_->info_log, "Unable to load table properties for file %" PRIu64 " --- %s\n", file_meta->fd.GetNumber(), s.ToString().c_str()); return false; } if (tp.get() == nullptr) return false; file_meta->num_entries = tp->num_entries; file_meta->num_deletions = tp->num_deletions; file_meta->raw_value_size = tp->raw_value_size; file_meta->raw_key_size = tp->raw_key_size; return true; } void VersionStorageInfo::UpdateAccumulatedStats(FileMetaData* file_meta) { TEST_SYNC_POINT_CALLBACK("VersionStorageInfo::UpdateAccumulatedStats", nullptr); assert(file_meta->init_stats_from_file); accumulated_file_size_ += file_meta->fd.GetFileSize(); accumulated_raw_key_size_ += file_meta->raw_key_size; accumulated_raw_value_size_ += file_meta->raw_value_size; accumulated_num_non_deletions_ += file_meta->num_entries - file_meta->num_deletions; accumulated_num_deletions_ += file_meta->num_deletions; current_num_non_deletions_ += file_meta->num_entries - file_meta->num_deletions; current_num_deletions_ += file_meta->num_deletions; current_num_samples_++; } void VersionStorageInfo::RemoveCurrentStats(FileMetaData* file_meta) { if (file_meta->init_stats_from_file) { current_num_non_deletions_ -= file_meta->num_entries - file_meta->num_deletions; current_num_deletions_ -= file_meta->num_deletions; current_num_samples_--; } } void Version::UpdateAccumulatedStats(bool update_stats) { if (update_stats) { // maximum number of table properties loaded from files. const int kMaxInitCount = 20; int init_count = 0; // here only the first kMaxInitCount files which haven't been // initialized from file will be updated with num_deletions. // The motivation here is to cap the maximum I/O per Version creation. // The reason for choosing files from lower-level instead of higher-level // is that such design is able to propagate the initialization from // lower-level to higher-level: When the num_deletions of lower-level // files are updated, it will make the lower-level files have accurate // compensated_file_size, making lower-level to higher-level compaction // will be triggered, which creates higher-level files whose num_deletions // will be updated here. for (int level = 0; level < storage_info_.num_levels_ && init_count < kMaxInitCount; ++level) { for (auto* file_meta : storage_info_.files_[level]) { if (MaybeInitializeFileMetaData(file_meta)) { // each FileMeta will be initialized only once. storage_info_.UpdateAccumulatedStats(file_meta); // when option "max_open_files" is -1, all the file metadata has // already been read, so MaybeInitializeFileMetaData() won't incur // any I/O cost. "max_open_files=-1" means that the table cache passed // to the VersionSet and then to the ColumnFamilySet has a size of // TableCache::kInfiniteCapacity if (vset_->GetColumnFamilySet()->get_table_cache()->GetCapacity() == TableCache::kInfiniteCapacity) { continue; } if (++init_count >= kMaxInitCount) { break; } } } } // In case all sampled-files contain only deletion entries, then we // load the table-property of a file in higher-level to initialize // that value. for (int level = storage_info_.num_levels_ - 1; storage_info_.accumulated_raw_value_size_ == 0 && level >= 0; --level) { for (int i = static_cast(storage_info_.files_[level].size()) - 1; storage_info_.accumulated_raw_value_size_ == 0 && i >= 0; --i) { if (MaybeInitializeFileMetaData(storage_info_.files_[level][i])) { storage_info_.UpdateAccumulatedStats(storage_info_.files_[level][i]); } } } } storage_info_.ComputeCompensatedSizes(); } void VersionStorageInfo::ComputeCompensatedSizes() { static const int kDeletionWeightOnCompaction = 2; uint64_t average_value_size = GetAverageValueSize(); // compute the compensated size for (int level = 0; level < num_levels_; level++) { for (auto* file_meta : files_[level]) { // Here we only compute compensated_file_size for those file_meta // which compensated_file_size is uninitialized (== 0). This is true only // for files that have been created right now and no other thread has // access to them. That's why we can safely mutate compensated_file_size. if (file_meta->compensated_file_size == 0) { file_meta->compensated_file_size = file_meta->fd.GetFileSize(); // Here we only boost the size of deletion entries of a file only // when the number of deletion entries is greater than the number of // non-deletion entries in the file. The motivation here is that in // a stable workload, the number of deletion entries should be roughly // equal to the number of non-deletion entries. If we compensate the // size of deletion entries in a stable workload, the deletion // compensation logic might introduce unwanted effet which changes the // shape of LSM tree. if (file_meta->num_deletions * 2 >= file_meta->num_entries) { file_meta->compensated_file_size += (file_meta->num_deletions * 2 - file_meta->num_entries) * average_value_size * kDeletionWeightOnCompaction; } } } } } int VersionStorageInfo::MaxInputLevel() const { if (compaction_style_ == kCompactionStyleLevel) { return num_levels() - 2; } return 0; } int VersionStorageInfo::MaxOutputLevel(bool allow_ingest_behind) const { if (allow_ingest_behind) { assert(num_levels() > 1); return num_levels() - 2; } return num_levels() - 1; } void VersionStorageInfo::EstimateCompactionBytesNeeded( const MutableCFOptions& mutable_cf_options) { // Only implemented for level-based compaction if (compaction_style_ != kCompactionStyleLevel) { estimated_compaction_needed_bytes_ = 0; return; } // Start from Level 0, if level 0 qualifies compaction to level 1, // we estimate the size of compaction. // Then we move on to the next level and see whether it qualifies compaction // to the next level. The size of the level is estimated as the actual size // on the level plus the input bytes from the previous level if there is any. // If it exceeds, take the exceeded bytes as compaction input and add the size // of the compaction size to tatal size. // We keep doing it to Level 2, 3, etc, until the last level and return the // accumulated bytes. uint64_t bytes_compact_to_next_level = 0; uint64_t level_size = 0; for (auto* f : files_[0]) { level_size += f->fd.GetFileSize(); } // Level 0 bool level0_compact_triggered = false; if (static_cast(files_[0].size()) >= mutable_cf_options.level0_file_num_compaction_trigger || level_size >= mutable_cf_options.max_bytes_for_level_base) { level0_compact_triggered = true; estimated_compaction_needed_bytes_ = level_size; bytes_compact_to_next_level = level_size; } else { estimated_compaction_needed_bytes_ = 0; } // Level 1 and up. uint64_t bytes_next_level = 0; for (int level = base_level(); level <= MaxInputLevel(); level++) { level_size = 0; if (bytes_next_level > 0) { #ifndef NDEBUG uint64_t level_size2 = 0; for (auto* f : files_[level]) { level_size2 += f->fd.GetFileSize(); } assert(level_size2 == bytes_next_level); #endif level_size = bytes_next_level; bytes_next_level = 0; } else { for (auto* f : files_[level]) { level_size += f->fd.GetFileSize(); } } if (level == base_level() && level0_compact_triggered) { // Add base level size to compaction if level0 compaction triggered. estimated_compaction_needed_bytes_ += level_size; } // Add size added by previous compaction level_size += bytes_compact_to_next_level; bytes_compact_to_next_level = 0; uint64_t level_target = MaxBytesForLevel(level); if (level_size > level_target) { bytes_compact_to_next_level = level_size - level_target; // Estimate the actual compaction fan-out ratio as size ratio between // the two levels. assert(bytes_next_level == 0); if (level + 1 < num_levels_) { for (auto* f : files_[level + 1]) { bytes_next_level += f->fd.GetFileSize(); } } if (bytes_next_level > 0) { assert(level_size > 0); estimated_compaction_needed_bytes_ += static_cast( static_cast(bytes_compact_to_next_level) * (static_cast(bytes_next_level) / static_cast(level_size) + 1)); } } } } namespace { uint32_t GetExpiredTtlFilesCount(const ImmutableCFOptions& ioptions, const MutableCFOptions& mutable_cf_options, const std::vector& files) { uint32_t ttl_expired_files_count = 0; int64_t _current_time; auto status = ioptions.env->GetCurrentTime(&_current_time); if (status.ok()) { const uint64_t current_time = static_cast(_current_time); for (FileMetaData* f : files) { if (!f->being_compacted) { uint64_t oldest_ancester_time = f->TryGetOldestAncesterTime(); if (oldest_ancester_time != 0 && oldest_ancester_time < (current_time - mutable_cf_options.ttl)) { ttl_expired_files_count++; } } } } return ttl_expired_files_count; } } // anonymous namespace void VersionStorageInfo::ComputeCompactionScore( const ImmutableCFOptions& immutable_cf_options, const MutableCFOptions& mutable_cf_options) { for (int level = 0; level <= MaxInputLevel(); level++) { double score; if (level == 0) { // We treat level-0 specially by bounding the number of files // instead of number of bytes for two reasons: // // (1) With larger write-buffer sizes, it is nice not to do too // many level-0 compactions. // // (2) The files in level-0 are merged on every read and // therefore we wish to avoid too many files when the individual // file size is small (perhaps because of a small write-buffer // setting, or very high compression ratios, or lots of // overwrites/deletions). int num_sorted_runs = 0; uint64_t total_size = 0; for (auto* f : files_[level]) { if (!f->being_compacted) { total_size += f->compensated_file_size; num_sorted_runs++; } } if (compaction_style_ == kCompactionStyleUniversal) { // For universal compaction, we use level0 score to indicate // compaction score for the whole DB. Adding other levels as if // they are L0 files. for (int i = 1; i < num_levels(); i++) { // Its possible that a subset of the files in a level may be in a // compaction, due to delete triggered compaction or trivial move. // In that case, the below check may not catch a level being // compacted as it only checks the first file. The worst that can // happen is a scheduled compaction thread will find nothing to do. if (!files_[i].empty() && !files_[i][0]->being_compacted) { num_sorted_runs++; } } } if (compaction_style_ == kCompactionStyleFIFO) { score = static_cast(total_size) / mutable_cf_options.compaction_options_fifo.max_table_files_size; if (mutable_cf_options.compaction_options_fifo.allow_compaction) { score = std::max( static_cast(num_sorted_runs) / mutable_cf_options.level0_file_num_compaction_trigger, score); } if (mutable_cf_options.ttl > 0) { score = std::max( static_cast(GetExpiredTtlFilesCount( immutable_cf_options, mutable_cf_options, files_[level])), score); } } else { score = static_cast(num_sorted_runs) / mutable_cf_options.level0_file_num_compaction_trigger; if (compaction_style_ == kCompactionStyleLevel && num_levels() > 1) { // Level-based involves L0->L0 compactions that can lead to oversized // L0 files. Take into account size as well to avoid later giant // compactions to the base level. uint64_t l0_target_size = mutable_cf_options.max_bytes_for_level_base; if (immutable_cf_options.level_compaction_dynamic_level_bytes && level_multiplier_ != 0.0) { // Prevent L0 to Lbase fanout from growing larger than // `level_multiplier_`. This prevents us from getting stuck picking // L0 forever even when it is hurting write-amp. That could happen // in dynamic level compaction's write-burst mode where the base // level's target size can grow to be enormous. l0_target_size = std::max(l0_target_size, static_cast(level_max_bytes_[base_level_] / level_multiplier_)); } score = std::max(score, static_cast(total_size) / l0_target_size); } } } else { // Compute the ratio of current size to size limit. uint64_t level_bytes_no_compacting = 0; for (auto f : files_[level]) { if (!f->being_compacted) { level_bytes_no_compacting += f->compensated_file_size; } } score = static_cast(level_bytes_no_compacting) / MaxBytesForLevel(level); } compaction_level_[level] = level; compaction_score_[level] = score; } // sort all the levels based on their score. Higher scores get listed // first. Use bubble sort because the number of entries are small. for (int i = 0; i < num_levels() - 2; i++) { for (int j = i + 1; j < num_levels() - 1; j++) { if (compaction_score_[i] < compaction_score_[j]) { double score = compaction_score_[i]; int level = compaction_level_[i]; compaction_score_[i] = compaction_score_[j]; compaction_level_[i] = compaction_level_[j]; compaction_score_[j] = score; compaction_level_[j] = level; } } } ComputeFilesMarkedForCompaction(); ComputeBottommostFilesMarkedForCompaction(); if (mutable_cf_options.ttl > 0) { ComputeExpiredTtlFiles(immutable_cf_options, mutable_cf_options.ttl); } if (mutable_cf_options.periodic_compaction_seconds > 0) { ComputeFilesMarkedForPeriodicCompaction( immutable_cf_options, mutable_cf_options.periodic_compaction_seconds); } EstimateCompactionBytesNeeded(mutable_cf_options); } void VersionStorageInfo::ComputeFilesMarkedForCompaction() { files_marked_for_compaction_.clear(); int last_qualify_level = 0; // Do not include files from the last level with data // If table properties collector suggests a file on the last level, // we should not move it to a new level. for (int level = num_levels() - 1; level >= 1; level--) { if (!files_[level].empty()) { last_qualify_level = level - 1; break; } } for (int level = 0; level <= last_qualify_level; level++) { for (auto* f : files_[level]) { if (!f->being_compacted && f->marked_for_compaction) { files_marked_for_compaction_.emplace_back(level, f); } } } } void VersionStorageInfo::ComputeExpiredTtlFiles( const ImmutableCFOptions& ioptions, const uint64_t ttl) { assert(ttl > 0); expired_ttl_files_.clear(); int64_t _current_time; auto status = ioptions.env->GetCurrentTime(&_current_time); if (!status.ok()) { return; } const uint64_t current_time = static_cast(_current_time); for (int level = 0; level < num_levels() - 1; level++) { for (FileMetaData* f : files_[level]) { if (!f->being_compacted) { uint64_t oldest_ancester_time = f->TryGetOldestAncesterTime(); if (oldest_ancester_time > 0 && oldest_ancester_time < (current_time - ttl)) { expired_ttl_files_.emplace_back(level, f); } } } } } void VersionStorageInfo::ComputeFilesMarkedForPeriodicCompaction( const ImmutableCFOptions& ioptions, const uint64_t periodic_compaction_seconds) { assert(periodic_compaction_seconds > 0); files_marked_for_periodic_compaction_.clear(); int64_t temp_current_time; auto status = ioptions.env->GetCurrentTime(&temp_current_time); if (!status.ok()) { return; } const uint64_t current_time = static_cast(temp_current_time); // If periodic_compaction_seconds is larger than current time, periodic // compaction can't possibly be triggered. if (periodic_compaction_seconds > current_time) { return; } const uint64_t allowed_time_limit = current_time - periodic_compaction_seconds; for (int level = 0; level < num_levels(); level++) { for (auto f : files_[level]) { if (!f->being_compacted) { // Compute a file's modification time in the following order: // 1. Use file_creation_time table property if it is > 0. // 2. Use creation_time table property if it is > 0. // 3. Use file's mtime metadata if the above two table properties are 0. // Don't consider the file at all if the modification time cannot be // correctly determined based on the above conditions. uint64_t file_modification_time = f->TryGetFileCreationTime(); if (file_modification_time == kUnknownFileCreationTime) { file_modification_time = f->TryGetOldestAncesterTime(); } if (file_modification_time == kUnknownOldestAncesterTime) { auto file_path = TableFileName(ioptions.cf_paths, f->fd.GetNumber(), f->fd.GetPathId()); status = ioptions.env->GetFileModificationTime( file_path, &file_modification_time); if (!status.ok()) { ROCKS_LOG_WARN(ioptions.info_log, "Can't get file modification time: %s: %s", file_path.c_str(), status.ToString().c_str()); continue; } } if (file_modification_time > 0 && file_modification_time < allowed_time_limit) { files_marked_for_periodic_compaction_.emplace_back(level, f); } } } } } namespace { // used to sort files by size struct Fsize { size_t index; FileMetaData* file; }; // Compator that is used to sort files based on their size // In normal mode: descending size bool CompareCompensatedSizeDescending(const Fsize& first, const Fsize& second) { return (first.file->compensated_file_size > second.file->compensated_file_size); } } // anonymous namespace void VersionStorageInfo::AddFile(int level, FileMetaData* f) { auto& level_files = files_[level]; level_files.push_back(f); f->refs++; const uint64_t file_number = f->fd.GetNumber(); assert(file_locations_.find(file_number) == file_locations_.end()); file_locations_.emplace(file_number, FileLocation(level, level_files.size() - 1)); } void VersionStorageInfo::AddBlobFile( std::shared_ptr blob_file_meta) { assert(blob_file_meta); const uint64_t blob_file_number = blob_file_meta->GetBlobFileNumber(); auto it = blob_files_.lower_bound(blob_file_number); assert(it == blob_files_.end() || it->first != blob_file_number); blob_files_.insert( it, BlobFiles::value_type(blob_file_number, std::move(blob_file_meta))); } // Version::PrepareApply() need to be called before calling the function, or // following functions called: // 1. UpdateNumNonEmptyLevels(); // 2. CalculateBaseBytes(); // 3. UpdateFilesByCompactionPri(); // 4. GenerateFileIndexer(); // 5. GenerateLevelFilesBrief(); // 6. GenerateLevel0NonOverlapping(); // 7. GenerateBottommostFiles(); void VersionStorageInfo::SetFinalized() { finalized_ = true; #ifndef NDEBUG if (compaction_style_ != kCompactionStyleLevel) { // Not level based compaction. return; } assert(base_level_ < 0 || num_levels() == 1 || (base_level_ >= 1 && base_level_ < num_levels())); // Verify all levels newer than base_level are empty except L0 for (int level = 1; level < base_level(); level++) { assert(NumLevelBytes(level) == 0); } uint64_t max_bytes_prev_level = 0; for (int level = base_level(); level < num_levels() - 1; level++) { if (LevelFiles(level).size() == 0) { continue; } assert(MaxBytesForLevel(level) >= max_bytes_prev_level); max_bytes_prev_level = MaxBytesForLevel(level); } int num_empty_non_l0_level = 0; for (int level = 0; level < num_levels(); level++) { assert(LevelFiles(level).size() == 0 || LevelFiles(level).size() == LevelFilesBrief(level).num_files); if (level > 0 && NumLevelBytes(level) > 0) { num_empty_non_l0_level++; } if (LevelFiles(level).size() > 0) { assert(level < num_non_empty_levels()); } } assert(compaction_level_.size() > 0); assert(compaction_level_.size() == compaction_score_.size()); #endif } void VersionStorageInfo::UpdateNumNonEmptyLevels() { num_non_empty_levels_ = num_levels_; for (int i = num_levels_ - 1; i >= 0; i--) { if (files_[i].size() != 0) { return; } else { num_non_empty_levels_ = i; } } } namespace { // Sort `temp` based on ratio of overlapping size over file size void SortFileByOverlappingRatio( const InternalKeyComparator& icmp, const std::vector& files, const std::vector& next_level_files, std::vector* temp) { std::unordered_map file_to_order; auto next_level_it = next_level_files.begin(); for (auto& file : files) { uint64_t overlapping_bytes = 0; // Skip files in next level that is smaller than current file while (next_level_it != next_level_files.end() && icmp.Compare((*next_level_it)->largest, file->smallest) < 0) { next_level_it++; } while (next_level_it != next_level_files.end() && icmp.Compare((*next_level_it)->smallest, file->largest) < 0) { overlapping_bytes += (*next_level_it)->fd.file_size; if (icmp.Compare((*next_level_it)->largest, file->largest) > 0) { // next level file cross large boundary of current file. break; } next_level_it++; } assert(file->compensated_file_size != 0); file_to_order[file->fd.GetNumber()] = overlapping_bytes * 1024u / file->compensated_file_size; } std::sort(temp->begin(), temp->end(), [&](const Fsize& f1, const Fsize& f2) -> bool { return file_to_order[f1.file->fd.GetNumber()] < file_to_order[f2.file->fd.GetNumber()]; }); } } // namespace void VersionStorageInfo::UpdateFilesByCompactionPri( CompactionPri compaction_pri) { if (compaction_style_ == kCompactionStyleNone || compaction_style_ == kCompactionStyleFIFO || compaction_style_ == kCompactionStyleUniversal) { // don't need this return; } // No need to sort the highest level because it is never compacted. for (int level = 0; level < num_levels() - 1; level++) { const std::vector& files = files_[level]; auto& files_by_compaction_pri = files_by_compaction_pri_[level]; assert(files_by_compaction_pri.size() == 0); // populate a temp vector for sorting based on size std::vector temp(files.size()); for (size_t i = 0; i < files.size(); i++) { temp[i].index = i; temp[i].file = files[i]; } // sort the top number_of_files_to_sort_ based on file size size_t num = VersionStorageInfo::kNumberFilesToSort; if (num > temp.size()) { num = temp.size(); } switch (compaction_pri) { case kByCompensatedSize: std::partial_sort(temp.begin(), temp.begin() + num, temp.end(), CompareCompensatedSizeDescending); break; case kOldestLargestSeqFirst: std::sort(temp.begin(), temp.end(), [](const Fsize& f1, const Fsize& f2) -> bool { return f1.file->fd.largest_seqno < f2.file->fd.largest_seqno; }); break; case kOldestSmallestSeqFirst: std::sort(temp.begin(), temp.end(), [](const Fsize& f1, const Fsize& f2) -> bool { return f1.file->fd.smallest_seqno < f2.file->fd.smallest_seqno; }); break; case kMinOverlappingRatio: SortFileByOverlappingRatio(*internal_comparator_, files_[level], files_[level + 1], &temp); break; default: assert(false); } assert(temp.size() == files.size()); // initialize files_by_compaction_pri_ for (size_t i = 0; i < temp.size(); i++) { files_by_compaction_pri.push_back(static_cast(temp[i].index)); } next_file_to_compact_by_size_[level] = 0; assert(files_[level].size() == files_by_compaction_pri_[level].size()); } } void VersionStorageInfo::GenerateLevel0NonOverlapping() { assert(!finalized_); level0_non_overlapping_ = true; if (level_files_brief_.size() == 0) { return; } // A copy of L0 files sorted by smallest key std::vector level0_sorted_file( level_files_brief_[0].files, level_files_brief_[0].files + level_files_brief_[0].num_files); std::sort(level0_sorted_file.begin(), level0_sorted_file.end(), [this](const FdWithKeyRange& f1, const FdWithKeyRange& f2) -> bool { return (internal_comparator_->Compare(f1.smallest_key, f2.smallest_key) < 0); }); for (size_t i = 1; i < level0_sorted_file.size(); ++i) { FdWithKeyRange& f = level0_sorted_file[i]; FdWithKeyRange& prev = level0_sorted_file[i - 1]; if (internal_comparator_->Compare(prev.largest_key, f.smallest_key) >= 0) { level0_non_overlapping_ = false; break; } } } void VersionStorageInfo::GenerateBottommostFiles() { assert(!finalized_); assert(bottommost_files_.empty()); for (size_t level = 0; level < level_files_brief_.size(); ++level) { for (size_t file_idx = 0; file_idx < level_files_brief_[level].num_files; ++file_idx) { const FdWithKeyRange& f = level_files_brief_[level].files[file_idx]; int l0_file_idx; if (level == 0) { l0_file_idx = static_cast(file_idx); } else { l0_file_idx = -1; } Slice smallest_user_key = ExtractUserKey(f.smallest_key); Slice largest_user_key = ExtractUserKey(f.largest_key); if (!RangeMightExistAfterSortedRun(smallest_user_key, largest_user_key, static_cast(level), l0_file_idx)) { bottommost_files_.emplace_back(static_cast(level), f.file_metadata); } } } } void VersionStorageInfo::UpdateOldestSnapshot(SequenceNumber seqnum) { assert(seqnum >= oldest_snapshot_seqnum_); oldest_snapshot_seqnum_ = seqnum; if (oldest_snapshot_seqnum_ > bottommost_files_mark_threshold_) { ComputeBottommostFilesMarkedForCompaction(); } } void VersionStorageInfo::ComputeBottommostFilesMarkedForCompaction() { bottommost_files_marked_for_compaction_.clear(); bottommost_files_mark_threshold_ = kMaxSequenceNumber; for (auto& level_and_file : bottommost_files_) { if (!level_and_file.second->being_compacted && level_and_file.second->fd.largest_seqno != 0 && level_and_file.second->num_deletions > 1) { // largest_seqno might be nonzero due to containing the final key in an // earlier compaction, whose seqnum we didn't zero out. Multiple deletions // ensures the file really contains deleted or overwritten keys. if (level_and_file.second->fd.largest_seqno < oldest_snapshot_seqnum_) { bottommost_files_marked_for_compaction_.push_back(level_and_file); } else { bottommost_files_mark_threshold_ = std::min(bottommost_files_mark_threshold_, level_and_file.second->fd.largest_seqno); } } } } void Version::Ref() { ++refs_; } bool Version::Unref() { assert(refs_ >= 1); --refs_; if (refs_ == 0) { delete this; return true; } return false; } bool VersionStorageInfo::OverlapInLevel(int level, const Slice* smallest_user_key, const Slice* largest_user_key) { if (level >= num_non_empty_levels_) { // empty level, no overlap return false; } return SomeFileOverlapsRange(*internal_comparator_, (level > 0), level_files_brief_[level], smallest_user_key, largest_user_key); } // Store in "*inputs" all files in "level" that overlap [begin,end] // If hint_index is specified, then it points to a file in the // overlapping range. // The file_index returns a pointer to any file in an overlapping range. void VersionStorageInfo::GetOverlappingInputs( int level, const InternalKey* begin, const InternalKey* end, std::vector* inputs, int hint_index, int* file_index, bool expand_range, InternalKey** next_smallest) const { if (level >= num_non_empty_levels_) { // this level is empty, no overlapping inputs return; } inputs->clear(); if (file_index) { *file_index = -1; } const Comparator* user_cmp = user_comparator_; if (level > 0) { GetOverlappingInputsRangeBinarySearch(level, begin, end, inputs, hint_index, file_index, false, next_smallest); return; } if (next_smallest) { // next_smallest key only makes sense for non-level 0, where files are // non-overlapping *next_smallest = nullptr; } Slice user_begin, user_end; if (begin != nullptr) { user_begin = begin->user_key(); } if (end != nullptr) { user_end = end->user_key(); } // index stores the file index need to check. std::list index; for (size_t i = 0; i < level_files_brief_[level].num_files; i++) { index.emplace_back(i); } while (!index.empty()) { bool found_overlapping_file = false; auto iter = index.begin(); while (iter != index.end()) { FdWithKeyRange* f = &(level_files_brief_[level].files[*iter]); const Slice file_start = ExtractUserKey(f->smallest_key); const Slice file_limit = ExtractUserKey(f->largest_key); if (begin != nullptr && user_cmp->CompareWithoutTimestamp(file_limit, user_begin) < 0) { // "f" is completely before specified range; skip it iter++; } else if (end != nullptr && user_cmp->CompareWithoutTimestamp(file_start, user_end) > 0) { // "f" is completely after specified range; skip it iter++; } else { // if overlap inputs->emplace_back(files_[level][*iter]); found_overlapping_file = true; // record the first file index. if (file_index && *file_index == -1) { *file_index = static_cast(*iter); } // the related file is overlap, erase to avoid checking again. iter = index.erase(iter); if (expand_range) { if (begin != nullptr && user_cmp->CompareWithoutTimestamp(file_start, user_begin) < 0) { user_begin = file_start; } if (end != nullptr && user_cmp->CompareWithoutTimestamp(file_limit, user_end) > 0) { user_end = file_limit; } } } } // if all the files left are not overlap, break if (!found_overlapping_file) { break; } } } // Store in "*inputs" files in "level" that within range [begin,end] // Guarantee a "clean cut" boundary between the files in inputs // and the surrounding files and the maxinum number of files. // This will ensure that no parts of a key are lost during compaction. // If hint_index is specified, then it points to a file in the range. // The file_index returns a pointer to any file in an overlapping range. void VersionStorageInfo::GetCleanInputsWithinInterval( int level, const InternalKey* begin, const InternalKey* end, std::vector* inputs, int hint_index, int* file_index) const { inputs->clear(); if (file_index) { *file_index = -1; } if (level >= num_non_empty_levels_ || level == 0 || level_files_brief_[level].num_files == 0) { // this level is empty, no inputs within range // also don't support clean input interval within L0 return; } GetOverlappingInputsRangeBinarySearch(level, begin, end, inputs, hint_index, file_index, true /* within_interval */); } // Store in "*inputs" all files in "level" that overlap [begin,end] // Employ binary search to find at least one file that overlaps the // specified range. From that file, iterate backwards and // forwards to find all overlapping files. // if within_range is set, then only store the maximum clean inputs // within range [begin, end]. "clean" means there is a boudnary // between the files in "*inputs" and the surrounding files void VersionStorageInfo::GetOverlappingInputsRangeBinarySearch( int level, const InternalKey* begin, const InternalKey* end, std::vector* inputs, int hint_index, int* file_index, bool within_interval, InternalKey** next_smallest) const { assert(level > 0); auto user_cmp = user_comparator_; const FdWithKeyRange* files = level_files_brief_[level].files; const int num_files = static_cast(level_files_brief_[level].num_files); // begin to use binary search to find lower bound // and upper bound. int start_index = 0; int end_index = num_files; if (begin != nullptr) { // if within_interval is true, with file_key would find // not overlapping ranges in std::lower_bound. auto cmp = [&user_cmp, &within_interval](const FdWithKeyRange& f, const InternalKey* k) { auto& file_key = within_interval ? f.file_metadata->smallest : f.file_metadata->largest; return sstableKeyCompare(user_cmp, file_key, *k) < 0; }; start_index = static_cast( std::lower_bound(files, files + (hint_index == -1 ? num_files : hint_index), begin, cmp) - files); if (start_index > 0 && within_interval) { bool is_overlapping = true; while (is_overlapping && start_index < num_files) { auto& pre_limit = files[start_index - 1].file_metadata->largest; auto& cur_start = files[start_index].file_metadata->smallest; is_overlapping = sstableKeyCompare(user_cmp, pre_limit, cur_start) == 0; start_index += is_overlapping; } } } if (end != nullptr) { // if within_interval is true, with file_key would find // not overlapping ranges in std::upper_bound. auto cmp = [&user_cmp, &within_interval](const InternalKey* k, const FdWithKeyRange& f) { auto& file_key = within_interval ? f.file_metadata->largest : f.file_metadata->smallest; return sstableKeyCompare(user_cmp, *k, file_key) < 0; }; end_index = static_cast( std::upper_bound(files + start_index, files + num_files, end, cmp) - files); if (end_index < num_files && within_interval) { bool is_overlapping = true; while (is_overlapping && end_index > start_index) { auto& next_start = files[end_index].file_metadata->smallest; auto& cur_limit = files[end_index - 1].file_metadata->largest; is_overlapping = sstableKeyCompare(user_cmp, cur_limit, next_start) == 0; end_index -= is_overlapping; } } } assert(start_index <= end_index); // If there were no overlapping files, return immediately. if (start_index == end_index) { if (next_smallest) { *next_smallest = nullptr; } return; } assert(start_index < end_index); // returns the index where an overlap is found if (file_index) { *file_index = start_index; } // insert overlapping files into vector for (int i = start_index; i < end_index; i++) { inputs->push_back(files_[level][i]); } if (next_smallest != nullptr) { // Provide the next key outside the range covered by inputs if (end_index < static_cast(files_[level].size())) { **next_smallest = files_[level][end_index]->smallest; } else { *next_smallest = nullptr; } } } uint64_t VersionStorageInfo::NumLevelBytes(int level) const { assert(level >= 0); assert(level < num_levels()); return TotalFileSize(files_[level]); } const char* VersionStorageInfo::LevelSummary( LevelSummaryStorage* scratch) const { int len = 0; if (compaction_style_ == kCompactionStyleLevel && num_levels() > 1) { assert(base_level_ < static_cast(level_max_bytes_.size())); if (level_multiplier_ != 0.0) { len = snprintf( scratch->buffer, sizeof(scratch->buffer), "base level %d level multiplier %.2f max bytes base %" PRIu64 " ", base_level_, level_multiplier_, level_max_bytes_[base_level_]); } } len += snprintf(scratch->buffer + len, sizeof(scratch->buffer) - len, "files["); for (int i = 0; i < num_levels(); i++) { int sz = sizeof(scratch->buffer) - len; int ret = snprintf(scratch->buffer + len, sz, "%d ", int(files_[i].size())); if (ret < 0 || ret >= sz) break; len += ret; } if (len > 0) { // overwrite the last space --len; } len += snprintf(scratch->buffer + len, sizeof(scratch->buffer) - len, "] max score %.2f", compaction_score_[0]); if (!files_marked_for_compaction_.empty()) { snprintf(scratch->buffer + len, sizeof(scratch->buffer) - len, " (%" ROCKSDB_PRIszt " files need compaction)", files_marked_for_compaction_.size()); } return scratch->buffer; } const char* VersionStorageInfo::LevelFileSummary(FileSummaryStorage* scratch, int level) const { int len = snprintf(scratch->buffer, sizeof(scratch->buffer), "files_size["); for (const auto& f : files_[level]) { int sz = sizeof(scratch->buffer) - len; char sztxt[16]; AppendHumanBytes(f->fd.GetFileSize(), sztxt, sizeof(sztxt)); int ret = snprintf(scratch->buffer + len, sz, "#%" PRIu64 "(seq=%" PRIu64 ",sz=%s,%d) ", f->fd.GetNumber(), f->fd.smallest_seqno, sztxt, static_cast(f->being_compacted)); if (ret < 0 || ret >= sz) break; len += ret; } // overwrite the last space (only if files_[level].size() is non-zero) if (files_[level].size() && len > 0) { --len; } snprintf(scratch->buffer + len, sizeof(scratch->buffer) - len, "]"); return scratch->buffer; } int64_t VersionStorageInfo::MaxNextLevelOverlappingBytes() { uint64_t result = 0; std::vector overlaps; for (int level = 1; level < num_levels() - 1; level++) { for (const auto& f : files_[level]) { GetOverlappingInputs(level + 1, &f->smallest, &f->largest, &overlaps); const uint64_t sum = TotalFileSize(overlaps); if (sum > result) { result = sum; } } } return result; } uint64_t VersionStorageInfo::MaxBytesForLevel(int level) const { // Note: the result for level zero is not really used since we set // the level-0 compaction threshold based on number of files. assert(level >= 0); assert(level < static_cast(level_max_bytes_.size())); return level_max_bytes_[level]; } void VersionStorageInfo::CalculateBaseBytes(const ImmutableCFOptions& ioptions, const MutableCFOptions& options) { // Special logic to set number of sorted runs. // It is to match the previous behavior when all files are in L0. int num_l0_count = static_cast(files_[0].size()); if (compaction_style_ == kCompactionStyleUniversal) { // For universal compaction, we use level0 score to indicate // compaction score for the whole DB. Adding other levels as if // they are L0 files. for (int i = 1; i < num_levels(); i++) { if (!files_[i].empty()) { num_l0_count++; } } } set_l0_delay_trigger_count(num_l0_count); level_max_bytes_.resize(ioptions.num_levels); if (!ioptions.level_compaction_dynamic_level_bytes) { base_level_ = (ioptions.compaction_style == kCompactionStyleLevel) ? 1 : -1; // Calculate for static bytes base case for (int i = 0; i < ioptions.num_levels; ++i) { if (i == 0 && ioptions.compaction_style == kCompactionStyleUniversal) { level_max_bytes_[i] = options.max_bytes_for_level_base; } else if (i > 1) { level_max_bytes_[i] = MultiplyCheckOverflow( MultiplyCheckOverflow(level_max_bytes_[i - 1], options.max_bytes_for_level_multiplier), options.MaxBytesMultiplerAdditional(i - 1)); } else { level_max_bytes_[i] = options.max_bytes_for_level_base; } } } else { uint64_t max_level_size = 0; int first_non_empty_level = -1; // Find size of non-L0 level of most data. // Cannot use the size of the last level because it can be empty or less // than previous levels after compaction. for (int i = 1; i < num_levels_; i++) { uint64_t total_size = 0; for (const auto& f : files_[i]) { total_size += f->fd.GetFileSize(); } if (total_size > 0 && first_non_empty_level == -1) { first_non_empty_level = i; } if (total_size > max_level_size) { max_level_size = total_size; } } // Prefill every level's max bytes to disallow compaction from there. for (int i = 0; i < num_levels_; i++) { level_max_bytes_[i] = std::numeric_limits::max(); } if (max_level_size == 0) { // No data for L1 and up. L0 compacts to last level directly. // No compaction from L1+ needs to be scheduled. base_level_ = num_levels_ - 1; } else { uint64_t l0_size = 0; for (const auto& f : files_[0]) { l0_size += f->fd.GetFileSize(); } uint64_t base_bytes_max = std::max(options.max_bytes_for_level_base, l0_size); uint64_t base_bytes_min = static_cast( base_bytes_max / options.max_bytes_for_level_multiplier); // Try whether we can make last level's target size to be max_level_size uint64_t cur_level_size = max_level_size; for (int i = num_levels_ - 2; i >= first_non_empty_level; i--) { // Round up after dividing cur_level_size = static_cast( cur_level_size / options.max_bytes_for_level_multiplier); } // Calculate base level and its size. uint64_t base_level_size; if (cur_level_size <= base_bytes_min) { // Case 1. If we make target size of last level to be max_level_size, // target size of the first non-empty level would be smaller than // base_bytes_min. We set it be base_bytes_min. base_level_size = base_bytes_min + 1U; base_level_ = first_non_empty_level; ROCKS_LOG_INFO(ioptions.info_log, "More existing levels in DB than needed. " "max_bytes_for_level_multiplier may not be guaranteed."); } else { // Find base level (where L0 data is compacted to). base_level_ = first_non_empty_level; while (base_level_ > 1 && cur_level_size > base_bytes_max) { --base_level_; cur_level_size = static_cast( cur_level_size / options.max_bytes_for_level_multiplier); } if (cur_level_size > base_bytes_max) { // Even L1 will be too large assert(base_level_ == 1); base_level_size = base_bytes_max; } else { base_level_size = cur_level_size; } } level_multiplier_ = options.max_bytes_for_level_multiplier; assert(base_level_size > 0); if (l0_size > base_level_size && (l0_size > options.max_bytes_for_level_base || static_cast(files_[0].size() / 2) >= options.level0_file_num_compaction_trigger)) { // We adjust the base level according to actual L0 size, and adjust // the level multiplier accordingly, when: // 1. the L0 size is larger than level size base, or // 2. number of L0 files reaches twice the L0->L1 compaction trigger // We don't do this otherwise to keep the LSM-tree structure stable // unless the L0 compation is backlogged. base_level_size = l0_size; if (base_level_ == num_levels_ - 1) { level_multiplier_ = 1.0; } else { level_multiplier_ = std::pow( static_cast(max_level_size) / static_cast(base_level_size), 1.0 / static_cast(num_levels_ - base_level_ - 1)); } } uint64_t level_size = base_level_size; for (int i = base_level_; i < num_levels_; i++) { if (i > base_level_) { level_size = MultiplyCheckOverflow(level_size, level_multiplier_); } // Don't set any level below base_bytes_max. Otherwise, the LSM can // assume an hourglass shape where L1+ sizes are smaller than L0. This // causes compaction scoring, which depends on level sizes, to favor L1+ // at the expense of L0, which may fill up and stall. level_max_bytes_[i] = std::max(level_size, base_bytes_max); } } } } uint64_t VersionStorageInfo::EstimateLiveDataSize() const { // Estimate the live data size by adding up the size of a maximal set of // sst files with no range overlap in same or higher level. The less // compacted, the more optimistic (smaller) this estimate is. Also, // for multiple sorted runs within a level, file order will matter. uint64_t size = 0; auto ikey_lt = [this](InternalKey* x, InternalKey* y) { return internal_comparator_->Compare(*x, *y) < 0; }; // (Ordered) map of largest keys in files being included in size estimate std::map ranges(ikey_lt); for (int l = num_levels_ - 1; l >= 0; l--) { bool found_end = false; for (auto file : files_[l]) { // Find the first file already included with largest key is larger than // the smallest key of `file`. If that file does not overlap with the // current file, none of the files in the map does. If there is // no potential overlap, we can safely insert the rest of this level // (if the level is not 0) into the map without checking again because // the elements in the level are sorted and non-overlapping. auto lb = (found_end && l != 0) ? ranges.end() : ranges.lower_bound(&file->smallest); found_end = (lb == ranges.end()); if (found_end || internal_comparator_->Compare( file->largest, (*lb).second->smallest) < 0) { ranges.emplace_hint(lb, &file->largest, file); size += file->fd.file_size; } } } return size; } bool VersionStorageInfo::RangeMightExistAfterSortedRun( const Slice& smallest_user_key, const Slice& largest_user_key, int last_level, int last_l0_idx) { assert((last_l0_idx != -1) == (last_level == 0)); // TODO(ajkr): this preserves earlier behavior where we considered an L0 file // bottommost only if it's the oldest L0 file and there are no files on older // levels. It'd be better to consider it bottommost if there's no overlap in // older levels/files. if (last_level == 0 && last_l0_idx != static_cast(LevelFiles(0).size() - 1)) { return true; } // Checks whether there are files living beyond the `last_level`. If lower // levels have files, it checks for overlap between [`smallest_key`, // `largest_key`] and those files. Bottomlevel optimizations can be made if // there are no files in lower levels or if there is no overlap with the files // in the lower levels. for (int level = last_level + 1; level < num_levels(); level++) { // The range is not in the bottommost level if there are files in lower // levels when the `last_level` is 0 or if there are files in lower levels // which overlap with [`smallest_key`, `largest_key`]. if (files_[level].size() > 0 && (last_level == 0 || OverlapInLevel(level, &smallest_user_key, &largest_user_key))) { return true; } } return false; } void Version::AddLiveFiles(std::vector* live_table_files, std::vector* live_blob_files) const { assert(live_table_files); assert(live_blob_files); for (int level = 0; level < storage_info_.num_levels(); ++level) { const auto& level_files = storage_info_.LevelFiles(level); for (const auto& meta : level_files) { assert(meta); live_table_files->emplace_back(meta->fd.GetNumber()); } } const auto& blob_files = storage_info_.GetBlobFiles(); for (const auto& pair : blob_files) { const auto& meta = pair.second; assert(meta); live_blob_files->emplace_back(meta->GetBlobFileNumber()); } } std::string Version::DebugString(bool hex, bool print_stats) const { std::string r; for (int level = 0; level < storage_info_.num_levels_; level++) { // E.g., // --- level 1 --- // 17:123[1 .. 124]['a' .. 'd'] // 20:43[124 .. 128]['e' .. 'g'] // // if print_stats=true: // 17:123[1 .. 124]['a' .. 'd'](4096) r.append("--- level "); AppendNumberTo(&r, level); r.append(" --- version# "); AppendNumberTo(&r, version_number_); r.append(" ---\n"); const std::vector& files = storage_info_.files_[level]; for (size_t i = 0; i < files.size(); i++) { r.push_back(' '); AppendNumberTo(&r, files[i]->fd.GetNumber()); r.push_back(':'); AppendNumberTo(&r, files[i]->fd.GetFileSize()); r.append("["); AppendNumberTo(&r, files[i]->fd.smallest_seqno); r.append(" .. "); AppendNumberTo(&r, files[i]->fd.largest_seqno); r.append("]"); r.append("["); r.append(files[i]->smallest.DebugString(hex)); r.append(" .. "); r.append(files[i]->largest.DebugString(hex)); r.append("]"); if (files[i]->oldest_blob_file_number != kInvalidBlobFileNumber) { r.append(" blob_file:"); AppendNumberTo(&r, files[i]->oldest_blob_file_number); } if (print_stats) { r.append("("); r.append(ToString( files[i]->stats.num_reads_sampled.load(std::memory_order_relaxed))); r.append(")"); } r.append("\n"); } } const auto& blob_files = storage_info_.GetBlobFiles(); if (!blob_files.empty()) { r.append("--- blob files --- version# "); AppendNumberTo(&r, version_number_); r.append(" ---\n"); for (const auto& pair : blob_files) { const auto& blob_file_meta = pair.second; assert(blob_file_meta); r.append(blob_file_meta->DebugString()); r.push_back('\n'); } } return r; } // this is used to batch writes to the manifest file struct VersionSet::ManifestWriter { Status status; bool done; InstrumentedCondVar cv; ColumnFamilyData* cfd; const MutableCFOptions mutable_cf_options; const autovector& edit_list; const std::function manifest_write_callback; explicit ManifestWriter( InstrumentedMutex* mu, ColumnFamilyData* _cfd, const MutableCFOptions& cf_options, const autovector& e, const std::function& manifest_wcb) : done(false), cv(mu), cfd(_cfd), mutable_cf_options(cf_options), edit_list(e), manifest_write_callback(manifest_wcb) {} ~ManifestWriter() { status.PermitUncheckedError(); } bool IsAllWalEdits() const { bool all_wal_edits = true; for (const auto& e : edit_list) { if (!e->IsWalManipulation()) { all_wal_edits = false; break; } } return all_wal_edits; } }; Status AtomicGroupReadBuffer::AddEdit(VersionEdit* edit) { assert(edit); if (edit->is_in_atomic_group_) { TEST_SYNC_POINT("AtomicGroupReadBuffer::AddEdit:AtomicGroup"); if (replay_buffer_.empty()) { replay_buffer_.resize(edit->remaining_entries_ + 1); TEST_SYNC_POINT_CALLBACK( "AtomicGroupReadBuffer::AddEdit:FirstInAtomicGroup", edit); } read_edits_in_atomic_group_++; if (read_edits_in_atomic_group_ + edit->remaining_entries_ != static_cast(replay_buffer_.size())) { TEST_SYNC_POINT_CALLBACK( "AtomicGroupReadBuffer::AddEdit:IncorrectAtomicGroupSize", edit); return Status::Corruption("corrupted atomic group"); } replay_buffer_[read_edits_in_atomic_group_ - 1] = *edit; if (read_edits_in_atomic_group_ == replay_buffer_.size()) { TEST_SYNC_POINT_CALLBACK( "AtomicGroupReadBuffer::AddEdit:LastInAtomicGroup", edit); return Status::OK(); } return Status::OK(); } // A normal edit. if (!replay_buffer().empty()) { TEST_SYNC_POINT_CALLBACK( "AtomicGroupReadBuffer::AddEdit:AtomicGroupMixedWithNormalEdits", edit); return Status::Corruption("corrupted atomic group"); } return Status::OK(); } bool AtomicGroupReadBuffer::IsFull() const { return read_edits_in_atomic_group_ == replay_buffer_.size(); } bool AtomicGroupReadBuffer::IsEmpty() const { return replay_buffer_.empty(); } void AtomicGroupReadBuffer::Clear() { read_edits_in_atomic_group_ = 0; replay_buffer_.clear(); } VersionSet::VersionSet(const std::string& dbname, const ImmutableDBOptions* _db_options, const FileOptions& storage_options, Cache* table_cache, WriteBufferManager* write_buffer_manager, WriteController* write_controller, BlockCacheTracer* const