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rocksdb/db/db_impl.cc

5785 lines
200 KiB

// Copyright (c) 2013, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same 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/db_impl.h"
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>
#include <stdint.h>
#include <algorithm>
#include <climits>
#include <cstdio>
#include <map>
#include <set>
#include <stdexcept>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
#include "db/builder.h"
#include "db/compaction_job.h"
#include "db/db_iter.h"
#include "db/dbformat.h"
#include "db/event_helpers.h"
#include "db/filename.h"
#include "db/flush_job.h"
#include "db/forward_iterator.h"
#include "db/job_context.h"
#include "db/log_reader.h"
#include "db/log_writer.h"
#include "db/managed_iterator.h"
#include "db/memtable.h"
#include "db/memtable_list.h"
#include "db/merge_context.h"
#include "db/merge_helper.h"
#include "db/table_cache.h"
#include "db/table_properties_collector.h"
#include "db/transaction_log_impl.h"
#include "db/version_set.h"
#include "db/write_batch_internal.h"
#include "db/write_callback.h"
#include "db/writebuffer.h"
#include "memtable/hash_linklist_rep.h"
#include "memtable/hash_skiplist_rep.h"
#include "port/likely.h"
#include "port/port.h"
#include "rocksdb/cache.h"
#include "rocksdb/compaction_filter.h"
#include "rocksdb/db.h"
#include "rocksdb/delete_scheduler.h"
#include "rocksdb/env.h"
#include "rocksdb/merge_operator.h"
#include "rocksdb/sst_file_writer.h"
#include "rocksdb/statistics.h"
#include "rocksdb/status.h"
#include "rocksdb/table.h"
#include "rocksdb/version.h"
#include "rocksdb/wal_filter.h"
#include "table/block.h"
#include "table/block_based_table_factory.h"
#include "table/merger.h"
#include "table/table_builder.h"
#include "table/two_level_iterator.h"
#include "util/auto_roll_logger.h"
#include "util/autovector.h"
#include "util/build_version.h"
#include "util/coding.h"
#include "util/compression.h"
#include "util/crc32c.h"
#include "util/db_info_dumper.h"
#include "util/file_reader_writer.h"
#include "util/file_util.h"
#include "util/iostats_context_imp.h"
#include "util/log_buffer.h"
#include "util/logging.h"
#include "util/mutexlock.h"
#include "util/options_helper.h"
#include "util/options_parser.h"
#include "util/perf_context_imp.h"
#include "util/stop_watch.h"
#include "util/string_util.h"
#include "util/sync_point.h"
#include "util/thread_status_updater.h"
#include "util/thread_status_util.h"
#include "util/xfunc.h"
namespace rocksdb {
const std::string kDefaultColumnFamilyName("default");
void DumpRocksDBBuildVersion(Logger * log);
struct DBImpl::WriteContext {
autovector<SuperVersion*> superversions_to_free_;
autovector<MemTable*> memtables_to_free_;
~WriteContext() {
for (auto& sv : superversions_to_free_) {
delete sv;
}
for (auto& m : memtables_to_free_) {
delete m;
}
}
};
Options SanitizeOptions(const std::string& dbname,
const InternalKeyComparator* icmp,
const Options& src) {
auto db_options = SanitizeOptions(dbname, DBOptions(src));
auto cf_options = SanitizeOptions(db_options, icmp, ColumnFamilyOptions(src));
return Options(db_options, cf_options);
}
DBOptions SanitizeOptions(const std::string& dbname, const DBOptions& src) {
DBOptions result = src;
// result.max_open_files means an "infinite" open files.
if (result.max_open_files != -1) {
int max_max_open_files = port::GetMaxOpenFiles();
if (max_max_open_files == -1) {
max_max_open_files = 1000000;
}
ClipToRange(&result.max_open_files, 20, max_max_open_files);
}
if (result.info_log == nullptr) {
Status s = CreateLoggerFromOptions(dbname, result, &result.info_log);
if (!s.ok()) {
// No place suitable for logging
result.info_log = nullptr;
}
}
result.env->IncBackgroundThreadsIfNeeded(src.max_background_compactions,
Env::Priority::LOW);
result.env->IncBackgroundThreadsIfNeeded(src.max_background_flushes,
Env::Priority::HIGH);
if (result.rate_limiter.get() != nullptr) {
if (result.bytes_per_sync == 0) {
result.bytes_per_sync = 1024 * 1024;
}
}
if (result.WAL_ttl_seconds > 0 || result.WAL_size_limit_MB > 0) {
result.recycle_log_file_num = false;
}
if (result.wal_dir.empty()) {
// Use dbname as default
result.wal_dir = dbname;
}
if (result.wal_dir.back() == '/') {
result.wal_dir = result.wal_dir.substr(0, result.wal_dir.size() - 1);
}
if (result.db_paths.size() == 0) {
result.db_paths.emplace_back(dbname, std::numeric_limits<uint64_t>::max());
}
if (result.compaction_readahead_size > 0) {
result.new_table_reader_for_compaction_inputs = true;
}
return result;
}
namespace {
Status SanitizeOptionsByTable(
const DBOptions& db_opts,
const std::vector<ColumnFamilyDescriptor>& column_families) {
Status s;
for (auto cf : column_families) {
s = cf.options.table_factory->SanitizeOptions(db_opts, cf.options);
if (!s.ok()) {
return s;
}
}
return Status::OK();
}
CompressionType GetCompressionFlush(const ImmutableCFOptions& ioptions) {
// Compressing memtable flushes might not help unless the sequential load
// optimization is used for leveled compaction. Otherwise the CPU and
// latency overhead is not offset by saving much space.
bool can_compress;
if (ioptions.compaction_style == kCompactionStyleUniversal) {
can_compress =
(ioptions.compaction_options_universal.compression_size_percent < 0);
} else {
// For leveled compress when min_level_to_compress == 0.
can_compress = ioptions.compression_per_level.empty() ||
ioptions.compression_per_level[0] != kNoCompression;
}
if (can_compress) {
return ioptions.compression;
} else {
return kNoCompression;
}
}
void DumpSupportInfo(Logger* logger) {
Log(InfoLogLevel::INFO_LEVEL, logger, "Compression algorithms supported:");
Log(InfoLogLevel::INFO_LEVEL, logger, "\tSnappy supported: %d",
Snappy_Supported());
Log(InfoLogLevel::INFO_LEVEL, logger, "\tZlib supported: %d",
Zlib_Supported());
Log(InfoLogLevel::INFO_LEVEL, logger, "\tBzip supported: %d",
BZip2_Supported());
Log(InfoLogLevel::INFO_LEVEL, logger, "\tLZ4 supported: %d", LZ4_Supported());
Log(InfoLogLevel::INFO_LEVEL, logger, "Fast CRC32 supported: %d",
crc32c::IsFastCrc32Supported());
}
} // namespace
DBImpl::DBImpl(const DBOptions& options, const std::string& dbname)
: env_(options.env),
dbname_(dbname),
db_options_(SanitizeOptions(dbname, options)),
stats_(db_options_.statistics.get()),
db_lock_(nullptr),
mutex_(stats_, env_, DB_MUTEX_WAIT_MICROS, options.use_adaptive_mutex),
shutting_down_(false),
bg_cv_(&mutex_),
logfile_number_(0),
log_dir_synced_(false),
log_empty_(true),
default_cf_handle_(nullptr),
log_sync_cv_(&mutex_),
total_log_size_(0),
max_total_in_memory_state_(0),
is_snapshot_supported_(true),
write_buffer_(options.db_write_buffer_size),
write_thread_(options.enable_write_thread_adaptive_yield
? options.write_thread_max_yield_usec
: 0,
options.write_thread_slow_yield_usec),
write_controller_(options.delayed_write_rate),
last_batch_group_size_(0),
unscheduled_flushes_(0),
unscheduled_compactions_(0),
bg_compaction_scheduled_(0),
num_running_compactions_(0),
bg_flush_scheduled_(0),
num_running_flushes_(0),
disable_delete_obsolete_files_(0),
delete_obsolete_files_next_run_(
options.env->NowMicros() +
db_options_.delete_obsolete_files_period_micros),
last_stats_dump_time_microsec_(0),
next_job_id_(1),
flush_on_destroy_(false),
env_options_(db_options_),
#ifndef ROCKSDB_LITE
wal_manager_(db_options_, env_options_),
#endif // ROCKSDB_LITE
event_logger_(db_options_.info_log.get()),
bg_work_paused_(0),
refitting_level_(false),
opened_successfully_(false) {
env_->GetAbsolutePath(dbname, &db_absolute_path_);
// Reserve ten files or so for other uses and give the rest to TableCache.
// Give a large number for setting of "infinite" open files.
const int table_cache_size = (db_options_.max_open_files == -1) ?
4194304 : db_options_.max_open_files - 10;
table_cache_ =
NewLRUCache(table_cache_size, db_options_.table_cache_numshardbits);
versions_.reset(new VersionSet(dbname_, &db_options_, env_options_,
table_cache_.get(), &write_buffer_,
&write_controller_));
column_family_memtables_.reset(
new ColumnFamilyMemTablesImpl(versions_->GetColumnFamilySet()));
DumpRocksDBBuildVersion(db_options_.info_log.get());
DumpDBFileSummary(db_options_, dbname_);
db_options_.Dump(db_options_.info_log.get());
DumpSupportInfo(db_options_.info_log.get());
}
// Will lock the mutex_, will wait for completion if wait is true
void DBImpl::CancelAllBackgroundWork(bool wait) {
InstrumentedMutexLock l(&mutex_);
shutting_down_.store(true, std::memory_order_release);
bg_cv_.SignalAll();
if (!wait) {
return;
}
// Wait for background work to finish
while (bg_compaction_scheduled_ || bg_flush_scheduled_) {
bg_cv_.Wait();
}
}
DBImpl::~DBImpl() {
mutex_.Lock();
if (!shutting_down_.load(std::memory_order_acquire) && flush_on_destroy_) {
for (auto cfd : *versions_->GetColumnFamilySet()) {
if (!cfd->IsDropped() && !cfd->mem()->IsEmpty()) {
cfd->Ref();
mutex_.Unlock();
FlushMemTable(cfd, FlushOptions());
mutex_.Lock();
cfd->Unref();
}
}
versions_->GetColumnFamilySet()->FreeDeadColumnFamilies();
}
mutex_.Unlock();
// CancelAllBackgroundWork called with false means we just set the shutdown
// marker. After this we do a variant of the waiting and unschedule work
// (to consider: moving all the waiting into CancelAllBackgroundWork(true))
CancelAllBackgroundWork(false);
int compactions_unscheduled = env_->UnSchedule(this, Env::Priority::LOW);
int flushes_unscheduled = env_->UnSchedule(this, Env::Priority::HIGH);
mutex_.Lock();
bg_compaction_scheduled_ -= compactions_unscheduled;
bg_flush_scheduled_ -= flushes_unscheduled;
// Wait for background work to finish
while (bg_compaction_scheduled_ || bg_flush_scheduled_) {
bg_cv_.Wait();
}
EraseThreadStatusDbInfo();
flush_scheduler_.Clear();
while (!flush_queue_.empty()) {
auto cfd = PopFirstFromFlushQueue();
if (cfd->Unref()) {
delete cfd;
}
}
while (!compaction_queue_.empty()) {
auto cfd = PopFirstFromCompactionQueue();
if (cfd->Unref()) {
delete cfd;
}
}
if (default_cf_handle_ != nullptr) {
// we need to delete handle outside of lock because it does its own locking
mutex_.Unlock();
delete default_cf_handle_;
mutex_.Lock();
}
// Clean up obsolete files due to SuperVersion release.