block_cache_tracer, const std::shared_ptr& io_tracer) : column_family_set_( new ColumnFamilySet(dbname, _db_options, storage_options, table_cache, write_buffer_manager, write_controller, block_cache_tracer, io_tracer)), table_cache_(table_cache), env_(_db_options->env), fs_(_db_options->fs, io_tracer), clock_(env_->GetSystemClock()), dbname_(dbname), db_options_(_db_options), next_file_number_(2), manifest_file_number_(0), // Filled by Recover() options_file_number_(0), pending_manifest_file_number_(0), last_sequence_(0), last_allocated_sequence_(0), last_published_sequence_(0), prev_log_number_(0), current_version_number_(0), manifest_file_size_(0), file_options_(storage_options), block_cache_tracer_(block_cache_tracer), io_tracer_(io_tracer) {} VersionSet::~VersionSet() { // we need to delete column_family_set_ because its destructor depends on // VersionSet column_family_set_.reset(); for (auto& file : obsolete_files_) { if (file.metadata->table_reader_handle) { table_cache_->Release(file.metadata->table_reader_handle); TableCache::Evict(table_cache_, file.metadata->fd.GetNumber()); } file.DeleteMetadata(); } obsolete_files_.clear(); io_status_.PermitUncheckedError(); } void VersionSet::Reset() { if (column_family_set_) { WriteBufferManager* wbm = column_family_set_->write_buffer_manager(); WriteController* wc = column_family_set_->write_controller(); column_family_set_.reset( new ColumnFamilySet(dbname_, db_options_, file_options_, table_cache_, wbm, wc, block_cache_tracer_, io_tracer_)); } db_id_.clear(); next_file_number_.store(2); min_log_number_to_keep_2pc_.store(0); manifest_file_number_ = 0; options_file_number_ = 0; pending_manifest_file_number_ = 0; last_sequence_.store(0); last_allocated_sequence_.store(0); last_published_sequence_.store(0); prev_log_number_ = 0; descriptor_log_.reset(); current_version_number_ = 0; manifest_writers_.clear(); manifest_file_size_ = 0; obsolete_files_.clear(); obsolete_manifests_.clear(); wals_.Reset(); } void VersionSet::AppendVersion(ColumnFamilyData* column_family_data, Version* v) { // compute new compaction score v->storage_info()->ComputeCompactionScore( *column_family_data->ioptions(), *column_family_data->GetLatestMutableCFOptions()); // Mark v finalized v->storage_info_.SetFinalized(); // Make "v" current assert(v->refs_ == 0); Version* current = column_family_data->current(); assert(v != current); if (current != nullptr) { assert(current->refs_ > 0); current->Unref(); } column_family_data->SetCurrent(v); v->Ref(); // Append to linked list v->prev_ = column_family_data->dummy_versions()->prev_; v->next_ = column_family_data->dummy_versions(); v->prev_->next_ = v; v->next_->prev_ = v; } Status VersionSet::ProcessManifestWrites( std::deque& writers, InstrumentedMutex* mu, FSDirectory* db_directory, bool new_descriptor_log, const ColumnFamilyOptions* new_cf_options) { mu->AssertHeld(); assert(!writers.empty()); ManifestWriter& first_writer = writers.front(); ManifestWriter* last_writer = &first_writer; assert(!manifest_writers_.empty()); assert(manifest_writers_.front() == &first_writer); autovector batch_edits; autovector versions; autovector mutable_cf_options_ptrs; std::vector> builder_guards; if (first_writer.edit_list.front()->IsColumnFamilyManipulation()) { // No group commits for column family add or drop LogAndApplyCFHelper(first_writer.edit_list.front()); batch_edits.push_back(first_writer.edit_list.front()); } else { auto it = manifest_writers_.cbegin(); size_t group_start = std::numeric_limits::max(); while (it != manifest_writers_.cend()) { if ((*it)->edit_list.front()->IsColumnFamilyManipulation()) { // no group commits for column family add or drop break; } last_writer = *(it++); assert(last_writer != nullptr); assert(last_writer->cfd != nullptr); if (last_writer->cfd->IsDropped()) { // If we detect a dropped CF at this point, and the corresponding // version edits belong to an atomic group, then we need to find out // the preceding version edits in the same atomic group, and update // their `remaining_entries_` member variable because we are NOT going // to write the version edits' of dropped CF to the MANIFEST. If we // don't update, then Recover can report corrupted atomic group because // the `remaining_entries_` do not match. if (!batch_edits.empty()) { if (batch_edits.back()->is_in_atomic_group_ && batch_edits.back()->remaining_entries_ > 0) { assert(group_start < batch_edits.size()); const auto& edit_list = last_writer->edit_list; size_t k = 0; while (k < edit_list.size()) { if (!edit_list[k]->is_in_atomic_group_) { break; } else if (edit_list[k]->remaining_entries_ == 0) { ++k; break; } ++k; } for (auto i = group_start; i < batch_edits.size(); ++i) { assert(static_cast(k) <= batch_edits.back()->remaining_entries_); batch_edits[i]->remaining_entries_ -= static_cast(k); } } } continue; } // We do a linear search on versions because versions is small. // TODO(yanqin) maybe consider unordered_map Version* version = nullptr; VersionBuilder* builder = nullptr; for (int i = 0; i != static_cast(versions.size()); ++i) { uint32_t cf_id = last_writer->cfd->GetID(); if (versions[i]->cfd()->GetID() == cf_id) { version = versions[i]; assert(!builder_guards.empty() && builder_guards.size() == versions.size()); builder = builder_guards[i]->version_builder(); TEST_SYNC_POINT_CALLBACK( "VersionSet::ProcessManifestWrites:SameColumnFamily", &cf_id); break; } } if (version == nullptr) { // WAL manipulations do not need to be applied to versions. if (!last_writer->IsAllWalEdits()) { version = new Version(last_writer->cfd, this, file_options_, last_writer->mutable_cf_options, io_tracer_, current_version_number_++); versions.push_back(version); mutable_cf_options_ptrs.push_back(&last_writer->mutable_cf_options); builder_guards.emplace_back( new BaseReferencedVersionBuilder(last_writer->cfd)); builder = builder_guards.back()->version_builder(); } assert(last_writer->IsAllWalEdits() || builder); assert(last_writer->IsAllWalEdits() || version); TEST_SYNC_POINT_CALLBACK("VersionSet::ProcessManifestWrites:NewVersion", version); } for (const auto& e : last_writer->edit_list) { if (e->is_in_atomic_group_) { if (batch_edits.empty() || !batch_edits.back()->is_in_atomic_group_ || (batch_edits.back()->is_in_atomic_group_ && batch_edits.back()->remaining_entries_ == 0)) { group_start = batch_edits.size(); } } else if (group_start != std::numeric_limits::max()) { group_start = std::numeric_limits::max(); } Status s = LogAndApplyHelper(last_writer->cfd, builder, e, mu); if (!s.ok()) { // free up the allocated memory for (auto v : versions) { delete v; } return s; } batch_edits.push_back(e); } } for (int i = 0; i < static_cast(versions.size()); ++i) { assert(!builder_guards.empty() && builder_guards.size() == versions.size()); auto* builder = builder_guards[i]->version_builder(); Status s = builder->SaveTo(versions[i]->storage_info()); if (!s.ok()) { // free up the allocated memory for (auto v : versions) { delete v; } return s; } } } #ifndef NDEBUG // Verify that version edits of atomic groups have correct // remaining_entries_. size_t k = 0; while (k < batch_edits.size()) { while (k < batch_edits.size() && !batch_edits[k]->is_in_atomic_group_) { ++k; } if (k == batch_edits.size()) { break; } size_t i = k; while (i < batch_edits.size()) { if (!batch_edits[i]->is_in_atomic_group_) { break; } assert(i - k + batch_edits[i]->remaining_entries_ == batch_edits[k]->remaining_entries_); if (batch_edits[i]->remaining_entries_ == 0) { ++i; break; } ++i; } assert(batch_edits[i - 1]->is_in_atomic_group_); assert(0 == batch_edits[i - 1]->remaining_entries_); std::vector tmp; for (size_t j = k; j != i; ++j) { tmp.emplace_back(batch_edits[j]); } TEST_SYNC_POINT_CALLBACK( "VersionSet::ProcessManifestWrites:CheckOneAtomicGroup", &tmp); k = i; } #endif // NDEBUG assert(pending_manifest_file_number_ == 0); if (!descriptor_log_ || manifest_file_size_ > db_options_->max_manifest_file_size) { TEST_SYNC_POINT("VersionSet::ProcessManifestWrites:BeforeNewManifest"); new_descriptor_log = true; } else { pending_manifest_file_number_ = manifest_file_number_; } // Local cached copy of state variable(s). WriteCurrentStateToManifest() // reads its content after releasing db mutex to avoid race with // SwitchMemtable(). std::unordered_map curr_state; VersionEdit wal_additions; if (new_descriptor_log) { pending_manifest_file_number_ = NewFileNumber(); batch_edits.back()->SetNextFile(next_file_number_.load()); // if we are writing out new snapshot make sure to persist max column // family. if (column_family_set_->GetMaxColumnFamily() > 0) { first_writer.edit_list.front()->SetMaxColumnFamily( column_family_set_->GetMaxColumnFamily()); } for (const auto* cfd : *column_family_set_) { assert(curr_state.find(cfd->GetID()) == curr_state.end()); curr_state.emplace(std::make_pair( cfd->GetID(), MutableCFState(cfd->GetLogNumber(), cfd->GetFullHistoryTsLow()))); } for (const auto& wal : wals_.GetWals()) { wal_additions.AddWal(wal.first, wal.second); } } uint64_t new_manifest_file_size = 0; Status s; IOStatus io_s; { FileOptions opt_file_opts = fs_->OptimizeForManifestWrite(file_options_); mu->Unlock(); TEST_SYNC_POINT_CALLBACK("VersionSet::LogAndApply:WriteManifest", nullptr); if (!first_writer.edit_list.front()->IsColumnFamilyManipulation()) { for (int i = 0; i < static_cast(versions.size()); ++i) { assert(!builder_guards.empty() && builder_guards.size() == versions.size()); assert(!mutable_cf_options_ptrs.empty() && builder_guards.size() == versions.size()); ColumnFamilyData* cfd = versions[i]->cfd_; s = builder_guards[i]->version_builder()->LoadTableHandlers( cfd->internal_stats(), 1 /* max_threads */, true /* prefetch_index_and_filter_in_cache */, false /* is_initial_load */, mutable_cf_options_ptrs[i]->prefix_extractor.get(), MaxFileSizeForL0MetaPin(*mutable_cf_options_ptrs[i])); if (!s.ok()) { if (db_options_->paranoid_checks) { break; } s = Status::OK(); } } } if (s.ok() && new_descriptor_log) { // This is fine because everything inside of this block is serialized -- // only one thread can be here at the same time // create new manifest file ROCKS_LOG_INFO(db_options_->info_log, "Creating manifest %" PRIu64 "\n", pending_manifest_file_number_); std::string descriptor_fname = DescriptorFileName(dbname_, pending_manifest_file_number_); std::unique_ptr descriptor_file; io_s = NewWritableFile(fs_.get(), descriptor_fname, &descriptor_file, opt_file_opts); if (io_s.ok()) { descriptor_file->SetPreallocationBlockSize( db_options_->manifest_preallocation_size); FileTypeSet tmp_set = db_options_->checksum_handoff_file_types; std::unique_ptr file_writer(new WritableFileWriter( std::move(descriptor_file), descriptor_fname, opt_file_opts, clock_, io_tracer_, nullptr, db_options_->listeners, nullptr, tmp_set.Contains(FileType::kDescriptorFile))); descriptor_log_.reset( new log::Writer(std::move(file_writer), 0, false)); s = WriteCurrentStateToManifest(curr_state, wal_additions, descriptor_log_.get(), io_s); } else { s = io_s; } } if (s.ok()) { if (!first_writer.edit_list.front()->IsColumnFamilyManipulation()) { for (int i = 0; i < static_cast(versions.size()); ++i) { versions[i]->PrepareApply(*mutable_cf_options_ptrs[i], true); } } // Write new records to MANIFEST log #ifndef NDEBUG size_t idx = 0; #endif for (auto& e : batch_edits) { std::string record; if (!e->EncodeTo(&record)) { s = Status::Corruption("Unable to encode VersionEdit:" + e->DebugString(true)); break; } TEST_KILL_RANDOM("VersionSet::LogAndApply:BeforeAddRecord", rocksdb_kill_odds * REDUCE_ODDS2); #ifndef NDEBUG if (batch_edits.size() > 1 && batch_edits.size() - 1 == idx) { TEST_SYNC_POINT_CALLBACK( "VersionSet::ProcessManifestWrites:BeforeWriteLastVersionEdit:0", nullptr); TEST_SYNC_POINT( "VersionSet::ProcessManifestWrites:BeforeWriteLastVersionEdit:1"); } ++idx; #endif /* !NDEBUG */ io_s = descriptor_log_->AddRecord(record); if (!io_s.ok()) { s = io_s; break; } } if (s.ok()) { io_s = SyncManifest(clock_, db_options_, descriptor_log_->file()); TEST_SYNC_POINT_CALLBACK( "VersionSet::ProcessManifestWrites:AfterSyncManifest", &io_s); } if (!io_s.ok()) { s = io_s; ROCKS_LOG_ERROR(db_options_->info_log, "MANIFEST write %s\n", s.ToString().c_str()); } } // If we just created a new descriptor file, install it by writing a // new CURRENT file that points to it. if (s.ok() && new_descriptor_log) { io_s = SetCurrentFile(fs_.get(), dbname_, pending_manifest_file_number_, db_directory); if (!io_s.ok()) { s = io_s; } TEST_SYNC_POINT("VersionSet::ProcessManifestWrites:AfterNewManifest"); } if (s.ok()) { // find offset in manifest file where this version is stored. new_manifest_file_size = descriptor_log_->file()->GetFileSize(); } if (first_writer.edit_list.front()->is_column_family_drop_) { TEST_SYNC_POINT("VersionSet::LogAndApply::ColumnFamilyDrop:0"); TEST_SYNC_POINT("VersionSet::LogAndApply::ColumnFamilyDrop:1"); TEST_SYNC_POINT("VersionSet::LogAndApply::ColumnFamilyDrop:2"); } LogFlush(db_options_->info_log); TEST_SYNC_POINT("VersionSet::LogAndApply:WriteManifestDone"); mu->Lock(); } if (s.ok()) { // Apply WAL edits, DB mutex must be held. for (auto& e : batch_edits) { if (e->IsWalAddition()) { s = wals_.AddWals(e->GetWalAdditions()); } else if (e->IsWalDeletion()) { s = wals_.DeleteWalsBefore(e->GetWalDeletion().GetLogNumber()); } if (!s.ok()) { break; } } } if (!io_s.ok()) { if (io_status_.ok()) { io_status_ = io_s; } } else if (!io_status_.ok()) { io_status_ = io_s; } // Append the old manifest file to the obsolete_manifest_ list to be deleted // by PurgeObsoleteFiles later. if (s.ok() && new_descriptor_log) { obsolete_manifests_.emplace_back( DescriptorFileName("", manifest_file_number_)); } // Install the new versions if (s.ok()) { if (first_writer.edit_list.front()->is_column_family_add_) { assert(batch_edits.size() == 1); assert(new_cf_options != nullptr); CreateColumnFamily(*new_cf_options, first_writer.edit_list.front()); } else if (first_writer.edit_list.front()->is_column_family_drop_) { assert(batch_edits.size() == 1); first_writer.cfd->SetDropped(); first_writer.cfd->UnrefAndTryDelete(); } else { // Each version in versions corresponds to a column family. // For each column family, update its log number indicating that logs // with number smaller than this should be ignored. uint64_t last_min_log_number_to_keep = 0; for (const auto& e : batch_edits) { ColumnFamilyData* cfd = nullptr; if (!e->IsColumnFamilyManipulation()) { cfd = column_family_set_->GetColumnFamily(e->column_family_); // e would not have been added to batch_edits if its corresponding // column family is dropped. assert(cfd); } if (cfd) { if (e->has_log_number_ && e->log_number_ > cfd->GetLogNumber()) { cfd->SetLogNumber(e->log_number_); } if (e->HasFullHistoryTsLow()) { cfd->SetFullHistoryTsLow(e->GetFullHistoryTsLow()); } } if (e->has_min_log_number_to_keep_) { last_min_log_number_to_keep = std::max(last_min_log_number_to_keep, e->min_log_number_to_keep_); } } if (last_min_log_number_to_keep != 0) { // Should only be set in 2PC mode. MarkMinLogNumberToKeep2PC(last_min_log_number_to_keep); } for (int i = 0; i < static_cast(versions.size()); ++i) { ColumnFamilyData* cfd = versions[i]->cfd_; AppendVersion(cfd, versions[i]); } } manifest_file_number_ = pending_manifest_file_number_; manifest_file_size_ = new_manifest_file_size; prev_log_number_ = first_writer.edit_list.front()->prev_log_number_; } else { std::string version_edits; for (auto& e : batch_edits) { version_edits += ("\n" + e->DebugString(true)); } ROCKS_LOG_ERROR(db_options_->info_log, "Error in committing version edit to MANIFEST: %s", version_edits.c_str()); for (auto v : versions) { delete v; } // If manifest append failed for whatever reason, the file could be // corrupted. So we need to force the next version update to start a // new manifest file. descriptor_log_.reset(); if (new_descriptor_log) { ROCKS_LOG_INFO(db_options_->info_log, "Deleting manifest %" PRIu64 " current manifest %" PRIu64 "\n", pending_manifest_file_number_, manifest_file_number_); Status manifest_del_status = env_->DeleteFile( DescriptorFileName(dbname_, pending_manifest_file_number_)); if (!manifest_del_status.ok()) { ROCKS_LOG_WARN(db_options_->info_log, "Failed to delete manifest %" PRIu64 ": %s", pending_manifest_file_number_, manifest_del_status.ToString().c_str()); } } } pending_manifest_file_number_ = 0; // wake up all the waiting writers while (true) { ManifestWriter* ready = manifest_writers_.front(); manifest_writers_.pop_front(); bool need_signal = true; for (const auto& w : writers) { if (&w == ready) { need_signal = false; break; } } ready->status = s; ready->done = true; if (ready->manifest_write_callback) { (ready->manifest_write_callback)(s); } if (need_signal) { ready->cv.Signal(); } if (ready == last_writer) { break; } } if (!manifest_writers_.empty()) { manifest_writers_.front()->cv.Signal(); } return s; } // 'datas' is gramatically incorrect. We still use this notation to indicate // that this variable represents a collection of column_family_data. Status VersionSet::LogAndApply( const autovector& column_family_datas, const autovector& mutable_cf_options_list, const autovector>& edit_lists, InstrumentedMutex* mu, FSDirectory* db_directory, bool new_descriptor_log, const ColumnFamilyOptions* new_cf_options, const std::vector>& manifest_wcbs) { mu->AssertHeld(); int num_edits = 0; for (const auto& elist : edit_lists) { num_edits += static_cast(elist.size()); } if (num_edits == 0) { return Status::OK(); } else if (num_edits > 1) { #ifndef NDEBUG for (const auto& edit_list : edit_lists) { for (const auto& edit : edit_list) { assert(!edit->IsColumnFamilyManipulation()); } } #endif /* ! NDEBUG */ } int num_cfds = static_cast(column_family_datas.size()); if (num_cfds == 1 && column_family_datas[0] == nullptr) { assert(edit_lists.size() == 1 && edit_lists[0].size() == 1); assert(edit_lists[0][0]->is_column_family_add_); assert(new_cf_options != nullptr); } std::deque writers; if (num_cfds > 0) { assert(static_cast(num_cfds) == mutable_cf_options_list.size()); assert(static_cast(num_cfds) == edit_lists.size()); } for (int i = 0; i < num_cfds; ++i) { const auto wcb = manifest_wcbs.empty() ? [](const Status&) {} : manifest_wcbs[i]; writers.emplace_back(mu, column_family_datas[i], *mutable_cf_options_list[i], edit_lists[i], wcb); manifest_writers_.push_back(&writers[i]); } assert(!writers.empty()); ManifestWriter& first_writer = writers.front(); TEST_SYNC_POINT_CALLBACK("VersionSet::LogAndApply:BeforeWriterWaiting", nullptr); while (!first_writer.done && &first_writer != manifest_writers_.front()) { first_writer.cv.Wait(); } if (first_writer.done) { // All non-CF-manipulation operations can be grouped together and committed // to MANIFEST. They should all have finished. The status code is stored in // the first manifest writer. #ifndef NDEBUG for (const auto& writer : writers) { assert(writer.done); } TEST_SYNC_POINT_CALLBACK("VersionSet::LogAndApply:WakeUpAndDone", mu); #endif /* !NDEBUG */ return first_writer.status; } int num_undropped_cfds = 0; for (auto cfd : column_family_datas) { // if cfd == nullptr, it is a column family add. if (cfd == nullptr || !cfd->IsDropped()) { ++num_undropped_cfds; } } if (0 == num_undropped_cfds) { for (int i = 0; i != num_cfds; ++i) { manifest_writers_.pop_front(); } // Notify new head of manifest write queue. if (!manifest_writers_.empty()) { manifest_writers_.front()->cv.Signal(); } return Status::ColumnFamilyDropped(); } return ProcessManifestWrites(writers, mu, db_directory, new_descriptor_log, new_cf_options); } void VersionSet::LogAndApplyCFHelper(VersionEdit* edit) { assert(edit->IsColumnFamilyManipulation()); edit->SetNextFile(next_file_number_.load()); // The log might have data that is not visible to memtbale and hence have not // updated the last_sequence_ yet. It is also possible that the log has is // expecting some new data that is not written yet. Since LastSequence is an // upper bound on the sequence, it is ok to record // last_allocated_sequence_ as the last sequence. edit->SetLastSequence(db_options_->two_write_queues ? last_allocated_sequence_ : last_sequence_); if (edit->is_column_family_drop_) { // if we drop column family, we have to make sure to save max column family, // so that we don't reuse existing ID edit->SetMaxColumnFamily(column_family_set_->GetMaxColumnFamily()); } } Status VersionSet::LogAndApplyHelper(ColumnFamilyData* cfd, VersionBuilder* builder, VersionEdit* edit, InstrumentedMutex* mu) { #ifdef NDEBUG (void)cfd; #endif mu->AssertHeld(); assert(!edit->IsColumnFamilyManipulation()); if (edit->has_log_number_) { assert(edit->log_number_ >= cfd->GetLogNumber()); assert(edit->log_number_ < next_file_number_.load()); } if (!edit->has_prev_log_number_) { edit->SetPrevLogNumber(prev_log_number_); } edit->SetNextFile(next_file_number_.load()); // The log might have data that is not visible to memtbale and hence have not // updated the last_sequence_ yet. It is also possible that the log has is // expecting some new data that is not written yet. Since LastSequence is an // upper bound on the sequence, it is ok to record // last_allocated_sequence_ as the last sequence. edit->SetLastSequence(db_options_->two_write_queues ? last_allocated_sequence_ : last_sequence_); // The builder can be nullptr only if edit is WAL manipulation, // because WAL edits do not need to be applied to versions, // we return Status::OK() in this case. assert(builder || edit->IsWalManipulation()); return builder ? builder->Apply(edit) : Status::OK(); } Status VersionSet::ApplyOneVersionEditToBuilder( VersionEdit& edit, const std::unordered_map& name_to_options, std::unordered_map& column_families_not_found, std::unordered_map>& builders, VersionEditParams* version_edit_params) { // Not found means that user didn't supply that column // family option AND we encountered column family add // record. Once we encounter column family drop record, // we will delete the column family from // column_families_not_found. bool cf_in_not_found = (column_families_not_found.find(edit.column_family_) != column_families_not_found.end()); // in builders means that user supplied that column family // option AND that we encountered column family add record bool cf_in_builders = builders.find(edit.column_family_) != builders.end(); // they can't both be true assert(!(cf_in_not_found && cf_in_builders)); ColumnFamilyData* cfd = nullptr; if (edit.is_column_family_add_) { if (cf_in_builders || cf_in_not_found) { return Status::Corruption( "Manifest adding the same column family twice: " + edit.column_family_name_); } auto cf_options = name_to_options.find(edit.column_family_name_); // implicitly add persistent_stats column family without requiring user // to specify bool is_persistent_stats_column_family = edit.column_family_name_.compare(kPersistentStatsColumnFamilyName) == 0; if (cf_options == name_to_options.end() && !is_persistent_stats_column_family) { column_families_not_found.insert( {edit.column_family_, edit.column_family_name_}); } else { // recover persistent_stats CF from a DB that already contains it if (is_persistent_stats_column_family) { ColumnFamilyOptions cfo; OptimizeForPersistentStats(&cfo); cfd = CreateColumnFamily(cfo, &edit); } else { cfd = CreateColumnFamily(cf_options->second, &edit); } cfd->set_initialized(); builders.insert(std::make_pair( edit.column_family_, std::unique_ptr( new BaseReferencedVersionBuilder(cfd)))); } } else if (edit.is_column_family_drop_) { if (cf_in_builders) { auto builder = builders.find(edit.column_family_); assert(builder != builders.end()); builders.erase(builder); cfd = column_family_set_->GetColumnFamily(edit.column_family_); assert(cfd != nullptr); if (cfd->UnrefAndTryDelete()) { cfd = nullptr; } else { // who else can have reference to cfd!? assert(false); } } else if (cf_in_not_found) { column_families_not_found.erase(edit.column_family_); } else { return Status::Corruption( "Manifest - dropping non-existing column family"); } } else if (edit.IsWalAddition()) { Status s = wals_.AddWals(edit.GetWalAdditions()); if (!s.ok()) { return s; } } else if (edit.IsWalDeletion()) { Status s = wals_.DeleteWalsBefore(edit.GetWalDeletion().GetLogNumber()); if (!s.ok()) { return s; } } else if (!cf_in_not_found) { if (!cf_in_builders) { return Status::Corruption( "Manifest record referencing unknown column family"); } cfd = column_family_set_->GetColumnFamily(edit.column_family_); // this should never happen since cf_in_builders is true assert(cfd != nullptr); // if it is not column family add or column family drop, // then it's a file add/delete, which should be forwarded // to builder auto builder = builders.find(edit.column_family_); assert(builder != builders.end()); Status s = builder->second->version_builder()->Apply(&edit); if (!s.ok()) { return s; } } return ExtractInfoFromVersionEdit(cfd, edit, version_edit_params); } Status VersionSet::ExtractInfoFromVersionEdit( ColumnFamilyData* cfd, const VersionEdit& from_edit, VersionEditParams* version_edit_params) { if (cfd != nullptr) { if (from_edit.has_db_id_) { version_edit_params->SetDBId(from_edit.db_id_); } if (from_edit.has_log_number_) { if (cfd->GetLogNumber() > from_edit.log_number_) { ROCKS_LOG_WARN( db_options_->info_log, "MANIFEST corruption detected, but ignored - Log numbers in " "records NOT monotonically increasing"); } else { cfd->SetLogNumber(from_edit.log_number_); version_edit_params->SetLogNumber(from_edit.log_number_); } } if (from_edit.has_comparator_ && from_edit.comparator_ != cfd->user_comparator()->Name()) { return Status::InvalidArgument( cfd->user_comparator()->Name(), "does not match existing comparator " + from_edit.comparator_); } if (from_edit.HasFullHistoryTsLow()) { const std::string& new_ts = from_edit.GetFullHistoryTsLow(); cfd->SetFullHistoryTsLow(new_ts); } } if (from_edit.has_prev_log_number_) { version_edit_params->SetPrevLogNumber(from_edit.prev_log_number_); } if (from_edit.has_next_file_number_) { version_edit_params->SetNextFile(from_edit.next_file_number_); } if (from_edit.has_max_column_family_) { version_edit_params->SetMaxColumnFamily(from_edit.max_column_family_); } if (from_edit.has_min_log_number_to_keep_) { version_edit_params->min_log_number_to_keep_ = std::max(version_edit_params->min_log_number_to_keep_, from_edit.min_log_number_to_keep_); } if (from_edit.has_last_sequence_) { version_edit_params->SetLastSequence(from_edit.last_sequence_); } return Status::OK(); } Status VersionSet::GetCurrentManifestPath(const std::string& dbname, FileSystem* fs, std::string* manifest_path, uint64_t* manifest_file_number) { assert(fs != nullptr); assert(manifest_path != nullptr); assert(manifest_file_number != nullptr); std::string fname; Status s = ReadFileToString(fs, CurrentFileName(dbname), &fname); if (!s.ok()) { return s; } if (fname.empty() || fname.back() != '\n') { return Status::Corruption("CURRENT file does not end with newline"); } // remove the trailing '\n' fname.resize(fname.size() - 1); FileType type; bool parse_ok = ParseFileName(fname, manifest_file_number, &type); if (!parse_ok || type != kDescriptorFile) { return Status::Corruption("CURRENT file corrupted"); } *manifest_path = dbname; if (dbname.back() != '/') { manifest_path->push_back('/'); } manifest_path->append(fname); return Status::OK(); } Status VersionSet::ReadAndRecover( log::Reader& reader, AtomicGroupReadBuffer* read_buffer, const std::unordered_map& name_to_options, std::unordered_map& column_families_not_found, std::unordered_map>& builders, Status* log_read_status, VersionEditParams* version_edit_params, std::string* db_id) { assert(read_buffer != nullptr); assert(log_read_status != nullptr); Status s; Slice record; std::string scratch; size_t recovered_edits = 0; while (s.ok() && reader.ReadRecord(&record, &scratch) && log_read_status->ok()) { VersionEdit edit; s = edit.DecodeFrom(record); if (!s.ok()) { break; } if (edit.has_db_id_) { db_id_ = edit.GetDbId(); if (db_id != nullptr) { db_id->assign(edit.GetDbId()); } } s = read_buffer->AddEdit(&edit); if (!s.ok()) { break; } if (edit.is_in_atomic_group_) { if (read_buffer->IsFull()) { // Apply edits in an atomic group when we have read all edits in the // group. for (auto& e : read_buffer->replay_buffer()) { s = ApplyOneVersionEditToBuilder(e, name_to_options, column_families_not_found, builders, version_edit_params); if (!s.ok()) { break; } recovered_edits++; } if (!s.ok()) { break; } read_buffer->Clear(); } } else { // Apply a normal edit immediately. s = ApplyOneVersionEditToBuilder(edit, name_to_options, column_families_not_found, builders, version_edit_params); if (s.ok()) { recovered_edits++; } } } if (!log_read_status->ok()) { s = *log_read_status; } if (!s.ok()) { // Clear the buffer if we fail to decode/apply an edit. read_buffer->Clear(); } TEST_SYNC_POINT_CALLBACK("VersionSet::ReadAndRecover:RecoveredEdits", &recovered_edits); return s; } Status VersionSet::Recover( const std::vector& column_families, bool read_only, std::string* db_id) { // Read "CURRENT" file, which contains a pointer to the current manifest file std::string manifest_path; Status s = GetCurrentManifestPath(dbname_, fs_.get(), &manifest_path, &manifest_file_number_); if (!s.ok()) { return s; } ROCKS_LOG_INFO(db_options_->info_log, "Recovering from manifest file: %s\n", manifest_path.c_str()); std::unique_ptr manifest_file_reader; { std::unique_ptr manifest_file; s = fs_->NewSequentialFile(manifest_path, fs_->OptimizeForManifestRead(file_options_), &manifest_file, nullptr); if (!s.ok()) { return s; } manifest_file_reader.reset( new SequentialFileReader(std::move(manifest_file), manifest_path, db_options_->log_readahead_size, io_tracer_)); } uint64_t current_manifest_file_size = 0; uint64_t log_number = 0; { VersionSet::LogReporter reporter; Status log_read_status; reporter.status = &log_read_status; log::Reader reader(nullptr, std::move(manifest_file_reader), &reporter, true /* checksum */, 0 /* log_number */); VersionEditHandler handler( read_only, column_families, const_cast(this), /*track_missing_files=*/false, /*no_error_if_table_files_missing=*/false, io_tracer_); handler.Iterate(reader, &log_read_status); s = handler.status(); if (s.ok()) { log_number = handler.GetVersionEditParams().log_number_; current_manifest_file_size = reader.GetReadOffset(); assert(current_manifest_file_size != 0); handler.GetDbId(db_id); } } if (s.ok()) { manifest_file_size_ = current_manifest_file_size; ROCKS_LOG_INFO( db_options_->info_log, "Recovered from manifest file:%s succeeded," "manifest_file_number is %" PRIu64 ", next_file_number is %" PRIu64 ", last_sequence is %" PRIu64 ", log_number is %" PRIu64 ",prev_log_number is %" PRIu64 ",max_column_family is %" PRIu32 ",min_log_number_to_keep is %" PRIu64 "\n", manifest_path.c_str(), manifest_file_number_, next_file_number_.load(), last_sequence_.load(), log_number, prev_log_number_, column_family_set_->GetMaxColumnFamily(), min_log_number_to_keep_2pc()); for (auto cfd : *column_family_set_) { if (cfd->IsDropped()) { continue; } ROCKS_LOG_INFO(db_options_->info_log, "Column