// (1) Need to delete to obsolete files before closing because RepairDB()
// scans all existing files in the file system and builds manifest file.
// Keeping obsolete files confuses the repair process.
// (2) Need to check if we Open()/Recover() the DB successfully before
// deleting because if VersionSet recover fails (may be due to corrupted
// manifest file), it is not able to identify live files correctly. As a
// result, all "live" files can get deleted by accident. However, corrupted
// manifest is recoverable by RepairDB().
if (opened_successfully_) {
JobContext job_context(next_job_id_.fetch_add(1));
FindObsoleteFiles(&job_context, true);
mutex_.Unlock();
// manifest number starting from 2
job_context.manifest_file_number = 1;
if (job_context.HaveSomethingToDelete()) {
PurgeObsoleteFiles(job_context);
}
job_context.Clean();
mutex_.Lock();
}
for (auto l : logs_to_free_) {
delete l;
}
for (auto& log : logs_) {
log.ClearWriter();
}
logs_.clear();
// versions need to be destroyed before table_cache since it can hold
// references to table_cache.
versions_.reset();
mutex_.Unlock();
if (db_lock_ != nullptr) {
env_->UnlockFile(db_lock_);
}
LogFlush(db_options_.info_log);
}
Status DBImpl::NewDB() {
VersionEdit new_db;
new_db.SetLogNumber(0);
new_db.SetNextFile(2);
new_db.SetLastSequence(0);
Status s;
Log(InfoLogLevel::INFO_LEVEL,
db_options_.info_log, "Creating manifest 1 \n");
const std::string manifest = DescriptorFileName(dbname_, 1);
{
unique_ptr<WritableFile> file;
EnvOptions env_options = env_->OptimizeForManifestWrite(env_options_);
s = NewWritableFile(env_, manifest, &file, env_options);
if (!s.ok()) {
return s;
}
file->SetPreallocationBlockSize(db_options_.manifest_preallocation_size);
unique_ptr<WritableFileWriter> file_writer(
new WritableFileWriter(std::move(file), env_options));
log::Writer log(std::move(file_writer), 0, false);
std::string record;
new_db.EncodeTo(&record);
s = log.AddRecord(record);
if (s.ok()) {
s = SyncManifest(env_, &db_options_, log.file());
}
}
if (s.ok()) {
// Make "CURRENT" file that points to the new manifest file.
s = SetCurrentFile(env_, dbname_, 1, directories_.GetDbDir());
} else {
env_->DeleteFile(manifest);
}
return s;
}
void DBImpl::MaybeIgnoreError(Status* s) const {
if (s->ok() || db_options_.paranoid_checks) {
// No change needed
} else {
Log(InfoLogLevel::WARN_LEVEL,
db_options_.info_log, "Ignoring error %s", s->ToString().c_str());
*s = Status::OK();
}
}
const Status DBImpl::CreateArchivalDirectory() {
if (db_options_.WAL_ttl_seconds > 0 || db_options_.WAL_size_limit_MB > 0) {
std::string archivalPath = ArchivalDirectory(db_options_.wal_dir);
return env_->CreateDirIfMissing(archivalPath);
}
return Status::OK();
}
void DBImpl::PrintStatistics() {
auto dbstats = db_options_.statistics.get();
if (dbstats) {
Log(InfoLogLevel::WARN_LEVEL, db_options_.info_log,
"STATISTICS:\n %s",
dbstats->ToString().c_str());
}
}
void DBImpl::MaybeDumpStats() {
if (db_options_.stats_dump_period_sec == 0) return;
const uint64_t now_micros = env_->NowMicros();
if (last_stats_dump_time_microsec_ +
db_options_.stats_dump_period_sec * 1000000
<= now_micros) {
// Multiple threads could race in here simultaneously.
// However, the last one will update last_stats_dump_time_microsec_
// atomically. We could see more than one dump during one dump
// period in rare cases.
last_stats_dump_time_microsec_ = now_micros;
#ifndef ROCKSDB_LITE
bool tmp1 = false;
bool tmp2 = false;
DBPropertyType cf_property_type =
GetPropertyType(DB::Properties::kCFStats, &tmp1, &tmp2);
DBPropertyType db_property_type =
GetPropertyType(DB::Properties::kDBStats, &tmp1, &tmp2);
std::string stats;
{
InstrumentedMutexLock l(&mutex_);
for (auto cfd : *versions_->GetColumnFamilySet()) {
cfd->internal_stats()->GetStringProperty(cf_property_type,
DB::Properties::kCFStats,
&stats);
}
default_cf_internal_stats_->GetStringProperty(db_property_type,
DB::Properties::kDBStats,
&stats);
}
Log(InfoLogLevel::WARN_LEVEL,
db_options_.info_log, "------- DUMPING STATS -------");
Log(InfoLogLevel::WARN_LEVEL,
db_options_.info_log, "%s", stats.c_str());
#endif // !ROCKSDB_LITE
PrintStatistics();
}
}
// * Returns the list of live files in 'sst_live'
// If it's doing full scan:
// * Returns the list of all files in the filesystem in
// 'full_scan_candidate_files'.
// Otherwise, gets obsolete files from VersionSet.
// no_full_scan = true -- never do the full scan using GetChildren()
// force = false -- don't force the full scan, except every
// db_options_.delete_obsolete_files_period_micros
// force = true -- force the full scan
void DBImpl::FindObsoleteFiles(JobContext* job_context, bool force,
bool no_full_scan) {
mutex_.AssertHeld();
// if deletion is disabled, do nothing
if (disable_delete_obsolete_files_ > 0) {
return;
}
bool doing_the_full_scan = false;
// logic for figurint out if we're doing the full scan
if (no_full_scan) {
doing_the_full_scan = false;
} else if (force || db_options_.delete_obsolete_files_period_micros == 0) {
doing_the_full_scan = true;
} else {
const uint64_t now_micros = env_->NowMicros();
if (delete_obsolete_files_next_run_ < now_micros) {
doing_the_full_scan = true;
delete_obsolete_files_next_run_ =
now_micros + db_options_.delete_obsolete_files_period_micros;
}
}
// don't delete files that might be currently written to from compaction
// threads
// Since job_context->min_pending_output is set, until file scan finishes,
// mutex_ cannot be released. Otherwise, we might see no min_pending_output
// here but later find newer generated unfinalized files while scannint.
if (!pending_outputs_.empty()) {
job_context->min_pending_output = *pending_outputs_.begin();
} else {
// delete all of them
job_context->min_pending_output = std::numeric_limits<uint64_t>::max();
}
// Get obsolete files. This function will also update the list of
// pending files in VersionSet().
versions_->GetObsoleteFiles(&job_context->sst_delete_files,
job_context->min_pending_output);
// store the current filenum, lognum, etc
job_context->manifest_file_number = versions_->manifest_file_number();
job_context->pending_manifest_file_number =
versions_->pending_manifest_file_number();
job_context->log_number = versions_->MinLogNumber();
job_context->prev_log_number = versions_->prev_log_number();
versions_->AddLiveFiles(&job_context->sst_live);
if (doing_the_full_scan) {
for (size_t path_id = 0; path_id < db_options_.db_paths.size(); path_id++) {
// set of all files in the directory. We'll exclude files that are still
// alive in the subsequent processings.
std::vector<std::string> files;
env_->GetChildren(db_options_.db_paths[path_id].path,
&files); // Ignore errors
for (std::string file : files) {
// TODO(icanadi) clean up this mess to avoid having one-off "/" prefixes
job_context->full_scan_candidate_files.emplace_back(
"/" + file, static_cast<uint32_t>(path_id));
}
}
//Add log files in wal_dir
if (db_options_.wal_dir != dbname_) {
std::vector<std::string> log_files;
env_->GetChildren(db_options_.wal_dir, &log_files); // Ignore errors
for (std::string log_file : log_files) {
job_context->full_scan_candidate_files.emplace_back(log_file, 0);
}
}
// Add info log files in db_log_dir
if (!db_options_.db_log_dir.empty() && db_options_.db_log_dir != dbname_) {
std::vector<std::string> info_log_files;
// Ignore errors
env_->GetChildren(db_options_.db_log_dir, &info_log_files);
for (std::string log_file : info_log_files) {
job_context->full_scan_candidate_files.emplace_back(log_file, 0);
}
}
}
if (!alive_log_files_.empty()) {
uint64_t min_log_number = versions_->MinLogNumber();
// find newly obsoleted log files
while (alive_log_files_.begin()->number < min_log_number) {
auto& earliest = *alive_log_files_.begin();
if (db_options_.recycle_log_file_num > log_recycle_files.size()) {
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"adding log %" PRIu64 " to recycle list\n", earliest.number);
log_recycle_files.push_back(earliest.number);
} else {
job_context->log_delete_files.push_back(earliest.number);
}
total_log_size_ -= earliest.size;
alive_log_files_.pop_front();
// Current log should always stay alive since it can't have
// number < MinLogNumber().
assert(alive_log_files_.size());
}
while (!logs_.empty() && logs_.front().number < min_log_number) {
auto& log = logs_.front();
if (log.getting_synced) {
log_sync_cv_.Wait();
// logs_ could have changed while we were waiting.
continue;
}
logs_to_free_.push_back(log.ReleaseWriter());
logs_.pop_front();
}
// Current log cannot be obsolete.
assert(!logs_.empty());
}
// We're just cleaning up for DB::Write().
assert(job_context->logs_to_free.empty());
job_context->logs_to_free = logs_to_free_;
logs_to_free_.clear();
}
namespace {
bool CompareCandidateFile(const JobContext::CandidateFileInfo& first,
const JobContext::CandidateFileInfo& second) {
if (first.file_name > second.file_name) {
return true;
} else if (first.file_name < second.file_name) {
return false;
} else {
return (first.path_id > second.path_id);
}
}
}; // namespace
// Diffs the files listed in filenames and those that do not
// belong to live files are posibly removed. Also, removes all the
// files in sst_delete_files and log_delete_files.
// It is not necessary to hold the mutex when invoking this method.
void DBImpl::PurgeObsoleteFiles(const JobContext& state) {
// we'd better have sth to delete
assert(state.HaveSomethingToDelete());
// this checks if FindObsoleteFiles() was run before. If not, don't do
// PurgeObsoleteFiles(). If FindObsoleteFiles() was run, we need to also
// run PurgeObsoleteFiles(), even if disable_delete_obsolete_files_ is true
if (state.manifest_file_number == 0) {
return;
}
// Now, convert live list to an unordered map, WITHOUT mutex held;
// set is slow.
std::unordered_map<uint64_t, const FileDescriptor*> sst_live_map;
for (const FileDescriptor& fd : state.sst_live) {
sst_live_map[fd.GetNumber()] = &fd;
}
auto candidate_files = state.full_scan_candidate_files;
candidate_files.reserve(candidate_files.size() +
state.sst_delete_files.size() +
state.log_delete_files.size());
// We may ignore the dbname when generating the file names.
const char* kDumbDbName = "";
for (auto file : state.sst_delete_files) {
candidate_files.emplace_back(
MakeTableFileName(kDumbDbName, file->fd.GetNumber()),
file->fd.GetPathId());
delete file;
}
for (auto file_num : state.log_delete_files) {
if (file_num > 0) {
candidate_files.emplace_back(LogFileName(kDumbDbName, file_num).substr(1),
0);
}
}
// dedup state.candidate_files so we don't try to delete the same
// file twice
sort(candidate_files.begin(), candidate_files.end(), CompareCandidateFile);
candidate_files.erase(unique(candidate_files.begin(), candidate_files.end()),
candidate_files.end());
std::vector<std::string> old_info_log_files;
InfoLogPrefix info_log_prefix(!db_options_.db_log_dir.empty(), dbname_);
for (const auto& candidate_file : candidate_files) {
std::string to_delete = candidate_file.file_name;
uint32_t path_id = candidate_file.path_id;
uint64_t number;
FileType type;
// Ignore file if we cannot recognize it.
if (!ParseFileName(to_delete, &number, info_log_prefix.prefix, &type)) {
continue;
}
bool keep = true;
switch (type) {
case kLogFile:
keep = ((number >= state.log_number) ||
(number == state.prev_log_number));
break;
case kDescriptorFile:
// Keep my manifest file, and any newer incarnations'
// (can happen during manifest roll)
keep = (number >= state.manifest_file_number);
break;
case kTableFile:
// If the second condition is not there, this makes
// DontDeletePendingOutputs fail
keep = (sst_live_map.find(number) != sst_live_map.end()) ||
number >= state.min_pending_output;
break;
case kTempFile:
// Any temp files that are currently being written to must
// be recorded in pending_outputs_, which is inserted into "live".
// Also, SetCurrentFile creates a temp file when writing out new
// manifest, which is equal to state.pending_manifest_file_number. We
// should not delete that file
//
// TODO(yhchiang): carefully modify the third condition to safely
// remove the temp options files.
keep = (sst_live_map.find(number) != sst_live_map.end()) ||
(number == state.pending_manifest_file_number) ||
(to_delete.find(kOptionsFileNamePrefix) != std::string::npos);
break;
case kInfoLogFile:
keep = true;
if (number != 0) {
old_info_log_files.push_back(to_delete);
}
break;
case kCurrentFile:
case kDBLockFile:
case kIdentityFile:
case kMetaDatabase:
case kOptionsFile:
keep = true;
break;
}
if (keep) {
continue;
}
std::string fname;
if (type == kTableFile) {
// evict from cache
TableCache::Evict(table_cache_.get(), number);
fname = TableFileName(db_options_.db_paths, number, path_id);
} else {
fname = ((type == kLogFile) ?
db_options_.wal_dir : dbname_) + "/" + to_delete;
}
#ifndef ROCKSDB_LITE
if (type == kLogFile && (db_options_.WAL_ttl_seconds > 0 ||
db_options_.WAL_size_limit_MB > 0)) {
wal_manager_.ArchiveWALFile(fname, number);
continue;
}
#endif // !ROCKSDB_LITE
Status file_deletion_status;
if (type == kTableFile && path_id == 0) {
file_deletion_status = DeleteOrMoveToTrash(&db_options_, fname);
} else {
file_deletion_status = env_->DeleteFile(fname);
}
if (file_deletion_status.ok()) {
Log(InfoLogLevel::DEBUG_LEVEL, db_options_.info_log,
"[JOB %d] Delete %s type=%d #%" PRIu64 " -- %s\n", state.job_id,
fname.c_str(), type, number,
file_deletion_status.ToString().c_str());
} else if (env_->FileExists(fname).IsNotFound()) {
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"[JOB %d] Tried to delete a non-existing file %s type=%d #%" PRIu64
" -- %s\n",
state.job_id, fname.c_str(), type, number,
file_deletion_status.ToString().c_str());
} else {
Log(InfoLogLevel::ERROR_LEVEL, db_options_.info_log,
"[JOB %d] Failed to delete %s type=%d #%" PRIu64 " -- %s\n",
state.job_id, fname.c_str(), type, number,
file_deletion_status.ToString().c_str());
}
if (type == kTableFile) {
EventHelpers::LogAndNotifyTableFileDeletion(
&event_logger_, state.job_id, number, fname,
file_deletion_status, GetName(),
db_options_.listeners);
}
}
// Delete old info log files.
size_t old_info_log_file_count = old_info_log_files.size();
if (old_info_log_file_count >= db_options_.keep_log_file_num) {
std::sort(old_info_log_files.begin(), old_info_log_files.end());
size_t end = old_info_log_file_count - db_options_.keep_log_file_num;
for (unsigned int i = 0; i <= end; i++) {
std::string& to_delete = old_info_log_files.at(i);
std::string full_path_to_delete = (db_options_.db_log_dir.empty() ?
dbname_ : db_options_.db_log_dir) + "/" + to_delete;
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"[JOB %d] Delete info log file %s\n", state.job_id,
full_path_to_delete.c_str());
Status s = env_->DeleteFile(full_path_to_delete);
if (!s.ok()) {
if (env_->FileExists(full_path_to_delete).IsNotFound()) {
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"[JOB %d] Tried to delete non-existing info log file %s FAILED "
"-- %s\n",
state.job_id, to_delete.c_str(), s.ToString().c_str());
} else {
Log(InfoLogLevel::ERROR_LEVEL, db_options_.info_log,
"[JOB %d] Delete info log file %s FAILED -- %s\n", state.job_id,
to_delete.c_str(), s.ToString().c_str());
}
}
}
}
#ifndef ROCKSDB_LITE
wal_manager_.PurgeObsoleteWALFiles();
#endif // ROCKSDB_LITE
LogFlush(db_options_.info_log);
}
void DBImpl::DeleteObsoleteFiles() {
mutex_.AssertHeld();
JobContext job_context(next_job_id_.fetch_add(1));
FindObsoleteFiles(&job_context, true);
mutex_.Unlock();
if (job_context.HaveSomethingToDelete()) {
PurgeObsoleteFiles(job_context);
}
job_context.Clean();
mutex_.Lock();
}
Status DBImpl::Directories::CreateAndNewDirectory(
Env* env, const std::string& dirname,
std::unique_ptr<Directory>* directory) const {
// We call CreateDirIfMissing() as the directory may already exist (if we
// are reopening a DB), when this happens we don't want creating the
// directory to cause an error. However, we need to check if creating the
// directory fails or else we may get an obscure message about the lock
// file not existing. One real-world example of this occurring is if
// env->CreateDirIfMissing() doesn't create intermediate directories, e.g.
// when dbname_ is "dir/db" but when "dir" doesn't exist.
Status s = env->CreateDirIfMissing(dirname);
if (!s.ok()) {
return s;
}
return env->NewDirectory(dirname, directory);
}
Status DBImpl::Directories::SetDirectories(
Env* env, const std::string& dbname, const std::string& wal_dir,
const std::vector<DbPath>& data_paths) {
Status s = CreateAndNewDirectory(env, dbname, &db_dir_);
if (!s.ok()) {
return s;
}
if (!wal_dir.empty() && dbname != wal_dir) {
s = CreateAndNewDirectory(env, wal_dir, &wal_dir_);
if (!s.ok()) {
return s;
}
}
data_dirs_.clear();
for (auto& p : data_paths) {
const std::string db_path = p.path;
if (db_path == dbname) {
data_dirs_.emplace_back(nullptr);
} else {
std::unique_ptr<Directory> path_directory;
s = CreateAndNewDirectory(env, db_path, &path_directory);
if (!s.ok()) {
return s;
}
data_dirs_.emplace_back(path_directory.release());
}
}
assert(data_dirs_.size() == data_paths.size());
return Status::OK();
}
Directory* DBImpl::Directories::GetDataDir(size_t path_id) {
assert(path_id < data_dirs_.size());
Directory* ret_dir = data_dirs_[path_id].get();
if (ret_dir == nullptr) {
// Should use db_dir_
return db_dir_.get();
}
return ret_dir;
}
Status DBImpl::Recover(
const std::vector<ColumnFamilyDescriptor>& column_families, bool read_only,
bool error_if_log_file_exist) {
mutex_.AssertHeld();
bool is_new_db = false;
assert(db_lock_ == nullptr);
if (!read_only) {
Status s = directories_.SetDirectories(env_, dbname_, db_options_.wal_dir,
db_options_.db_paths);
if (!s.ok()) {
return s;
}
s = env_->LockFile(LockFileName(dbname_), &db_lock_);
if (!s.ok()) {
return s;
}
s = env_->FileExists(CurrentFileName(dbname_));
if (s.IsNotFound()) {
if (db_options_.create_if_missing) {
s = NewDB();
is_new_db = true;
if (!s.ok()) {
return s;
}
} else {
return Status::InvalidArgument(
dbname_, "does not exist (create_if_missing is false)");
}
} else if (s.ok()) {
if (db_options_.error_if_exists) {
return Status::InvalidArgument(
dbname_, "exists (error_if_exists is true)");
}
} else {
// Unexpected error reading file
assert(s.IsIOError());
return s;
}
// Check for the IDENTITY file and create it if not there
s = env_->FileExists(IdentityFileName(dbname_));
if (s.IsNotFound()) {
s = SetIdentityFile(env_, dbname_);
if (!s.ok()) {
return s;
}
} else if (!s.ok()) {
assert(s.IsIOError());
return s;
}
}
Status s = versions_->Recover(column_families, read_only);
if (db_options_.paranoid_checks && s.ok()) {
s = CheckConsistency();
}
if (s.ok()) {
SequenceNumber max_sequence(kMaxSequenceNumber);
default_cf_handle_ = new ColumnFamilyHandleImpl(
versions_->GetColumnFamilySet()->GetDefault(), this, &mutex_);
default_cf_internal_stats_ = default_cf_handle_->cfd()->internal_stats();
single_column_family_mode_ =
versions_->GetColumnFamilySet()->NumberOfColumnFamilies() == 1;
// Recover from all newer log files than the ones named in the
// descriptor (new log files may have been added by the previous
// incarnation without registering them in the descriptor).