family [%s] (ID %" PRIu32 "), log number is %" PRIu64 "\n", cfd->GetName().c_str(), cfd->GetID(), cfd->GetLogNumber()); } } return s; } namespace { class ManifestPicker { public: explicit ManifestPicker(const std::string& dbname, const std::vector& files_in_dbname); // REQUIRES Valid() == true std::string GetNextManifest(uint64_t* file_number, std::string* file_name); bool Valid() const { return manifest_file_iter_ != manifest_files_.end(); } private: const std::string& dbname_; // MANIFEST file names(s) std::vector manifest_files_; std::vector::const_iterator manifest_file_iter_; }; ManifestPicker::ManifestPicker(const std::string& dbname, const std::vector& files_in_dbname) : dbname_(dbname) { // populate manifest files assert(!files_in_dbname.empty()); for (const auto& fname : files_in_dbname) { uint64_t file_num = 0; FileType file_type; bool parse_ok = ParseFileName(fname, &file_num, &file_type); if (parse_ok && file_type == kDescriptorFile) { manifest_files_.push_back(fname); } } // seek to first manifest std::sort(manifest_files_.begin(), manifest_files_.end(), [](const std::string& lhs, const std::string& rhs) { uint64_t num1 = 0; uint64_t num2 = 0; FileType type1; FileType type2; bool parse_ok1 = ParseFileName(lhs, &num1, &type1); bool parse_ok2 = ParseFileName(rhs, &num2, &type2); #ifndef NDEBUG assert(parse_ok1); assert(parse_ok2); #else (void)parse_ok1; (void)parse_ok2; #endif return num1 > num2; }); manifest_file_iter_ = manifest_files_.begin(); } std::string ManifestPicker::GetNextManifest(uint64_t* number, std::string* file_name) { assert(Valid()); std::string ret; if (manifest_file_iter_ != manifest_files_.end()) { ret.assign(dbname_); if (ret.back() != kFilePathSeparator) { ret.push_back(kFilePathSeparator); } ret.append(*manifest_file_iter_); if (number) { FileType type; bool parse = ParseFileName(*manifest_file_iter_, number, &type); assert(type == kDescriptorFile); #ifndef NDEBUG assert(parse); #else (void)parse; #endif } if (file_name) { *file_name = *manifest_file_iter_; } ++manifest_file_iter_; } return ret; } } // namespace Status VersionSet::TryRecover( const std::vector& column_families, bool read_only, const std::vector& files_in_dbname, std::string* db_id, bool* has_missing_table_file) { ManifestPicker manifest_picker(dbname_, files_in_dbname); if (!manifest_picker.Valid()) { return Status::Corruption("Cannot locate MANIFEST file in " + dbname_); } Status s; std::string manifest_path = manifest_picker.GetNextManifest(&manifest_file_number_, nullptr); while (!manifest_path.empty()) { s = TryRecoverFromOneManifest(manifest_path, column_families, read_only, db_id, has_missing_table_file); if (s.ok() || !manifest_picker.Valid()) { break; } Reset(); manifest_path = manifest_picker.GetNextManifest(&manifest_file_number_, nullptr); } return s; } Status VersionSet::TryRecoverFromOneManifest( const std::string& manifest_path, const std::vector& column_families, bool read_only, std::string* db_id, bool* has_missing_table_file) { ROCKS_LOG_INFO(db_options_->info_log, "Trying to recover from manifest: %s\n", manifest_path.c_str()); std::unique_ptr manifest_file_reader; Status s; { std::unique_ptr manifest_file; s = fs_->NewSequentialFile(manifest_path, fs_->OptimizeForManifestRead(file_options_), &manifest_file, nullptr); if (!s.ok()) { return s; } manifest_file_reader.reset( new SequentialFileReader(std::move(manifest_file), manifest_path, db_options_->log_readahead_size, io_tracer_)); } assert(s.ok()); VersionSet::LogReporter reporter; reporter.status = &s; log::Reader reader(nullptr, std::move(manifest_file_reader), &reporter, /*checksum=*/true, /*log_num=*/0); VersionEditHandlerPointInTime handler_pit( read_only, column_families, const_cast(this), io_tracer_); handler_pit.Iterate(reader, &s); handler_pit.GetDbId(db_id); assert(nullptr != has_missing_table_file); *has_missing_table_file = handler_pit.HasMissingFiles(); return handler_pit.status(); } Status VersionSet::ListColumnFamilies(std::vector* column_families, const std::string& dbname, FileSystem* fs) { // these are just for performance reasons, not correcntes, // so we're fine using the defaults FileOptions soptions; // Read "CURRENT" file, which contains a pointer to the current manifest file std::string manifest_path; uint64_t manifest_file_number; Status s = GetCurrentManifestPath(dbname, fs, &manifest_path, &manifest_file_number); if (!s.ok()) { return s; } std::unique_ptr file_reader; { std::unique_ptr file; s = fs->NewSequentialFile(manifest_path, soptions, &file, nullptr); if (!s.ok()) { return s; } file_reader.reset(new SequentialFileReader(std::move(file), manifest_path, nullptr /*IOTracer*/)); } VersionSet::LogReporter reporter; reporter.status = &s; log::Reader reader(nullptr, std::move(file_reader), &reporter, true /* checksum */, 0 /* log_number */); ListColumnFamiliesHandler handler; handler.Iterate(reader, &s); assert(column_families); column_families->clear(); if (handler.status().ok()) { for (const auto& iter : handler.GetColumnFamilyNames()) { column_families->push_back(iter.second); } } return handler.status(); } #ifndef ROCKSDB_LITE Status VersionSet::ReduceNumberOfLevels(const std::string& dbname, const Options* options, const FileOptions& file_options, int new_levels) { if (new_levels <= 1) { return Status::InvalidArgument( "Number of levels needs to be bigger than 1"); } ImmutableDBOptions db_options(*options); ColumnFamilyOptions cf_options(*options); std::shared_ptr tc(NewLRUCache(options->max_open_files - 10, options->table_cache_numshardbits)); WriteController wc(options->delayed_write_rate); WriteBufferManager wb(options->db_write_buffer_size); VersionSet versions(dbname, &db_options, file_options, tc.get(), &wb, &wc, nullptr /*BlockCacheTracer*/, nullptr /*IOTracer*/); Status status; std::vector dummy; ColumnFamilyDescriptor dummy_descriptor(kDefaultColumnFamilyName, ColumnFamilyOptions(*options)); dummy.push_back(dummy_descriptor); status = versions.Recover(dummy); if (!status.ok()) { return status; } Version* current_version = versions.GetColumnFamilySet()->GetDefault()->current(); auto* vstorage = current_version->storage_info(); int current_levels = vstorage->num_levels(); if (current_levels <= new_levels) { return Status::OK(); } // Make sure there are file only on one level from // (new_levels-1) to (current_levels-1) int first_nonempty_level = -1; int first_nonempty_level_filenum = 0; for (int i = new_levels - 1; i < current_levels; i++) { int file_num = vstorage->NumLevelFiles(i); if (file_num != 0) { if (first_nonempty_level < 0) { first_nonempty_level = i; first_nonempty_level_filenum = file_num; } else { char msg[255]; snprintf(msg, sizeof(msg), "Found at least two levels containing files: " "[%d:%d],[%d:%d].\n", first_nonempty_level, first_nonempty_level_filenum, i, file_num); return Status::InvalidArgument(msg); } } } // we need to allocate an array with the old number of levels size to // avoid SIGSEGV in WriteCurrentStatetoManifest() // however, all levels bigger or equal to new_levels will be empty std::vector* new_files_list = new std::vector[current_levels]; for (int i = 0; i < new_levels - 1; i++) { new_files_list[i] = vstorage->LevelFiles(i); } if (first_nonempty_level > 0) { auto& new_last_level = new_files_list[new_levels - 1]; new_last_level = vstorage->LevelFiles(first_nonempty_level); for (size_t i = 0; i < new_last_level.size(); ++i) { const FileMetaData* const meta = new_last_level[i]; assert(meta); const uint64_t file_number = meta->fd.GetNumber(); vstorage->file_locations_[file_number] = VersionStorageInfo::FileLocation(new_levels - 1, i); } } delete[] vstorage -> files_; vstorage->files_ = new_files_list; vstorage->num_levels_ = new_levels; MutableCFOptions mutable_cf_options(*options); VersionEdit ve; InstrumentedMutex dummy_mutex; InstrumentedMutexLock l(&dummy_mutex); return versions.LogAndApply( versions.GetColumnFamilySet()->GetDefault(), mutable_cf_options, &ve, &dummy_mutex, nullptr, true); } // Get the checksum information including the checksum and checksum function // name of all SST files in VersionSet. Store the information in // FileChecksumList which contains a map from file number to its checksum info. // If DB is not running, make sure call VersionSet::Recover() to load the file // metadata from Manifest to VersionSet before calling this function. Status VersionSet::GetLiveFilesChecksumInfo(FileChecksumList* checksum_list) { // Clean the previously stored checksum information if any. Status s; if (checksum_list == nullptr) { s = Status::InvalidArgument("checksum_list is nullptr"); return s; } checksum_list->reset(); for (auto cfd : *column_family_set_) { if (cfd->IsDropped() || !cfd->initialized()) { continue; } for (int level = 0; level < cfd->NumberLevels(); level++) { for (const auto& file : cfd->current()->storage_info()->LevelFiles(level)) { s = checksum_list->InsertOneFileChecksum(file->fd.GetNumber(), file->file_checksum, file->file_checksum_func_name); if (!s.ok()) { break; } } if (!s.ok()) { break; } } if (!s.ok()) { break; } } return s; } Status VersionSet::DumpManifest(Options& options, std::string& dscname, bool verbose, bool hex, bool json) { // Open the specified manifest file. std::unique_ptr file_reader; Status s; { std::unique_ptr file; const std::shared_ptr& fs = options.env->GetFileSystem(); s = fs->NewSequentialFile( dscname, fs->OptimizeForManifestRead(file_options_), &file, nullptr); if (!s.ok()) { return s; } file_reader.reset(new SequentialFileReader( std::move(file), dscname, db_options_->log_readahead_size, io_tracer_)); } std::vector column_families( 1, ColumnFamilyDescriptor(kDefaultColumnFamilyName, options)); DumpManifestHandler handler(column_families, this, io_tracer_, verbose, hex, json); { VersionSet::LogReporter reporter; reporter.status = &s; log::Reader reader(nullptr, std::move(file_reader), &reporter, true /* checksum */, 0 /* log_number */); handler.Iterate(reader, &s); } return handler.status(); } #endif // ROCKSDB_LITE void VersionSet::MarkFileNumberUsed(uint64_t number) { // only called during recovery and repair which are single threaded, so this // works because there can't be concurrent calls if (next_file_number_.load(std::memory_order_relaxed) <= number) { next_file_number_.store(number + 1, std::memory_order_relaxed); } } // Called only either from ::LogAndApply which is protected by mutex or during // recovery which is single-threaded. void VersionSet::MarkMinLogNumberToKeep2PC(uint64_t number) { if (min_log_number_to_keep_2pc_.load(std::memory_order_relaxed) < number) { min_log_number_to_keep_2pc_.store(number, std::memory_order_relaxed); } } Status VersionSet::WriteCurrentStateToManifest( const std::unordered_map& curr_state, const VersionEdit& wal_additions, log::Writer* log, IOStatus& io_s) { // TODO: Break up into multiple records to reduce memory usage on recovery? // WARNING: This method doesn't hold a mutex!! // This is done without DB mutex lock held, but only within single-threaded // LogAndApply. Column family manipulations can only happen within LogAndApply // (the same single thread), so we're safe to iterate. assert(io_s.ok()); if (db_options_->write_dbid_to_manifest) { VersionEdit edit_for_db_id; assert(!db_id_.empty()); edit_for_db_id.SetDBId(db_id_); std::string db_id_record; if (!edit_for_db_id.EncodeTo(&db_id_record)) { return Status::Corruption("Unable to Encode VersionEdit:" + edit_for_db_id.DebugString(true)); } io_s = log->AddRecord(db_id_record); if (!io_s.ok()) { return io_s; } } // Save WALs. if (!wal_additions.GetWalAdditions().empty()) { TEST_SYNC_POINT_CALLBACK("VersionSet::WriteCurrentStateToManifest:SaveWal", const_cast(&wal_additions)); std::string record; if (!wal_additions.EncodeTo(&record)) { return Status::Corruption("Unable to Encode VersionEdit: " + wal_additions.DebugString(true)); } io_s = log->AddRecord(record); if (!io_s.ok()) { return io_s; } } for (auto cfd : *column_family_set_) { assert(cfd); if (cfd->IsDropped()) { continue; } assert(cfd->initialized()); { // Store column family info VersionEdit edit; if (cfd->GetID() != 0) { // default column family is always there, // no need to explicitly write it edit.AddColumnFamily(cfd->GetName()); edit.SetColumnFamily(cfd->GetID()); } edit.SetComparatorName( cfd->internal_comparator().user_comparator()->Name()); std::string record; if (!edit.EncodeTo(&record)) { return Status::Corruption( "Unable to Encode VersionEdit:" + edit.DebugString(true)); } io_s = log->AddRecord(record); if (!io_s.ok()) { return io_s; } } { // Save files VersionEdit edit; edit.SetColumnFamily(cfd->GetID()); assert(cfd->current()); assert(cfd->current()->storage_info()); for (int level = 0; level < cfd->NumberLevels(); level++) { for (const auto& f : cfd->current()->storage_info()->LevelFiles(level)) { edit.AddFile(level, f->fd.GetNumber(), f->fd.GetPathId(), f->fd.GetFileSize(), f->smallest, f->largest, f->fd.smallest_seqno, f->fd.largest_seqno, f->marked_for_compaction, f->oldest_blob_file_number, f->oldest_ancester_time, f->file_creation_time, f->file_checksum, f->file_checksum_func_name); } } const auto& blob_files = cfd->current()->storage_info()->GetBlobFiles(); for (const auto& pair : blob_files) { const uint64_t blob_file_number = pair.first; const auto& meta = pair.second; assert(meta); assert(blob_file_number == meta->GetBlobFileNumber()); edit.AddBlobFile(blob_file_number, meta->GetTotalBlobCount(), meta->GetTotalBlobBytes(), meta->GetChecksumMethod(), meta->GetChecksumValue()); if (meta->GetGarbageBlobCount() > 0) { edit.AddBlobFileGarbage(blob_file_number, meta->GetGarbageBlobCount(), meta->GetGarbageBlobBytes()); } } const auto iter = curr_state.find(cfd->GetID()); assert(iter != curr_state.end()); uint64_t log_number = iter->second.log_number; edit.SetLogNumber(log_number); if (cfd->GetID() == 0) { // min_log_number_to_keep is for the whole db, not for specific column family. // So it does not need to be set for every column family, just need to be set once. // Since default CF can never be dropped, we set the min_log to the default CF here. uint64_t min_log = min_log_number_to_keep_2pc(); if (min_log != 0) { edit.SetMinLogNumberToKeep(min_log); } } const std::string& full_history_ts_low = iter->second.full_history_ts_low; if (!full_history_ts_low.empty()) { edit.SetFullHistoryTsLow(full_history_ts_low); } std::string record; if (!edit.EncodeTo(&record)) { return Status::Corruption( "Unable to Encode VersionEdit:" + edit.DebugString(true)); } io_s = log->AddRecord(record); if (!io_s.ok()) { return io_s; } } } return Status::OK(); } // TODO(aekmekji): in CompactionJob::GenSubcompactionBoundaries(), this // function is called repeatedly with consecutive pairs of slices. For example // if the slice list is [a, b, c, d] this function is called with arguments // (a,b) then (b,c) then (c,d). Knowing this, an optimization is possible where // we avoid doing binary search for the keys b and c twice and instead somehow // maintain state of where they first appear in the files. uint64_t VersionSet::ApproximateSize(const SizeApproximationOptions& options, Version* v, const Slice& start, const Slice& end, int start_level, int end_level, TableReaderCaller caller) { const auto& icmp = v->cfd_->internal_comparator(); // pre-condition assert(icmp.Compare(start, end) <= 0); uint64_t total_full_size = 0; const auto* vstorage = v->storage_info(); const int num_non_empty_levels = vstorage->num_non_empty_levels(); end_level = (end_level == -1) ? num_non_empty_levels : std::min(end_level, num_non_empty_levels); assert(start_level <= end_level); // Outline of the optimization that uses options.files_size_error_margin. // When approximating the files total size that is used to store a keys range, // we first sum up the sizes of the files that fully fall into the range. // Then we sum up the sizes of all the files that may intersect with the range // (this includes all files in L0 as well). Then, if total_intersecting_size // is smaller than total_full_size * options.files_size_error_margin - we can // infer that the intersecting files have a sufficiently negligible // contribution to the total size, and we can approximate the storage required // for the keys in range as just half of the intersecting_files_size. // E.g., if the value of files_size_error_margin is 0.1, then the error of the // approximation is limited to only ~10% of the total size of files that fully // fall into the keys range. In such case, this helps to avoid a costly // process of binary searching the intersecting files that is required only // for a more precise calculation of the total size. autovector first_files; autovector last_files; // scan all the levels for (int level = start_level; level < end_level; ++level) { const LevelFilesBrief& files_brief = vstorage->LevelFilesBrief(level); if (files_brief.num_files == 0) { // empty level, skip exploration continue; } if (level == 0) { // level 0 files are not in sorted order, we need to iterate through // the list to compute the total bytes that require scanning, // so handle the case explicitly (similarly to first_files case) for (size_t i = 0; i < files_brief.num_files; i++) { first_files.push_back(&files_brief.files[i]); } continue; } assert(level > 0); assert(files_brief.num_files > 0); // identify the file position for start key const int idx_start = FindFileInRange(icmp, files_brief, start, 0, static_cast(files_brief.num_files - 1)); assert(static_cast(idx_start) < files_brief.num_files); // identify the file position for end key int idx_end = idx_start; if (icmp.Compare(files_brief.files[idx_end].largest_key, end) < 0) { idx_end = FindFileInRange(icmp, files_brief, end, idx_start, static_cast(files_brief.num_files - 1)); } assert(idx_end >= idx_start && static_cast(idx_end) < files_brief.num_files); // scan all files from the starting index to the ending index // (inferred from the sorted order) // first scan all the intermediate full files (excluding first and last) for (int i = idx_start + 1; i < idx_end; ++i) { uint64_t file_size = files_brief.files[i].fd.GetFileSize(); // The entire file falls into the range, so we can just take its size. assert(file_size == ApproximateSize(v, files_brief.files[i], start, end, caller)); total_full_size += file_size; } // save the first and the last files (which may be the same file), so we // can scan them later. first_files.push_back(&files_brief.files[idx_start]); if (idx_start != idx_end) { // we need to estimate size for both files, only if they are different last_files.push_back(&files_brief.files[idx_end]); } } // The sum of all file sizes that intersect the [start, end] keys range. uint64_t total_intersecting_size = 0; for (const auto* file_ptr : first_files) { total_intersecting_size += file_ptr->fd.GetFileSize(); } for (const auto* file_ptr : last_files) { total_intersecting_size += file_ptr->fd.GetFileSize(); } // Now scan all the first & last files at each level, and estimate their size. // If the total_intersecting_size is less than X% of the total_full_size - we // want to approximate the result in order to avoid the costly binary search // inside ApproximateSize. We use half of file size as an approximation below. const double margin = options.files_size_error_margin; if (margin > 0 && total_intersecting_size < static_cast(total_full_size * margin)) { total_full_size += total_intersecting_size / 2; } else { // Estimate for all the first files (might also be last files), at each // level for (const auto file_ptr : first_files) { total_full_size += ApproximateSize(v, *file_ptr, start, end, caller); } // Estimate for all the last files, at each level for (const auto file_ptr : last_files) { // We could use ApproximateSize here, but calling ApproximateOffsetOf // directly is just more efficient. total_full_size += ApproximateOffsetOf(v, *file_ptr, end, caller); } } return total_full_size; } uint64_t VersionSet::ApproximateOffsetOf(Version* v, const FdWithKeyRange& f, const Slice& key, TableReaderCaller caller) { // pre-condition assert(v); const auto& icmp = v->cfd_->internal_comparator(); uint64_t result = 0; if (icmp.Compare(f.largest_key, key) <= 0) { // Entire file is before "key", so just add the file size result = f.fd.GetFileSize(); } else if (icmp.Compare(f.smallest_key, key) > 0) { // Entire file is after "key", so ignore result = 0; } else { // "key" falls in the range for this table. Add the // approximate offset of "key" within the table. TableCache* table_cache = v->cfd_->table_cache(); if (table_cache != nullptr) { result = table_cache->ApproximateOffsetOf( key, f.file_metadata->fd, caller, icmp, v->GetMutableCFOptions().prefix_extractor.get()); } } return result; } uint64_t VersionSet::ApproximateSize(Version* v, const FdWithKeyRange& f, const Slice& start, const Slice& end, TableReaderCaller caller) { // pre-condition assert(v); const auto& icmp = v->cfd_->internal_comparator(); assert(icmp.Compare(start, end) <= 0); if (icmp.Compare(f.largest_key, start) <= 0 || icmp.Compare(f.smallest_key, end) > 0) { // Entire file is before or after the start/end keys range return 0; } if (icmp.Compare(f.smallest_key, start) >= 0) { // Start of the range is before the file start - approximate by end offset return ApproximateOffsetOf(v, f, end, caller); } if (icmp.Compare(f.largest_key, end) < 0) { // End of the range is after the file end - approximate by subtracting // start offset from the file size uint64_t start_offset = ApproximateOffsetOf(v, f, start, caller); assert(f.fd.GetFileSize() >= start_offset); return f.fd.GetFileSize() - start_offset; } // The interval falls entirely in the range for this file. TableCache* table_cache = v->cfd_->table_cache(); if (table_cache == nullptr) { return 0; } return table_cache->ApproximateSize( start, end, f.file_metadata->fd, caller, icmp, v->GetMutableCFOptions().prefix_extractor.get()); } void VersionSet::AddLiveFiles(std::vector* live_table_files, std::vector* live_blob_files) const { assert(live_table_files); assert(live_blob_files); // pre-calculate space requirement size_t total_table_files = 0; size_t total_blob_files = 0; assert(column_family_set_); for (auto cfd : *column_family_set_) { assert(cfd); if (!cfd->initialized()) { continue; } Version* const dummy_versions = cfd->dummy_versions(); assert(dummy_versions); for (Version* v = dummy_versions->next_; v != dummy_versions; v = v->next_) { assert(v); const auto* vstorage = v->storage_info(); assert(vstorage); for (int level = 0; level < vstorage->num_levels(); ++level) { total_table_files += vstorage->LevelFiles(level).size(); } total_blob_files += vstorage->GetBlobFiles().size(); } } // just one time extension to the right size live_table_files->reserve(live_table_files->size() + total_table_files); live_blob_files->reserve(live_blob_files->size() + total_blob_files); assert(column_family_set_); for (auto cfd : *column_family_set_) { assert(cfd); if (!cfd->initialized()) { continue; } auto* current = cfd->current(); bool found_current = false; Version* const dummy_versions = cfd->dummy_versions(); assert(dummy_versions); for (Version* v = dummy_versions->next_; v != dummy_versions; v = v->next_) { v->AddLiveFiles(live_table_files, live_blob_files); if (v == current) { found_current = true; } } if (!found_current && current != nullptr) { // Should never happen unless it is a bug. assert(false); current->AddLiveFiles(live_table_files, live_blob_files); } } } InternalIterator* VersionSet::MakeInputIterator( const ReadOptions& read_options, const Compaction* c, RangeDelAggregator* range_del_agg, const FileOptions& file_options_compactions) { auto cfd = c->column_family_data(); // Level-0 files have to be merged together. For other levels, // we will make a concatenating iterator per level. // TODO(opt): use concatenating iterator for level-0 if there is no overlap const size_t space = (c->level() == 0 ? c->input_levels(0)->num_files + c->num_input_levels() - 1 : c->num_input_levels()); InternalIterator** list = new InternalIterator* [space]; size_t num = 0; for (size_t which = 0; which < c->num_input_levels(); which++) { if (c->input_levels(which)->num_files != 0) { if (c->level(which) == 0) { const LevelFilesBrief* flevel = c->input_levels(which); for (size_t i = 0; i < flevel->num_files; i++) { list[num++] = cfd->table_cache()->NewIterator( read_options, file_options_compactions, cfd->internal_comparator(), *flevel->files[i].file_metadata, range_del_agg, c->mutable_cf_options()->prefix_extractor.get(), /*table_reader_ptr=*/nullptr, /*file_read_hist=*/nullptr, TableReaderCaller::kCompaction, /*arena=*/nullptr, /*skip_filters=*/false, /*level=*/static_cast(c->level(which)), MaxFileSizeForL0MetaPin(*c->mutable_cf_options()), /*smallest_compaction_key=*/nullptr, /*largest_compaction_key=*/nullptr, /*allow_unprepared_value=*/false); } } else { // Create concatenating iterator for the files from this level list[num++] = new LevelIterator( cfd->table_cache(), read_options, file_options_compactions, cfd->internal_comparator(), c->input_levels(which), c->mutable_cf_options()->prefix_extractor.get(), /*should_sample=*/false, /*no per level latency histogram=*/nullptr, TableReaderCaller::kCompaction, /*skip_filters=*/false, /*level=*/static_cast(c->level(which)), range_del_agg, c->boundaries(which)); } } } assert(num <= space); InternalIterator* result = NewMergingIterator(&c->column_family_data()->internal_comparator(), list, static_cast(num)); delete[] list; return result; } // verify that the files listed in this compaction are present // in the current version bool VersionSet::VerifyCompactionFileConsistency(Compaction* c) { #ifndef NDEBUG Version* version = c->column_family_data()->current(); const VersionStorageInfo* vstorage = version->storage_info(); if (c->input_version() != version) { ROCKS_LOG_INFO( db_options_->info_log, "[%s] compaction output being applied to a different base version from" " input version", c->column_family_data()->GetName().c_str()); if (vstorage->compaction_style_ == kCompactionStyleLevel && c->start_level() == 0 && c->num_input_levels() > 2U) { // We are doing a L0->base_level compaction. The assumption is if // base level is not L1, levels from L1 to base_level - 1 is empty. // This is ensured by having one compaction from L0 going on at the // same time in level-based compaction. So that during the time, no // compaction/flush can put files to those levels. for (int l = c->start_level() + 1; l < c->output_level(); l++) { if (vstorage->NumLevelFiles(l) != 0) { return false; } } } } for (size_t input = 0; input < c->num_input_levels(); ++input) { int level = c->level(input); for (size_t i = 0; i < c->num_input_files(input); ++i) { uint64_t number = c->input(input, i)->fd.GetNumber(); bool found = false; for (size_t j = 0; j < vstorage->files_[level].size(); j++) { FileMetaData* f = vstorage->files_[level][j]; if (f->fd.GetNumber() == number) { found = true; break; } } if (!found) { return false; // input files non existent in current version } } } #else (void)c; #endif return true; // everything good } Status VersionSet::GetMetadataForFile(uint64_t number, int* filelevel, FileMetaData** meta, ColumnFamilyData** cfd) { for (auto cfd_iter : *column_family_set_) { if (!cfd_iter->initialized()) { continue; } Version* version = cfd_iter->current(); const auto* vstorage = version->storage_info(); for (int level = 0; level < vstorage->num_levels(); level++) { for (const auto& file : vstorage->LevelFiles(level)) { if (file->fd.GetNumber() == number) { *meta = file; *filelevel = level; *cfd = cfd_iter; return Status::OK(); } } } } return Status::NotFound("File not present in any level"); } void VersionSet::GetLiveFilesMetaData(std::vector* metadata) { for (auto cfd : *column_family_set_) { if (cfd->IsDropped() || !cfd->initialized()) { continue; } for (int level = 0; level < cfd->NumberLevels(); level++) { for (const auto& file : cfd->current()->storage_info()->LevelFiles(level)) { LiveFileMetaData filemetadata; filemetadata.column_family_name = cfd->GetName(); uint32_t path_id = file->fd.GetPathId(); if (path_id < cfd->ioptions()->cf_paths.size()) { filemetadata.db_path = cfd->ioptions()->cf_paths[path_id].path; } else { assert(!cfd->ioptions()->cf_paths.empty()); filemetadata.db_path = cfd->ioptions()->cf_paths.back().path; } const uint64_t file_number = file->fd.GetNumber(); filemetadata.name = MakeTableFileName("", file_number); filemetadata.file_number = file_number; filemetadata.level = level; filemetadata.size = static_cast(file->fd.GetFileSize()); filemetadata.smallestkey = file->smallest.user_key().ToString(); filemetadata.largestkey = file->largest.user_key().ToString(); filemetadata.smallest_seqno = file->fd.smallest_seqno; filemetadata.largest_seqno = file->fd.largest_seqno; filemetadata.num_reads_sampled = file->stats.num_reads_sampled.load( std::memory_order_relaxed); filemetadata.being_compacted = file->being_compacted; filemetadata.num_entries = file->num_entries; filemetadata.num_deletions = file->num_deletions; filemetadata.oldest_blob_file_number = file->oldest_blob_file_number; filemetadata.file_checksum = file->file_checksum; filemetadata.file_checksum_func_name = file->file_checksum_func_name; metadata->push_back(filemetadata); } } } } void VersionSet::GetObsoleteFiles(std::vector* files, std::vector* blob_files, std::vector* manifest_filenames, uint64_t min_pending_output) { assert(files); assert(blob_files); assert(manifest_filenames); assert(files->empty()); assert(blob_files->empty()); assert(manifest_filenames->empty()); std::vector pending_files; for (auto& f : obsolete_files_) { if (f.metadata->fd.GetNumber() < min_pending_output) { files->emplace_back(std::move(f)); } else { pending_files.emplace_back(std::move(f)); } } obsolete_files_.swap(pending_files); std::vector pending_blob_files; for (auto& blob_file : obsolete_blob_files_) { if (blob_file.GetBlobFileNumber() < min_pending_output) { blob_files->emplace_back(std::move(blob_file)); } else { pending_blob_files.emplace_back(std::move(blob_file)); } } obsolete_blob_files_.swap(pending_blob_files); obsolete_manifests_.swap(*manifest_filenames); } ColumnFamilyData* VersionSet::CreateColumnFamily( const ColumnFamilyOptions& cf_options, const VersionEdit* edit) { assert(edit->is_column_family_add_); MutableCFOptions dummy_cf_options; Version* dummy_versions = new Version(nullptr, this, file_options_, dummy_cf_options, io_tracer_); // Ref() dummy version once so that later we can call Unref() to delete it // by avoiding calling "delete" explicitly (~Version is private) dummy_versions->Ref(); auto new_cfd = column_family_set_->CreateColumnFamily( edit->column_family_name_, edit->column_family_, dummy_versions, cf_options); Version* v = new Version(new_cfd, this, file_options_, *new_cfd->GetLatestMutableCFOptions(), io_tracer_, current_version_number_++); // Fill level target base information. v->storage_info()->CalculateBaseBytes(*new_cfd->ioptions(), *new_cfd->GetLatestMutableCFOptions()); AppendVersion(new_cfd, v); // GetLatestMutableCFOptions() is safe here without mutex since