//
// Note that prev_log_number() is no longer used, but we pay
// attention to it in case we are recovering a database
// produced by an older version of rocksdb.
const uint64_t min_log = versions_->MinLogNumber();
const uint64_t prev_log = versions_->prev_log_number();
std::vector<std::string> filenames;
s = env_->GetChildren(db_options_.wal_dir, &filenames);
if (!s.ok()) {
return s;
}
std::vector<uint64_t> logs;
for (size_t i = 0; i < filenames.size(); i++) {
uint64_t number;
FileType type;
if (ParseFileName(filenames[i], &number, &type) && type == kLogFile) {
if (is_new_db) {
return Status::Corruption(
"While creating a new Db, wal_dir contains "
"existing log file: ",
filenames[i]);
} else if ((number >= min_log) || (number == prev_log)) {
logs.push_back(number);
}
}
}
if (logs.size() > 0 && error_if_log_file_exist) {
return Status::Corruption(""
"The db was opened in readonly mode with error_if_log_file_exist"
"flag but a log file already exists");
}
if (!logs.empty()) {
// Recover in the order in which the logs were generated
std::sort(logs.begin(), logs.end());
s = RecoverLogFiles(logs, &max_sequence, read_only);
if (!s.ok()) {
// Clear memtables if recovery failed
for (auto cfd : *versions_->GetColumnFamilySet()) {
cfd->CreateNewMemtable(*cfd->GetLatestMutableCFOptions(),
kMaxSequenceNumber);
}
}
}
SetTickerCount(stats_, SEQUENCE_NUMBER, versions_->LastSequence());
}
// Initial value
max_total_in_memory_state_ = 0;
for (auto cfd : *versions_->GetColumnFamilySet()) {
auto* mutable_cf_options = cfd->GetLatestMutableCFOptions();
max_total_in_memory_state_ += mutable_cf_options->write_buffer_size *
mutable_cf_options->max_write_buffer_number;
}
return s;
}
// REQUIRES: log_numbers are sorted in ascending order
Status DBImpl::RecoverLogFiles(const std::vector<uint64_t>& log_numbers,
SequenceNumber* max_sequence, bool read_only) {
struct LogReporter : public log::Reader::Reporter {
Env* env;
Logger* info_log;
const char* fname;
Status* status; // nullptr if db_options_.paranoid_checks==false
virtual void Corruption(size_t bytes, const Status& s) override {
Log(InfoLogLevel::WARN_LEVEL,
info_log, "%s%s: dropping %d bytes; %s",
(this->status == nullptr ? "(ignoring error) " : ""),
fname, static_cast<int>(bytes), s.ToString().c_str());
if (this->status != nullptr && this->status->ok()) {
*this->status = s;
}
}
};
mutex_.AssertHeld();
Status status;
std::unordered_map<int, VersionEdit> version_edits;
// no need to refcount because iteration is under mutex
for (auto cfd : *versions_->GetColumnFamilySet()) {
VersionEdit edit;
edit.SetColumnFamily(cfd->GetID());
version_edits.insert({cfd->GetID(), edit});
}
int job_id = next_job_id_.fetch_add(1);
{
auto stream = event_logger_.Log();
stream << "job" << job_id << "event"
<< "recovery_started";
stream << "log_files";
stream.StartArray();
for (auto log_number : log_numbers) {
stream << log_number;
}
stream.EndArray();
}
bool continue_replay_log = true;
for (auto log_number : log_numbers) {
// The previous incarnation may not have written any MANIFEST
// records after allocating this log number. So we manually
// update the file number allocation counter in VersionSet.
versions_->MarkFileNumberUsedDuringRecovery(log_number);
// Open the log file
std::string fname = LogFileName(db_options_.wal_dir, log_number);
unique_ptr<SequentialFileReader> file_reader;
{
unique_ptr<SequentialFile> file;
status = env_->NewSequentialFile(fname, &file, env_options_);
if (!status.ok()) {
MaybeIgnoreError(&status);
if (!status.ok()) {
return status;
} else {
// Fail with one log file, but that's ok.
// Try next one.
continue;
}
}
file_reader.reset(new SequentialFileReader(std::move(file)));
}
// Create the log reader.
LogReporter reporter;
reporter.env = env_;
reporter.info_log = db_options_.info_log.get();
reporter.fname = fname.c_str();
if (!db_options_.paranoid_checks ||
db_options_.wal_recovery_mode ==
WALRecoveryMode::kSkipAnyCorruptedRecords) {
reporter.status = nullptr;
} else {
reporter.status = &status;
}
// We intentially make log::Reader do checksumming even if
// paranoid_checks==false so that corruptions cause entire commits
// to be skipped instead of propagating bad information (like overly
// large sequence numbers).
log::Reader reader(db_options_.info_log, std::move(file_reader), &reporter,
true /*checksum*/, 0 /*initial_offset*/, log_number);
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"Recovering log #%" PRIu64 " mode %d skip-recovery %d", log_number,
db_options_.wal_recovery_mode, !continue_replay_log);
// Determine if we should tolerate incomplete records at the tail end of the
// Read all the records and add to a memtable
std::string scratch;
Slice record;
WriteBatch batch;
if (!continue_replay_log) {
uint64_t bytes;
if (env_->GetFileSize(fname, &bytes).ok()) {
auto info_log = db_options_.info_log.get();
Log(InfoLogLevel::WARN_LEVEL, info_log, "%s: dropping %d bytes",
fname.c_str(), static_cast<int>(bytes));
}
}
while (
continue_replay_log &&
reader.ReadRecord(&record, &scratch, db_options_.wal_recovery_mode) &&
status.ok()) {
if (record.size() < 12) {
reporter.Corruption(record.size(),
Status::Corruption("log record too small"));
continue;
}
WriteBatchInternal::SetContents(&batch, record);
#ifndef ROCKSDB_LITE
if (db_options_.wal_filter != nullptr) {
WriteBatch new_batch;
bool batch_changed = false;
WalFilter::WalProcessingOption wal_processing_option =
db_options_.wal_filter->LogRecord(batch, &new_batch,
&batch_changed);
switch (wal_processing_option) {
case WalFilter::WalProcessingOption::kContinueProcessing:
// do nothing, proceeed normally
break;
case WalFilter::WalProcessingOption::kIgnoreCurrentRecord:
// skip current record
continue;
case WalFilter::WalProcessingOption::kStopReplay:
// skip current record and stop replay
continue_replay_log = false;
continue;
case WalFilter::WalProcessingOption::kCorruptedRecord: {
status = Status::Corruption("Corruption reported by Wal Filter ",
db_options_.wal_filter->Name());
MaybeIgnoreError(&status);
if (!status.ok()) {
reporter.Corruption(record.size(), status);
continue;
}
break;
}
default: {
assert(false); // unhandled case
status = Status::NotSupported(
"Unknown WalProcessingOption returned"
" by Wal Filter ",
db_options_.wal_filter->Name());
MaybeIgnoreError(&status);
if (!status.ok()) {
return status;
} else {
// Ignore the error with current record processing.
continue;
}
}
}
if (batch_changed) {
// Make sure that the count in the new batch is
// within the orignal count.
int new_count = WriteBatchInternal::Count(&new_batch);
int original_count = WriteBatchInternal::Count(&batch);
if (new_count > original_count) {
Log(InfoLogLevel::FATAL_LEVEL, db_options_.info_log,
"Recovering log #%" PRIu64
" mode %d log filter %s returned "
"more records (%d) than original (%d) which is not allowed. "
"Aborting recovery.",
log_number, db_options_.wal_recovery_mode,
db_options_.wal_filter->Name(), new_count, original_count);
status = Status::NotSupported(
"More than original # of records "
"returned by Wal Filter ",
db_options_.wal_filter->Name());
return status;
}
// Set the same sequence number in the new_batch
// as the original batch.
WriteBatchInternal::SetSequence(&new_batch,
WriteBatchInternal::Sequence(&batch));
batch = new_batch;
}
}
#endif // ROCKSDB_LITE
// If column family was not found, it might mean that the WAL write
// batch references to the column family that was dropped after the
// insert. We don't want to fail the whole write batch in that case --
// we just ignore the update.
// That's why we set ignore missing column families to true
status =
WriteBatchInternal::InsertInto(&batch, column_family_memtables_.get(),
&flush_scheduler_, true, log_number);
MaybeIgnoreError(&status);
if (!status.ok()) {
// We are treating this as a failure while reading since we read valid
// blocks that do not form coherent data
reporter.Corruption(record.size(), status);
continue;
}
const SequenceNumber last_seq = WriteBatchInternal::Sequence(&batch) +
WriteBatchInternal::Count(&batch) - 1;
if ((*max_sequence == kMaxSequenceNumber) || (last_seq > *max_sequence)) {
*max_sequence = last_seq;
}
if (!read_only) {
// we can do this because this is called before client has access to the
// DB and there is only a single thread operating on DB
ColumnFamilyData* cfd;
while ((cfd = flush_scheduler_.TakeNextColumnFamily()) != nullptr) {
cfd->Unref();
// If this asserts, it means that InsertInto failed in
// filtering updates to already-flushed column families
assert(cfd->GetLogNumber() <= log_number);
auto iter = version_edits.find(cfd->GetID());
assert(iter != version_edits.end());
VersionEdit* edit = &iter->second;
status = WriteLevel0TableForRecovery(job_id, cfd, cfd->mem(), edit);
if (!status.ok()) {
// Reflect errors immediately so that conditions like full
// file-systems cause the DB::Open() to fail.
return status;
}
cfd->CreateNewMemtable(*cfd->GetLatestMutableCFOptions(),
*max_sequence);
}
}
}
if (!status.ok()) {
if (db_options_.wal_recovery_mode ==
WALRecoveryMode::kSkipAnyCorruptedRecords) {
// We should ignore all errors unconditionally
status = Status::OK();
} else if (db_options_.wal_recovery_mode ==
WALRecoveryMode::kPointInTimeRecovery) {
// We should ignore the error but not continue replaying
status = Status::OK();
continue_replay_log = false;
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"Point in time recovered to log #%" PRIu64 " seq #%" PRIu64,
log_number, *max_sequence);
} else {
assert(db_options_.wal_recovery_mode ==
WALRecoveryMode::kTolerateCorruptedTailRecords
|| db_options_.wal_recovery_mode ==
WALRecoveryMode::kAbsoluteConsistency);
return status;
}
}
flush_scheduler_.Clear();
if ((*max_sequence != kMaxSequenceNumber) &&
(versions_->LastSequence() < *max_sequence)) {
versions_->SetLastSequence(*max_sequence);
}
}
if (!read_only) {
// no need to refcount since client still doesn't have access
// to the DB and can not drop column families while we iterate
auto max_log_number = log_numbers.back();
for (auto cfd : *versions_->GetColumnFamilySet()) {
auto iter = version_edits.find(cfd->GetID());
assert(iter != version_edits.end());
VersionEdit* edit = &iter->second;
if (cfd->GetLogNumber() > max_log_number) {
// Column family cfd has already flushed the data
// from all logs. Memtable has to be empty because
// we filter the updates based on log_number
// (in WriteBatch::InsertInto)
assert(cfd->mem()->GetFirstSequenceNumber() == 0);
assert(edit->NumEntries() == 0);
continue;
}
// flush the final memtable (if non-empty)
if (cfd->mem()->GetFirstSequenceNumber() != 0) {
status = WriteLevel0TableForRecovery(job_id, cfd, cfd->mem(), edit);
if (!status.ok()) {
// Recovery failed
break;
}
cfd->CreateNewMemtable(*cfd->GetLatestMutableCFOptions(),
*max_sequence);
}
// write MANIFEST with update
// writing log_number in the manifest means that any log file
// with number strongly less than (log_number + 1) is already
// recovered and should be ignored on next reincarnation.
// Since we already recovered max_log_number, we want all logs
// with numbers `<= max_log_number` (includes this one) to be ignored
edit->SetLogNumber(max_log_number + 1);
// we must mark the next log number as used, even though it's
// not actually used. that is because VersionSet assumes
// VersionSet::next_file_number_ always to be strictly greater than any
// log number
versions_->MarkFileNumberUsedDuringRecovery(max_log_number + 1);
status = versions_->LogAndApply(
cfd, *cfd->GetLatestMutableCFOptions(), edit, &mutex_);
if (!status.ok()) {
// Recovery failed
break;
}
}
}
event_logger_.Log() << "job" << job_id << "event"
<< "recovery_finished";
return status;
}
Status DBImpl::WriteLevel0TableForRecovery(int job_id, ColumnFamilyData* cfd,
MemTable* mem, VersionEdit* edit) {
mutex_.AssertHeld();
const uint64_t start_micros = env_->NowMicros();
FileMetaData meta;
meta.fd = FileDescriptor(versions_->NewFileNumber(), 0, 0);
auto pending_outputs_inserted_elem =
CaptureCurrentFileNumberInPendingOutputs();
ReadOptions ro;
ro.total_order_seek = true;
Arena arena;
Status s;
TableProperties table_properties;
{
ScopedArenaIterator iter(mem->NewIterator(ro, &arena));
Log(InfoLogLevel::DEBUG_LEVEL, db_options_.info_log,
"[%s] [WriteLevel0TableForRecovery]"
" Level-0 table #%" PRIu64 ": started",
cfd->GetName().c_str(), meta.fd.GetNumber());
bool paranoid_file_checks =
cfd->GetLatestMutableCFOptions()->paranoid_file_checks;
{
mutex_.Unlock();
TableFileCreationInfo info;
SequenceNumber earliest_write_conflict_snapshot;
std::vector<SequenceNumber> snapshot_seqs =
snapshots_.GetAll(&earliest_write_conflict_snapshot);
s = BuildTable(
dbname_, env_, *cfd->ioptions(), env_options_, cfd->table_cache(),
iter.get(), &meta, cfd->internal_comparator(),
cfd->int_tbl_prop_collector_factories(), cfd->GetID(), snapshot_seqs,
earliest_write_conflict_snapshot,
GetCompressionFlush(*cfd->ioptions()),
cfd->ioptions()->compression_opts, paranoid_file_checks,
cfd->internal_stats(), Env::IO_HIGH, &info.table_properties);
LogFlush(db_options_.info_log);
Log(InfoLogLevel::DEBUG_LEVEL, db_options_.info_log,
"[%s] [WriteLevel0TableForRecovery]"
" Level-0 table #%" PRIu64 ": %" PRIu64 " bytes %s",
cfd->GetName().c_str(), meta.fd.GetNumber(), meta.fd.GetFileSize(),
s.ToString().c_str());
// output to event logger
if (s.ok()) {
info.db_name = dbname_;
info.cf_name = cfd->GetName();
info.file_path = TableFileName(db_options_.db_paths,
meta.fd.GetNumber(),
meta.fd.GetPathId());
info.file_size = meta.fd.GetFileSize();
info.job_id = job_id;
EventHelpers::LogAndNotifyTableFileCreation(
&event_logger_, db_options_.listeners, meta.fd, info);
}
mutex_.Lock();
}
}
ReleaseFileNumberFromPendingOutputs(pending_outputs_inserted_elem);
// Note that if file_size is zero, the file has been deleted and
// should not be added to the manifest.
int level = 0;
if (s.ok() && meta.fd.GetFileSize() > 0) {
edit->AddFile(level, meta.fd.GetNumber(), meta.fd.GetPathId(),
meta.fd.GetFileSize(), meta.smallest, meta.largest,
meta.smallest_seqno, meta.largest_seqno,
meta.marked_for_compaction);
}
InternalStats::CompactionStats stats(1);
stats.micros = env_->NowMicros() - start_micros;
stats.bytes_written = meta.fd.GetFileSize();
stats.num_output_files = 1;
cfd->internal_stats()->AddCompactionStats(level, stats);
cfd->internal_stats()->AddCFStats(
InternalStats::BYTES_FLUSHED, meta.fd.GetFileSize());
RecordTick(stats_, COMPACT_WRITE_BYTES, meta.fd.GetFileSize());
return s;
}
Status DBImpl::FlushMemTableToOutputFile(
ColumnFamilyData* cfd, const MutableCFOptions& mutable_cf_options,
bool* made_progress, JobContext* job_context, LogBuffer* log_buffer) {
mutex_.AssertHeld();
assert(cfd->imm()->NumNotFlushed() != 0);
assert(cfd->imm()->IsFlushPending());
SequenceNumber earliest_write_conflict_snapshot;
std::vector<SequenceNumber> snapshot_seqs =
snapshots_.GetAll(&earliest_write_conflict_snapshot);
FlushJob flush_job(
dbname_, cfd, db_options_, mutable_cf_options, env_options_,
versions_.get(), &mutex_, &shutting_down_, snapshot_seqs,
earliest_write_conflict_snapshot, job_context, log_buffer,
directories_.GetDbDir(), directories_.GetDataDir(0U),
GetCompressionFlush(*cfd->ioptions()), stats_, &event_logger_);
FileMetaData file_meta;
// Within flush_job.Run, rocksdb may call event listener to notify
// file creation and deletion.
//
// Note that flush_job.Run will unlock and lock the db_mutex,
// and EventListener callback will be called when the db_mutex
// is unlocked by the current thread.
Status s = flush_job.Run(&file_meta);
if (s.ok()) {
InstallSuperVersionAndScheduleWorkWrapper(cfd, job_context,
mutable_cf_options);
if (made_progress) {
*made_progress = 1;
}
VersionStorageInfo::LevelSummaryStorage tmp;
LogToBuffer(log_buffer, "[%s] Level summary: %s\n", cfd->GetName().c_str(),
cfd->current()->storage_info()->LevelSummary(&tmp));
}
if (!s.ok() && !s.IsShutdownInProgress() && db_options_.paranoid_checks &&
bg_error_.ok()) {
// if a bad error happened (not ShutdownInProgress) and paranoid_checks is
// true, mark DB read-only
bg_error_ = s;
}
RecordFlushIOStats();
#ifndef ROCKSDB_LITE
if (s.ok()) {
// may temporarily unlock and lock the mutex.
NotifyOnFlushCompleted(cfd, &file_meta, mutable_cf_options,
job_context->job_id, flush_job.GetTableProperties());
}
#endif // ROCKSDB_LITE
return s;
}
void DBImpl::NotifyOnFlushCompleted(ColumnFamilyData* cfd,
FileMetaData* file_meta,
const MutableCFOptions& mutable_cf_options,
int job_id, TableProperties prop) {
#ifndef ROCKSDB_LITE
if (db_options_.listeners.size() == 0U) {
return;
}
mutex_.AssertHeld();
if (shutting_down_.load(std::memory_order_acquire)) {
return;
}
bool triggered_writes_slowdown =
(cfd->current()->storage_info()->NumLevelFiles(0) >=
mutable_cf_options.level0_slowdown_writes_trigger);
bool triggered_writes_stop =
(cfd->current()->storage_info()->NumLevelFiles(0) >=
mutable_cf_options.level0_stop_writes_trigger);
// release lock while notifying events
mutex_.Unlock();
{
FlushJobInfo info;
info.cf_name = cfd->GetName();
// TODO(yhchiang): make db_paths dynamic in case flush does not
// go to L0 in the future.
info.file_path = MakeTableFileName(db_options_.db_paths[0].path,
file_meta->fd.GetNumber());
info.thread_id = env_->GetThreadID();
info.job_id = job_id;
info.triggered_writes_slowdown = triggered_writes_slowdown;
info.triggered_writes_stop = triggered_writes_stop;
info.smallest_seqno = file_meta->smallest_seqno;
info.largest_seqno = file_meta->largest_seqno;
info.table_properties = prop;
for (auto listener : db_options_.listeners) {
listener->OnFlushCompleted(this, info);
}
}
mutex_.Lock();
// no need to signal bg_cv_ as it will be signaled at the end of the
// flush process.
#endif // ROCKSDB_LITE
}
Status DBImpl::CompactRange(const CompactRangeOptions& options,
ColumnFamilyHandle* column_family,
const Slice* begin, const Slice* end) {
if (options.target_path_id >= db_options_.db_paths.size()) {
return Status::InvalidArgument("Invalid target path ID");
}
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
bool exclusive = options.exclusive_manual_compaction;
Status s = FlushMemTable(cfd, FlushOptions());
if (!s.ok()) {
LogFlush(db_options_.info_log);
return s;
}
int max_level_with_files = 0;
{
InstrumentedMutexLock l(&mutex_);
Version* base = cfd->current();
for (int level = 1; level < base->storage_info()->num_non_empty_levels();
level++) {
if (base->storage_info()->OverlapInLevel(level, begin, end)) {
max_level_with_files = level;
}
}
}
int final_output_level = 0;
if (cfd->ioptions()->compaction_style == kCompactionStyleUniversal &&
cfd->NumberLevels() > 1) {
// Always compact all files together.
s = RunManualCompaction(cfd, ColumnFamilyData::kCompactAllLevels,
cfd->NumberLevels() - 1, options.target_path_id,
begin, end, exclusive);
final_output_level = cfd->NumberLevels() - 1;
} else {
for (int level = 0; level <= max_level_with_files; level++) {
int output_level;
// in case the compaction is universal or if we're compacting the
// bottom-most level, the output level will be the same as input one.