the // cfd is not available to client new_cfd->CreateNewMemtable(*new_cfd->GetLatestMutableCFOptions(), LastSequence()); new_cfd->SetLogNumber(edit->log_number_); return new_cfd; } uint64_t VersionSet::GetNumLiveVersions(Version* dummy_versions) { uint64_t count = 0; for (Version* v = dummy_versions->next_; v != dummy_versions; v = v->next_) { count++; } return count; } uint64_t VersionSet::GetTotalSstFilesSize(Version* dummy_versions) { std::unordered_set unique_files; uint64_t total_files_size = 0; for (Version* v = dummy_versions->next_; v != dummy_versions; v = v->next_) { VersionStorageInfo* storage_info = v->storage_info(); for (int level = 0; level < storage_info->num_levels_; level++) { for (const auto& file_meta : storage_info->LevelFiles(level)) { if (unique_files.find(file_meta->fd.packed_number_and_path_id) == unique_files.end()) { unique_files.insert(file_meta->fd.packed_number_and_path_id); total_files_size += file_meta->fd.GetFileSize(); } } } } return total_files_size; } Status VersionSet::VerifyFileMetadata(const std::string& fpath, const FileMetaData& meta) const { uint64_t fsize = 0; Status status = fs_->GetFileSize(fpath, IOOptions(), &fsize, nullptr); if (status.ok()) { if (fsize != meta.fd.GetFileSize()) { status = Status::Corruption("File size mismatch: " + fpath); } } return status; } ReactiveVersionSet::ReactiveVersionSet( const std::string& dbname, const ImmutableDBOptions* _db_options, const FileOptions& _file_options, Cache* table_cache, WriteBufferManager* write_buffer_manager, WriteController* write_controller, const std::shared_ptr& io_tracer) : VersionSet(dbname, _db_options, _file_options, table_cache, write_buffer_manager, write_controller, /*block_cache_tracer=*/nullptr, io_tracer), number_of_edits_to_skip_(0) {} ReactiveVersionSet::~ReactiveVersionSet() {} Status ReactiveVersionSet::Recover( const std::vector& column_families, std::unique_ptr* manifest_reader, std::unique_ptr* manifest_reporter, std::unique_ptr* manifest_reader_status) { assert(manifest_reader != nullptr); assert(manifest_reporter != nullptr); assert(manifest_reader_status != nullptr); std::unordered_map cf_name_to_options; for (const auto& cf : column_families) { cf_name_to_options.insert({cf.name, cf.options}); } // add default column family auto default_cf_iter = cf_name_to_options.find(kDefaultColumnFamilyName); if (default_cf_iter == cf_name_to_options.end()) { return Status::InvalidArgument("Default column family not specified"); } VersionEdit default_cf_edit; default_cf_edit.AddColumnFamily(kDefaultColumnFamilyName); default_cf_edit.SetColumnFamily(0); ColumnFamilyData* default_cfd = CreateColumnFamily(default_cf_iter->second, &default_cf_edit); // In recovery, nobody else can access it, so it's fine to set it to be // initialized earlier. default_cfd->set_initialized(); VersionBuilderMap builders; std::unordered_map column_families_not_found; builders.insert( std::make_pair(0, std::unique_ptr( new BaseReferencedVersionBuilder(default_cfd)))); manifest_reader_status->reset(new Status()); manifest_reporter->reset(new LogReporter()); static_cast_with_check(manifest_reporter->get())->status = manifest_reader_status->get(); Status s = MaybeSwitchManifest(manifest_reporter->get(), manifest_reader); log::Reader* reader = manifest_reader->get(); int retry = 0; VersionEdit version_edit; while (s.ok() && retry < 1) { assert(reader != nullptr); s = ReadAndRecover(*reader, &read_buffer_, cf_name_to_options, column_families_not_found, builders, manifest_reader_status->get(), &version_edit); if (s.ok()) { bool enough = version_edit.has_next_file_number_ && version_edit.has_log_number_ && version_edit.has_last_sequence_; if (enough) { for (const auto& cf : column_families) { auto cfd = column_family_set_->GetColumnFamily(cf.name); if (cfd == nullptr) { enough = false; break; } } } if (enough) { for (const auto& cf : column_families) { auto cfd = column_family_set_->GetColumnFamily(cf.name); assert(cfd != nullptr); if (!cfd->IsDropped()) { auto builder_iter = builders.find(cfd->GetID()); assert(builder_iter != builders.end()); auto builder = builder_iter->second->version_builder(); assert(builder != nullptr); s = builder->LoadTableHandlers( cfd->internal_stats(), db_options_->max_file_opening_threads, false /* prefetch_index_and_filter_in_cache */, true /* is_initial_load */, cfd->GetLatestMutableCFOptions()->prefix_extractor.get(), MaxFileSizeForL0MetaPin(*cfd->GetLatestMutableCFOptions())); if (!s.ok()) { enough = false; if (s.IsPathNotFound()) { s = Status::OK(); } break; } } } } if (enough) { break; } } ++retry; } if (s.ok()) { if (!version_edit.has_prev_log_number_) { version_edit.prev_log_number_ = 0; } column_family_set_->UpdateMaxColumnFamily(version_edit.max_column_family_); MarkMinLogNumberToKeep2PC(version_edit.min_log_number_to_keep_); MarkFileNumberUsed(version_edit.prev_log_number_); MarkFileNumberUsed(version_edit.log_number_); for (auto cfd : *column_family_set_) { assert(builders.count(cfd->GetID()) > 0); auto builder = builders[cfd->GetID()]->version_builder(); if (!builder->CheckConsistencyForNumLevels()) { s = Status::InvalidArgument( "db has more levels than options.num_levels"); break; } } } if (s.ok()) { for (auto cfd : *column_family_set_) { if (cfd->IsDropped()) { continue; } assert(cfd->initialized()); auto builders_iter = builders.find(cfd->GetID()); assert(builders_iter != builders.end()); auto* builder = builders_iter->second->version_builder(); Version* v = new Version(cfd, this, file_options_, *cfd->GetLatestMutableCFOptions(), io_tracer_, current_version_number_++); s = builder->SaveTo(v->storage_info()); if (s.ok()) { // Install recovered version v->PrepareApply(*cfd->GetLatestMutableCFOptions(), !(db_options_->skip_stats_update_on_db_open)); AppendVersion(cfd, v); } else { ROCKS_LOG_ERROR(db_options_->info_log, "[%s]: inconsistent version: %s\n", cfd->GetName().c_str(), s.ToString().c_str()); delete v; break; } } } if (s.ok()) { next_file_number_.store(version_edit.next_file_number_ + 1); last_allocated_sequence_ = version_edit.last_sequence_; last_published_sequence_ = version_edit.last_sequence_; last_sequence_ = version_edit.last_sequence_; prev_log_number_ = version_edit.prev_log_number_; for (auto cfd : *column_family_set_) { if (cfd->IsDropped()) { continue; } ROCKS_LOG_INFO(db_options_->info_log, "Column family [%s] (ID %u), log number is %" PRIu64 "\n", cfd->GetName().c_str(), cfd->GetID(), cfd->GetLogNumber()); } } return s; } Status ReactiveVersionSet::ReadAndApply( InstrumentedMutex* mu, std::unique_ptr* manifest_reader, std::unordered_set* cfds_changed) { assert(manifest_reader != nullptr); assert(cfds_changed != nullptr); mu->AssertHeld(); Status s; uint64_t applied_edits = 0; while (s.ok()) { Slice record; std::string scratch; log::Reader* reader = manifest_reader->get(); std::string old_manifest_path = reader->file()->file_name(); while (reader->ReadRecord(&record, &scratch)) { VersionEdit edit; s = edit.DecodeFrom(record); if (!s.ok()) { break; } // Skip the first VersionEdits of each MANIFEST generated by // VersionSet::WriteCurrentStatetoManifest. if (number_of_edits_to_skip_ > 0) { ColumnFamilyData* cfd = column_family_set_->GetColumnFamily(edit.column_family_); if (cfd != nullptr && !cfd->IsDropped()) { --number_of_edits_to_skip_; } continue; } s = read_buffer_.AddEdit(&edit); if (!s.ok()) { break; } VersionEdit temp_edit; if (edit.is_in_atomic_group_) { if (read_buffer_.IsFull()) { // Apply edits in an atomic group when we have read all edits in the // group. for (auto& e : read_buffer_.replay_buffer()) { s = ApplyOneVersionEditToBuilder(e, cfds_changed, &temp_edit); if (!s.ok()) { break; } applied_edits++; } if (!s.ok()) { break; } read_buffer_.Clear(); } } else { // Apply a normal edit immediately. s = ApplyOneVersionEditToBuilder(edit, cfds_changed, &temp_edit); if (s.ok()) { applied_edits++; } else { break; } } } if (!s.ok()) { // Clear the buffer if we fail to decode/apply an edit. read_buffer_.Clear(); } // It's possible that: // 1) s.IsCorruption(), indicating the current MANIFEST is corrupted. // Or the version(s) rebuilt from tailing the MANIFEST is inconsistent. // 2) we have finished reading the current MANIFEST. // 3) we have encountered an IOError reading the current MANIFEST. // We need to look for the next MANIFEST and start from there. If we cannot // find the next MANIFEST, we should exit the loop. Status tmp_s = MaybeSwitchManifest(reader->GetReporter(), manifest_reader); reader = manifest_reader->get(); if (tmp_s.ok()) { if (reader->file()->file_name() == old_manifest_path) { // Still processing the same MANIFEST, thus no need to continue this // loop since no record is available if we have reached here. break; } else { // We have switched to a new MANIFEST whose first records have been // generated by VersionSet::WriteCurrentStatetoManifest. Since the // secondary instance has already finished recovering upon start, there // is no need for the secondary to process these records. Actually, if // the secondary were to replay these records, the secondary may end up // adding the same SST files AGAIN to each column family, causing // consistency checks done by VersionBuilder to fail. Therefore, we // record the number of records to skip at the beginning of the new // MANIFEST and ignore them. number_of_edits_to_skip_ = 0; for (auto* cfd : *column_family_set_) { if (cfd->IsDropped()) { continue; } // Increase number_of_edits_to_skip by 2 because // WriteCurrentStatetoManifest() writes 2 version edits for each // column family at the beginning of the newly-generated MANIFEST. // TODO(yanqin) remove hard-coded value. if (db_options_->write_dbid_to_manifest) { number_of_edits_to_skip_ += 3; } else { number_of_edits_to_skip_ += 2; } } s = tmp_s; } } } if (s.ok()) { for (auto cfd : *column_family_set_) { auto builder_iter = active_version_builders_.find(cfd->GetID()); if (builder_iter == active_version_builders_.end()) { continue; } auto builder = builder_iter->second->version_builder(); if (!builder->CheckConsistencyForNumLevels()) { s = Status::InvalidArgument( "db has more levels than options.num_levels"); break; } } } TEST_SYNC_POINT_CALLBACK("ReactiveVersionSet::ReadAndApply:AppliedEdits", &applied_edits); return s; } Status ReactiveVersionSet::ApplyOneVersionEditToBuilder( VersionEdit& edit, std::unordered_set* cfds_changed, VersionEdit* version_edit) { ColumnFamilyData* cfd = column_family_set_->GetColumnFamily(edit.column_family_); // If we cannot find this column family in our column family set, then it // may be a new column family created by the primary after the secondary // starts. It is also possible that the secondary instance opens only a subset // of column families. Ignore it for now. if (nullptr == cfd) { return Status::OK(); } if (active_version_builders_.find(edit.column_family_) == active_version_builders_.end() && !cfd->IsDropped()) { std::unique_ptr builder_guard( new BaseReferencedVersionBuilder(cfd)); active_version_builders_.insert( std::make_pair(edit.column_family_, std::move(builder_guard))); } auto builder_iter = active_version_builders_.find(edit.column_family_); assert(builder_iter != active_version_builders_.end()); auto builder = builder_iter->second->version_builder(); assert(builder != nullptr); if (edit.is_column_family_add_) { // TODO (yanqin) for now the secondary ignores column families created // after Open. This also simplifies handling of switching to a new MANIFEST // and processing the snapshot of the system at the beginning of the // MANIFEST. } else if (edit.is_column_family_drop_) { // Drop the column family by setting it to be 'dropped' without destroying // the column family handle. // TODO (haoyu) figure out how to handle column faimly drop for // secondary instance. (Is it possible that the ref count for cfd is 0 but // the ref count for its versions is higher than 0?) cfd->SetDropped(); if (cfd->UnrefAndTryDelete()) { cfd = nullptr; } active_version_builders_.erase(builder_iter); } else { Status s = builder->Apply(&edit); if (!s.ok()) { return s; } } Status s = ExtractInfoFromVersionEdit(cfd, edit, version_edit); if (!s.ok()) { return s; } if (cfd != nullptr && !cfd->IsDropped()) { s = builder->LoadTableHandlers( cfd->internal_stats(), db_options_->max_file_opening_threads, false /* prefetch_index_and_filter_in_cache */, false /* is_initial_load */, cfd->GetLatestMutableCFOptions()->prefix_extractor.get(), MaxFileSizeForL0MetaPin(*cfd->GetLatestMutableCFOptions())); TEST_SYNC_POINT_CALLBACK( "ReactiveVersionSet::ApplyOneVersionEditToBuilder:" "AfterLoadTableHandlers", &s); if (s.ok()) { auto version = new Version(cfd, this, file_options_, *cfd->GetLatestMutableCFOptions(), io_tracer_, current_version_number_++); s = builder->SaveTo(version->storage_info()); if (s.ok()) { version->PrepareApply(*cfd->GetLatestMutableCFOptions(), true); AppendVersion(cfd, version); active_version_builders_.erase(builder_iter); if (cfds_changed->count(cfd) == 0) { cfds_changed->insert(cfd); } } else { delete version; } } else if (s.IsPathNotFound()) { s = Status::OK(); } // Some other error has occurred during LoadTableHandlers. } if (s.ok()) { if (version_edit->HasNextFile()) { next_file_number_.store(version_edit->next_file_number_ + 1); } if (version_edit->has_last_sequence_) { last_allocated_sequence_ = version_edit->last_sequence_; last_published_sequence_ = version_edit->last_sequence_; last_sequence_ = version_edit->last_sequence_; } if (version_edit->has_prev_log_number_) { prev_log_number_ = version_edit->prev_log_number_; MarkFileNumberUsed(version_edit->prev_log_number_); } if (version_edit->has_log_number_) { MarkFileNumberUsed(version_edit->log_number_); } column_family_set_->UpdateMaxColumnFamily(version_edit->max_column_family_); MarkMinLogNumberToKeep2PC(version_edit->min_log_number_to_keep_); } return s; } Status ReactiveVersionSet::MaybeSwitchManifest( log::Reader::Reporter* reporter, std::unique_ptr* manifest_reader) { assert(manifest_reader != nullptr); Status s; do { std::string manifest_path; s = GetCurrentManifestPath(dbname_, fs_.get(), &manifest_path, &manifest_file_number_); std::unique_ptr manifest_file; if (s.ok()) { if (nullptr == manifest_reader->get() || manifest_reader->get()->file()->file_name() != manifest_path) { TEST_SYNC_POINT( "ReactiveVersionSet::MaybeSwitchManifest:" "AfterGetCurrentManifestPath:0"); TEST_SYNC_POINT( "ReactiveVersionSet::MaybeSwitchManifest:" "AfterGetCurrentManifestPath:1"); s = fs_->NewSequentialFile(manifest_path, fs_->OptimizeForManifestRead(file_options_), &manifest_file, nullptr); } else { // No need to switch manifest. break; } } std::unique_ptr manifest_file_reader; if (s.ok()) { manifest_file_reader.reset(new SequentialFileReader( std::move(manifest_file), manifest_path, db_options_->log_readahead_size, io_tracer_)); manifest_reader->reset(new log::FragmentBufferedReader( nullptr, std::move(manifest_file_reader), reporter, true /* checksum */, 0 /* log_number */)); ROCKS_LOG_INFO(db_options_->info_log, "Switched to new manifest: %s\n", manifest_path.c_str()); // TODO (yanqin) every time we switch to a new MANIFEST, we clear the // active_version_builders_ map because we choose to construct the // versions from scratch, thanks to the first part of each MANIFEST // written by VersionSet::WriteCurrentStatetoManifest. This is not // necessary, but we choose this at present for the sake of simplicity. active_version_builders_.clear(); } } while (s.IsPathNotFound()); return s; } } // namespace ROCKSDB_NAMESPACE