// level 0 can never be the bottommost level (i.e. if all files are in
// level 0, we will compact to level 1)
if (cfd->ioptions()->compaction_style == kCompactionStyleUniversal ||
cfd->ioptions()->compaction_style == kCompactionStyleFIFO) {
output_level = level;
} else if (level == max_level_with_files && level > 0) {
if (options.bottommost_level_compaction ==
BottommostLevelCompaction::kSkip) {
// Skip bottommost level compaction
continue;
} else if (options.bottommost_level_compaction ==
BottommostLevelCompaction::kIfHaveCompactionFilter &&
cfd->ioptions()->compaction_filter == nullptr &&
cfd->ioptions()->compaction_filter_factory == nullptr) {
// Skip bottommost level compaction since we don't have a compaction
// filter
continue;
}
output_level = level;
} else {
output_level = level + 1;
if (cfd->ioptions()->compaction_style == kCompactionStyleLevel &&
cfd->ioptions()->level_compaction_dynamic_level_bytes &&
level == 0) {
output_level = ColumnFamilyData::kCompactToBaseLevel;
}
}
s = RunManualCompaction(cfd, level, output_level, options.target_path_id,
begin, end, exclusive);
if (!s.ok()) {
break;
}
if (output_level == ColumnFamilyData::kCompactToBaseLevel) {
final_output_level = cfd->NumberLevels() - 1;
} else if (output_level > final_output_level) {
final_output_level = output_level;
}
TEST_SYNC_POINT("DBImpl::RunManualCompaction()::1");
TEST_SYNC_POINT("DBImpl::RunManualCompaction()::2");
}
}
if (!s.ok()) {
LogFlush(db_options_.info_log);
return s;
}
if (options.change_level) {
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"[RefitLevel] waiting for background threads to stop");
s = PauseBackgroundWork();
if (s.ok()) {
s = ReFitLevel(cfd, final_output_level, options.target_level);
}
ContinueBackgroundWork();
}
LogFlush(db_options_.info_log);
{
InstrumentedMutexLock l(&mutex_);
// an automatic compaction that has been scheduled might have been
// preempted by the manual compactions. Need to schedule it back.
MaybeScheduleFlushOrCompaction();
}
return s;
}
Status DBImpl::CompactFiles(
const CompactionOptions& compact_options,
ColumnFamilyHandle* column_family,
const std::vector<std::string>& input_file_names,
const int output_level, const int output_path_id) {
#ifdef ROCKSDB_LITE
// not supported in lite version
return Status::NotSupported("Not supported in ROCKSDB LITE");
#else
if (column_family == nullptr) {
return Status::InvalidArgument("ColumnFamilyHandle must be non-null.");
}
auto cfd = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family)->cfd();
assert(cfd);
Status s;
JobContext job_context(0, true);
LogBuffer log_buffer(InfoLogLevel::INFO_LEVEL,
db_options_.info_log.get());
// Perform CompactFiles
SuperVersion* sv = GetAndRefSuperVersion(cfd);
{
InstrumentedMutexLock l(&mutex_);
s = CompactFilesImpl(compact_options, cfd, sv->current,
input_file_names, output_level,
output_path_id, &job_context, &log_buffer);
}
ReturnAndCleanupSuperVersion(cfd, sv);
// Find and delete obsolete files
{
InstrumentedMutexLock l(&mutex_);
// If !s.ok(), this means that Compaction failed. In that case, we want
// to delete all obsolete files we might have created and we force
// FindObsoleteFiles(). This is because job_context does not
// catch all created files if compaction failed.
FindObsoleteFiles(&job_context, !s.ok());
} // release the mutex
// delete unnecessary files if any, this is done outside the mutex
if (job_context.HaveSomethingToDelete() || !log_buffer.IsEmpty()) {
// Have to flush the info logs before bg_compaction_scheduled_--
// because if bg_flush_scheduled_ becomes 0 and the lock is
// released, the deconstructor of DB can kick in and destroy all the
// states of DB so info_log might not be available after that point.
// It also applies to access other states that DB owns.
log_buffer.FlushBufferToLog();
if (job_context.HaveSomethingToDelete()) {
// no mutex is locked here. No need to Unlock() and Lock() here.
PurgeObsoleteFiles(job_context);
}
job_context.Clean();
}
return s;
#endif // ROCKSDB_LITE
}
#ifndef ROCKSDB_LITE
Status DBImpl::CompactFilesImpl(
const CompactionOptions& compact_options, ColumnFamilyData* cfd,
Version* version, const std::vector<std::string>& input_file_names,
const int output_level, int output_path_id, JobContext* job_context,
LogBuffer* log_buffer) {
mutex_.AssertHeld();
if (shutting_down_.load(std::memory_order_acquire)) {
return Status::ShutdownInProgress();
}
std::unordered_set<uint64_t> input_set;
for (auto file_name : input_file_names) {
input_set.insert(TableFileNameToNumber(file_name));
}
ColumnFamilyMetaData cf_meta;
// TODO(yhchiang): can directly use version here if none of the
// following functions call is pluggable to external developers.
version->GetColumnFamilyMetaData(&cf_meta);
if (output_path_id < 0) {
if (db_options_.db_paths.size() == 1U) {
output_path_id = 0;
} else {
return Status::NotSupported(
"Automatic output path selection is not "
"yet supported in CompactFiles()");
}
}
Status s = cfd->compaction_picker()->SanitizeCompactionInputFiles(
&input_set, cf_meta, output_level);
if (!s.ok()) {
return s;
}
std::vector<CompactionInputFiles> input_files;
s = cfd->compaction_picker()->GetCompactionInputsFromFileNumbers(
&input_files, &input_set, version->storage_info(), compact_options);
if (!s.ok()) {
return s;
}
for (auto inputs : input_files) {
if (cfd->compaction_picker()->FilesInCompaction(inputs.files)) {
return Status::Aborted(
"Some of the necessary compaction input "
"files are already being compacted");
}
}
// At this point, CompactFiles will be run.
bg_compaction_scheduled_++;
unique_ptr<Compaction> c;
assert(cfd->compaction_picker());
c.reset(cfd->compaction_picker()->FormCompaction(
compact_options, input_files, output_level, version->storage_info(),
*cfd->GetLatestMutableCFOptions(), output_path_id));
if (!c) {
return Status::Aborted("Another Level 0 compaction is running");
}
c->SetInputVersion(version);
// deletion compaction currently not allowed in CompactFiles.
assert(!c->deletion_compaction());
SequenceNumber earliest_write_conflict_snapshot;
std::vector<SequenceNumber> snapshot_seqs =
snapshots_.GetAll(&earliest_write_conflict_snapshot);
assert(is_snapshot_supported_ || snapshots_.empty());
CompactionJob compaction_job(
job_context->job_id, c.get(), db_options_, env_options_, versions_.get(),
&shutting_down_, log_buffer, directories_.GetDbDir(),
directories_.GetDataDir(c->output_path_id()), stats_, snapshot_seqs,
earliest_write_conflict_snapshot, table_cache_, &event_logger_,
c->mutable_cf_options()->paranoid_file_checks,
c->mutable_cf_options()->compaction_measure_io_stats, dbname_,
nullptr); // Here we pass a nullptr for CompactionJobStats because
// CompactFiles does not trigger OnCompactionCompleted(),
// which is the only place where CompactionJobStats is
// returned. The idea of not triggering OnCompationCompleted()
// is that CompactFiles runs in the caller thread, so the user
// should always know when it completes. As a result, it makes
// less sense to notify the users something they should already
// know.
//
// In the future, if we would like to add CompactionJobStats
// support for CompactFiles, we should have CompactFiles API
// pass a pointer of CompactionJobStats as the out-value
// instead of using EventListener.
compaction_job.Prepare();
mutex_.Unlock();
TEST_SYNC_POINT("CompactFilesImpl:0");
TEST_SYNC_POINT("CompactFilesImpl:1");
compaction_job.Run();
mutex_.Lock();
Status status = compaction_job.Install(*c->mutable_cf_options(), &mutex_);
if (status.ok()) {
InstallSuperVersionAndScheduleWorkWrapper(
c->column_family_data(), job_context, *c->mutable_cf_options());
}
c->ReleaseCompactionFiles(s);
c.reset();
if (status.ok()) {
// Done
} else if (status.IsShutdownInProgress()) {
// Ignore compaction errors found during shutting down
} else {
Log(InfoLogLevel::WARN_LEVEL, db_options_.info_log,
"[%s] [JOB %d] Compaction error: %s",
c->column_family_data()->GetName().c_str(), job_context->job_id,
status.ToString().c_str());
if (db_options_.paranoid_checks && bg_error_.ok()) {
bg_error_ = status;
}
}
bg_compaction_scheduled_--;
if (bg_compaction_scheduled_ == 0) {
bg_cv_.SignalAll();
}
return status;
}
#endif // ROCKSDB_LITE
Status DBImpl::PauseBackgroundWork() {
InstrumentedMutexLock guard_lock(&mutex_);
bg_work_paused_++;
while (bg_compaction_scheduled_ > 0 || bg_flush_scheduled_ > 0) {
bg_cv_.Wait();
}
return Status::OK();
}
Status DBImpl::ContinueBackgroundWork() {
InstrumentedMutexLock guard_lock(&mutex_);
if (bg_work_paused_ == 0) {
return Status::InvalidArgument();
}
assert(bg_work_paused_ > 0);
bg_work_paused_--;
if (bg_work_paused_ == 0) {
MaybeScheduleFlushOrCompaction();
}
return Status::OK();
}
void DBImpl::NotifyOnCompactionCompleted(
ColumnFamilyData* cfd, Compaction *c, const Status &st,
const CompactionJobStats& compaction_job_stats,
const int job_id) {
#ifndef ROCKSDB_LITE
if (db_options_.listeners.size() == 0U) {
return;
}
mutex_.AssertHeld();
if (shutting_down_.load(std::memory_order_acquire)) {
return;
}
// release lock while notifying events
mutex_.Unlock();
{
CompactionJobInfo info;
info.cf_name = cfd->GetName();
info.status = st;
info.thread_id = env_->GetThreadID();
info.job_id = job_id;
info.base_input_level = c->start_level();
info.output_level = c->output_level();
info.stats = compaction_job_stats;
info.table_properties = c->GetOutputTableProperties();
info.compaction_reason = c->compaction_reason();
for (size_t i = 0; i < c->num_input_levels(); ++i) {
for (const auto fmd : *c->inputs(i)) {
auto fn = TableFileName(db_options_.db_paths, fmd->fd.GetNumber(),
fmd->fd.GetPathId());
info.input_files.push_back(fn);
if (info.table_properties.count(fn) == 0) {
std::shared_ptr<const TableProperties> tp;
auto s = cfd->current()->GetTableProperties(&tp, fmd, &fn);
if (s.ok()) {
info.table_properties[fn] = tp;
}
}
}
}
for (const auto newf : c->edit()->GetNewFiles()) {
info.output_files.push_back(
TableFileName(db_options_.db_paths,
newf.second.fd.GetNumber(),
newf.second.fd.GetPathId()));
}
for (auto listener : db_options_.listeners) {
listener->OnCompactionCompleted(this, info);
}
}
mutex_.Lock();
// no need to signal bg_cv_ as it will be signaled at the end of the
// flush process.
#endif // ROCKSDB_LITE
}
Status DBImpl::SetOptions(ColumnFamilyHandle* column_family,
const std::unordered_map<std::string, std::string>& options_map) {
#ifdef ROCKSDB_LITE
return Status::NotSupported("Not supported in ROCKSDB LITE");
#else
auto* cfd = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family)->cfd();
if (options_map.empty()) {
Log(InfoLogLevel::WARN_LEVEL,
db_options_.info_log, "SetOptions() on column family [%s], empty input",
cfd->GetName().c_str());
return Status::InvalidArgument("empty input");
}
MutableCFOptions new_options;
Status s;
Status persist_options_status;
{
InstrumentedMutexLock l(&mutex_);
s = cfd->SetOptions(options_map);
if (s.ok()) {
new_options = *cfd->GetLatestMutableCFOptions();
}
if (s.ok()) {
// Persist RocksDB options under the single write thread
WriteThread::Writer w;
write_thread_.EnterUnbatched(&w, &mutex_);
persist_options_status = WriteOptionsFile();
write_thread_.ExitUnbatched(&w);
}
}
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"SetOptions() on column family [%s], inputs:",
cfd->GetName().c_str());
for (const auto& o : options_map) {
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"%s: %s\n", o.first.c_str(), o.second.c_str());
}
if (s.ok()) {
Log(InfoLogLevel::INFO_LEVEL,
db_options_.info_log, "[%s] SetOptions succeeded",
cfd->GetName().c_str());
new_options.Dump(db_options_.info_log.get());
if (!persist_options_status.ok()) {
if (db_options_.fail_if_options_file_error) {
s = Status::IOError(
"SetOptions succeeded, but unable to persist options",
persist_options_status.ToString());
}
Warn(db_options_.info_log,
"Unable to persist options in SetOptions() -- %s",
persist_options_status.ToString().c_str());
}
} else {
Log(InfoLogLevel::WARN_LEVEL, db_options_.info_log,
"[%s] SetOptions failed", cfd->GetName().c_str());
}
LogFlush(db_options_.info_log);
return s;
#endif // ROCKSDB_LITE
}
// return the same level if it cannot be moved
int DBImpl::FindMinimumEmptyLevelFitting(ColumnFamilyData* cfd,
const MutableCFOptions& mutable_cf_options, int level) {
mutex_.AssertHeld();
const auto* vstorage = cfd->current()->storage_info();
int minimum_level = level;
for (int i = level - 1; i > 0; --i) {
// stop if level i is not empty
if (vstorage->NumLevelFiles(i) > 0) break;
// stop if level i is too small (cannot fit the level files)
if (vstorage->MaxBytesForLevel(i) < vstorage->NumLevelBytes(level)) {
break;
}
minimum_level = i;
}
return minimum_level;
}
// REQUIREMENT: block all background work by calling PauseBackgroundWork()
// before calling this function
Status DBImpl::ReFitLevel(ColumnFamilyData* cfd, int level, int target_level) {
assert(level < cfd->NumberLevels());
if (target_level >= cfd->NumberLevels()) {
return Status::InvalidArgument("Target level exceeds number of levels");
}
std::unique_ptr<SuperVersion> superversion_to_free;
std::unique_ptr<SuperVersion> new_superversion(new SuperVersion());
Status status;
InstrumentedMutexLock guard_lock(&mutex_);
// only allow one thread refitting
if (refitting_level_) {
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"[ReFitLevel] another thread is refitting");
return Status::NotSupported("another thread is refitting");
}
refitting_level_ = true;
const MutableCFOptions mutable_cf_options = *cfd->GetLatestMutableCFOptions();
// move to a smaller level
int to_level = target_level;
if (target_level < 0) {
to_level = FindMinimumEmptyLevelFitting(cfd, mutable_cf_options, level);
}
auto* vstorage = cfd->current()->storage_info();
if (to_level > level) {
if (level == 0) {
return Status::NotSupported(
"Cannot change from level 0 to other levels.");
}
// Check levels are empty for a trivial move
for (int l = level + 1; l <= to_level; l++) {
if (vstorage->NumLevelFiles(l) > 0) {
return Status::NotSupported(
"Levels between source and target are not empty for a move.");
}
}
}
if (to_level != level) {
Log(InfoLogLevel::DEBUG_LEVEL, db_options_.info_log,
"[%s] Before refitting:\n%s", cfd->GetName().c_str(),
cfd->current()->DebugString().data());
VersionEdit edit;
edit.SetColumnFamily(cfd->GetID());
for (const auto& f : vstorage->LevelFiles(level)) {
edit.DeleteFile(level, f->fd.GetNumber());
edit.AddFile(to_level, f->fd.GetNumber(), f->fd.GetPathId(),
f->fd.GetFileSize(), f->smallest, f->largest,
f->smallest_seqno, f->largest_seqno,
f->marked_for_compaction);
}
Log(InfoLogLevel::DEBUG_LEVEL, db_options_.info_log,
"[%s] Apply version edit:\n%s", cfd->GetName().c_str(),
edit.DebugString().data());
status = versions_->LogAndApply(cfd, mutable_cf_options, &edit, &mutex_,
directories_.GetDbDir());
superversion_to_free.reset(InstallSuperVersionAndScheduleWork(
cfd, new_superversion.release(), mutable_cf_options));
Log(InfoLogLevel::DEBUG_LEVEL, db_options_.info_log,
"[%s] LogAndApply: %s\n", cfd->GetName().c_str(),
status.ToString().data());
if (status.ok()) {
Log(InfoLogLevel::DEBUG_LEVEL, db_options_.info_log,
"[%s] After refitting:\n%s", cfd->GetName().c_str(),
cfd->current()->DebugString().data());
}
}
refitting_level_ = false;
return status;
}
int DBImpl::NumberLevels(ColumnFamilyHandle* column_family) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
return cfh->cfd()->NumberLevels();
}
int DBImpl::MaxMemCompactionLevel(ColumnFamilyHandle* column_family) {
return 0;
}
int DBImpl::Level0StopWriteTrigger(ColumnFamilyHandle* column_family) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
InstrumentedMutexLock l(&mutex_);
return cfh->cfd()->GetSuperVersion()->
mutable_cf_options.level0_stop_writes_trigger;
}
Status DBImpl::Flush(const FlushOptions& flush_options,
ColumnFamilyHandle* column_family) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
return FlushMemTable(cfh->cfd(), flush_options);
}
Status DBImpl::SyncWAL() {
autovector<log::Writer*, 1> logs_to_sync;
bool need_log_dir_sync;
uint64_t current_log_number;
{
InstrumentedMutexLock l(&mutex_);
assert(!logs_.empty());
// This SyncWAL() call only cares about logs up to this number.
current_log_number = logfile_number_;
while (logs_.front().number <= current_log_number &&
logs_.front().getting_synced) {
log_sync_cv_.Wait();
}
// First check that logs are safe to sync in background.
for (auto it = logs_.begin();
it != logs_.end() && it->number <= current_log_number; ++it) {
if (!it->writer->file()->writable_file()->IsSyncThreadSafe()) {
return Status::NotSupported(
"SyncWAL() is not supported for this implementation of WAL file",
db_options_.allow_mmap_writes
? "try setting Options::allow_mmap_writes to false"
: Slice());
}
}
for (auto it = logs_.begin();
it != logs_.end() && it->number <= current_log_number; ++it) {
auto& log = *it;
assert(!log.getting_synced);
log.getting_synced = true;
logs_to_sync.push_back(log.writer);
}
need_log_dir_sync = !log_dir_synced_;
}
RecordTick(stats_, WAL_FILE_SYNCED);
Status status;
for (log::Writer* log : logs_to_sync) {
status = log->file()->SyncWithoutFlush(db_options_.use_fsync);
if (!status.ok()) {
break;
}
}
if (status.ok() && need_log_dir_sync) {
status = directories_.GetWalDir()->Fsync();
}
{
InstrumentedMutexLock l(&mutex_);
MarkLogsSynced(current_log_number, need_log_dir_sync, status);
}
return status;
}
void DBImpl::MarkLogsSynced(
uint64_t up_to, bool synced_dir, const Status& status) {
mutex_.AssertHeld();
if (synced_dir &&
logfile_number_ == up_to &&
status.ok()) {
log_dir_synced_ = true;
}
for (auto it = logs_.begin(); it != logs_.end() && it->number <= up_to;) {
auto& log = *it;
assert(log.getting_synced);
if (status.ok() && logs_.size() > 1) {
logs_to_free_.push_back(log.ReleaseWriter());
it = logs_.erase(it);
} else {
log.getting_synced = false;
++it;
}
}
assert(logs_.empty() || (logs_.size() == 1 && !logs_[0].getting_synced));
log_sync_cv_.SignalAll();
}
SequenceNumber DBImpl::GetLatestSequenceNumber() const {
return versions_->LastSequence();
}
Status DBImpl::RunManualCompaction(ColumnFamilyData* cfd, int input_level,
int output_level, uint32_t output_path_id,
const Slice* begin, const Slice* end,
bool exclusive, bool disallow_trivial_move) {
assert(input_level == ColumnFamilyData::kCompactAllLevels ||
input_level >= 0);
InternalKey begin_storage, end_storage;
CompactionArg* ca;
bool scheduled = false;
bool manual_conflict = false;
ManualCompaction manual;
manual.cfd = cfd;
manual.input_level = input_level;
manual.output_level = output_level;
manual.output_path_id = output_path_id;
manual.done = false;
manual.in_progress = false;
manual.incomplete = false;
manual.exclusive = exclusive;
manual.disallow_trivial_move = disallow_trivial_move;
// For universal compaction, we enforce every manual compaction to compact
// all files.
if (begin == nullptr ||
cfd->ioptions()->compaction_style == kCompactionStyleUniversal ||
cfd->ioptions()->compaction_style == kCompactionStyleFIFO) {
manual.begin = nullptr;
} else {
begin_storage.SetMaxPossibleForUserKey(*begin);
manual.begin = &begin_storage;
}
if (end == nullptr ||
cfd->ioptions()->compaction_style == kCompactionStyleUniversal ||
cfd->ioptions()->compaction_style == kCompactionStyleFIFO) {
manual.end = nullptr;
} else {
end_storage.SetMinPossibleForUserKey(*end);
manual.end = &end_storage;
}
InstrumentedMutexLock l(&mutex_);
// When a manual compaction arrives, temporarily disable scheduling of
// non-manual compactions and wait until the number of scheduled compaction
// jobs drops to zero. This is needed to ensure that this manual compaction
// can compact any range of keys/files.
//
// HasPendingManualCompaction() is true when at least one thread is inside
// RunManualCompaction(), i.e. during that time no other compaction will
// get scheduled (see MaybeScheduleFlushOrCompaction).
//
// Note that the following loop doesn't stop more that one thread calling
// RunManualCompaction() from getting to the second while loop below.
// However, only one of them will actually schedule compaction, while
// others will wait on a condition variable until it completes.
AddManualCompaction(&manual);
TEST_SYNC_POINT_CALLBACK("DBImpl::RunManualCompaction:NotScheduled", &mutex_);
if (exclusive) {
while (bg_compaction_scheduled_ > 0) {
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"[%s] Manual compaction waiting for all other scheduled background "
"compactions to finish",
cfd->GetName().c_str());
bg_cv_.Wait();
}
}
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"[%s] Manual compaction starting",
cfd->GetName().c_str());
// We don't check bg_error_ here, because if we get the error in compaction,
// the compaction will set manual.status to bg_error_ and set manual.done to
// true.
while (!manual.done) {
assert(HasPendingManualCompaction());
manual_conflict = false;
if (ShouldntRunManualCompaction(&manual) || (manual.in_progress == true) ||
scheduled ||
((manual.manual_end = &manual.tmp_storage1)&&(
(manual.compaction = manual.cfd->CompactRange(
*manual.cfd->GetLatestMutableCFOptions(), manual.input_level,
manual.output_level, manual.output_path_id, manual.begin,
manual.end, &manual.manual_end, &manual_conflict)) ==
nullptr) &&
manual_conflict)) {
// exclusive manual compactions should not see a conflict during
// CompactRange
assert(!exclusive || !manual_conflict);
// Running either this or some other manual compaction
bg_cv_.Wait();
if (scheduled && manual.incomplete == true) {
assert(!manual.in_progress);
scheduled = false;
manual.incomplete = false;
}
} else if (!scheduled) {
if (manual.compaction == nullptr) {
manual.done = true;
bg_cv_.SignalAll();
continue;
}
ca = new CompactionArg;
ca->db = this;
ca->m = &manual;
manual.incomplete = false;
bg_compaction_scheduled_++;
env_->Schedule(&DBImpl::BGWorkCompaction, ca, Env::Priority::LOW, this,
&DBImpl::UnscheduleCallback);
scheduled = true;
}
}
assert(!manual.in_progress);
assert(HasPendingManualCompaction());
RemoveManualCompaction(&manual);
bg_cv_.SignalAll();
return manual.status;
}
InternalIterator* DBImpl::NewInternalIterator(
Arena* arena, ColumnFamilyHandle* column_family) {
ColumnFamilyData* cfd;
if (column_family == nullptr) {
cfd = default_cf_handle_->cfd();
} else {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
cfd = cfh->cfd();
}
mutex_.Lock();
SuperVersion* super_version = cfd->GetSuperVersion()->Ref();
mutex_.Unlock();
ReadOptions roptions;
return NewInternalIterator(roptions, cfd, super_version, arena);
}
Status DBImpl::FlushMemTable(ColumnFamilyData* cfd,
const FlushOptions& flush_options) {
Status s;
{
WriteContext context;
InstrumentedMutexLock guard_lock(&mutex_);
if (cfd->imm()->NumNotFlushed() == 0 && cfd->mem()->IsEmpty()) {
// Nothing to flush
return Status::OK();
}
WriteThread::Writer w;
write_thread_.EnterUnbatched(&w, &mutex_);
// SwitchMemtable() will release and reacquire mutex
// during execution
s = SwitchMemtable(cfd, &context);
write_thread_.ExitUnbatched(&w);
cfd->imm()->FlushRequested();
// schedule flush
SchedulePendingFlush(cfd);
MaybeScheduleFlushOrCompaction();
}
if (s.ok() && flush_options.wait) {
// Wait until the compaction completes
s = WaitForFlushMemTable(cfd);
}
return s;
}
Status DBImpl::WaitForFlushMemTable(ColumnFamilyData* cfd) {
Status s;
// Wait until the compaction completes
InstrumentedMutexLock l(&mutex_);
while (cfd->imm()->NumNotFlushed() > 0 && bg_error_.ok()) {
if (shutting_down_.load(std::memory_order_acquire)) {
return Status::ShutdownInProgress();
}
bg_cv_.Wait();
}
if (!bg_error_.ok()) {
s = bg_error_;
}
return s;
}
Status DBImpl::EnableAutoCompaction(
const std::vector<ColumnFamilyHandle*>& column_family_handles) {
Status s;
for (auto cf_ptr : column_family_handles) {
Status status =
this->SetOptions(cf_ptr, {{"disable_auto_compactions", "false"}});
if (status.ok()) {
ColumnFamilyData* cfd =
reinterpret_cast<ColumnFamilyHandleImpl*>(cf_ptr)->cfd();
InstrumentedMutexLock guard_lock(&mutex_);
delete this->InstallSuperVersionAndScheduleWork(
cfd, nullptr, *cfd->GetLatestMutableCFOptions());
} else {
s = status;
}
}
return s;
}
void DBImpl::MaybeScheduleFlushOrCompaction() {
mutex_.AssertHeld();
if (!opened_successfully_) {
// Compaction may introduce data race to DB open
return;
}
if (bg_work_paused_ > 0) {
// we paused the background work
return;
} else if (shutting_down_.load(std::memory_order_acquire)) {
// DB is being deleted; no more background compactions
return;
}
while (unscheduled_flushes_ > 0 &&
bg_flush_scheduled_ < db_options_.max_background_flushes) {
unscheduled_flushes_--;
bg_flush_scheduled_++;
env_->Schedule(&DBImpl::BGWorkFlush, this, Env::Priority::HIGH, this);
}
// special case -- if max_background_flushes == 0, then schedule flush on a
// compaction thread
if (db_options_.max_background_flushes == 0) {
while (unscheduled_flushes_ > 0 &&
bg_flush_scheduled_ + bg_compaction_scheduled_ <
db_options_.max_background_compactions) {
unscheduled_flushes_--;
bg_flush_scheduled_++;
env_->Schedule(&DBImpl::BGWorkFlush, this, Env::Priority::LOW, this);
}
}
if (HasExclusiveManualCompaction()) {
// only manual compactions are allowed to run. don't schedule automatic
// compactions
return;
}
while (bg_compaction_scheduled_ < db_options_.max_background_compactions &&
unscheduled_compactions_ > 0) {
CompactionArg* ca = new CompactionArg;
ca->db = this;
ca->m = nullptr;
bg_compaction_scheduled_++;
unscheduled_compactions_--;
env_->Schedule(&DBImpl::BGWorkCompaction, ca, Env::Priority::LOW, this,
&DBImpl::UnscheduleCallback);
}
}
void DBImpl::AddToCompactionQueue(ColumnFamilyData* cfd) {
assert(!cfd->pending_compaction());
cfd->Ref();
compaction_queue_.push_back(cfd);
cfd->set_pending_compaction(true);
}
ColumnFamilyData* DBImpl::PopFirstFromCompactionQueue() {
assert(!compaction_queue_.empty());
auto cfd = *compaction_queue_.begin();
compaction_queue_.pop_front();
assert(cfd->pending_compaction());
cfd->set_pending_compaction(false);
return cfd;
}
void DBImpl::AddToFlushQueue(ColumnFamilyData* cfd) {
assert(!cfd->pending_flush());
cfd->Ref();
flush_queue_.push_back(cfd);
cfd->set_pending_flush(true);
}
ColumnFamilyData* DBImpl::PopFirstFromFlushQueue() {
assert(!flush_queue_.empty());
auto cfd = *flush_queue_.begin();
flush_queue_.pop_front();
assert(cfd->pending_flush());
cfd->set_pending_flush(false);
return cfd;
}
void DBImpl::SchedulePendingFlush(ColumnFamilyData* cfd) {
if (!cfd->pending_flush() && cfd->imm()->IsFlushPending()) {
AddToFlushQueue(cfd);
++unscheduled_flushes_;
}
}
void DBImpl::SchedulePendingCompaction(ColumnFamilyData* cfd) {
if (!cfd->pending_compaction() && cfd->NeedsCompaction()) {
AddToCompactionQueue(cfd);
++unscheduled_compactions_;
}
}
void DBImpl::RecordFlushIOStats() {
RecordTick(stats_, FLUSH_WRITE_BYTES, IOSTATS(bytes_written));
IOSTATS_RESET(bytes_written);
}
void DBImpl::BGWorkFlush(void* db) {
IOSTATS_SET_THREAD_POOL_ID(Env::Priority::HIGH);
TEST_SYNC_POINT("DBImpl::BGWorkFlush");
reinterpret_cast<DBImpl*>(db)->BackgroundCallFlush();
TEST_SYNC_POINT("DBImpl::BGWorkFlush:done");
}
void DBImpl::BGWorkCompaction(void* arg) {
CompactionArg ca = *(reinterpret_cast<CompactionArg*>(arg));
delete reinterpret_cast<CompactionArg*>(arg);
IOSTATS_SET_THREAD_POOL_ID(Env::Priority::LOW);
TEST_SYNC_POINT("DBImpl::BGWorkCompaction");
reinterpret_cast<DBImpl*>(ca.db)->BackgroundCallCompaction(ca.m);
}
void DBImpl::UnscheduleCallback(void* arg) {
CompactionArg ca = *(reinterpret_cast<CompactionArg*>(arg));
delete reinterpret_cast<CompactionArg*>(arg);
if ((ca.m != nullptr) && (ca.m->compaction != nullptr)) {
delete ca.m->compaction;
}
TEST_SYNC_POINT("DBImpl::UnscheduleCallback");
}
Status DBImpl::BackgroundFlush(bool* made_progress, JobContext* job_context,
LogBuffer* log_buffer) {
mutex_.AssertHeld();
Status status = bg_error_;
if (status.ok() && shutting_down_.load(std::memory_order_acquire)) {
status = Status::ShutdownInProgress();
}
if (!status.ok()) {
return status;
}
ColumnFamilyData* cfd = nullptr;
while (!flush_queue_.empty()) {
// This cfd is already referenced
auto first_cfd = PopFirstFromFlushQueue();
if (first_cfd->IsDropped() || !first_cfd->imm()->IsFlushPending()) {
// can't flush this CF, try next one
if (first_cfd->Unref()) {
delete first_cfd;
}
continue;
}
// found a flush!
cfd = first_cfd;
break;
}
if (cfd != nullptr) {
const MutableCFOptions mutable_cf_options =
*cfd->GetLatestMutableCFOptions();
LogToBuffer(
log_buffer,
"Calling FlushMemTableToOutputFile with column "
"family [%s], flush slots available %d, compaction slots available %d",
cfd->GetName().c_str(),
db_options_.max_background_flushes - bg_flush_scheduled_,
db_options_.max_background_compactions - bg_compaction_scheduled_);
status = FlushMemTableToOutputFile(cfd, mutable_cf_options, made_progress,
job_context, log_buffer);
if (cfd->Unref()) {
delete cfd;
}
}
return status;
}
void DBImpl::BackgroundCallFlush() {
bool made_progress = false;
JobContext job_context(next_job_id_.fetch_add(1), true);
assert(bg_flush_scheduled_);
LogBuffer log_buffer(InfoLogLevel::INFO_LEVEL, db_options_.info_log.get());
{
InstrumentedMutexLock l(&mutex_);
num_running_flushes_++;
auto pending_outputs_inserted_elem =
CaptureCurrentFileNumberInPendingOutputs();
Status s = BackgroundFlush(&made_progress, &job_context, &log_buffer);
if (!s.ok() && !s.IsShutdownInProgress()) {
// Wait a little bit before retrying background flush in
// case this is an environmental problem and we do not want to
// chew up resources for failed flushes for the duration of
// the problem.
uint64_t error_cnt =
default_cf_internal_stats_->BumpAndGetBackgroundErrorCount();
bg_cv_.SignalAll(); // In case a waiter can proceed despite the error
mutex_.Unlock();
Log(InfoLogLevel::ERROR_LEVEL, db_options_.info_log,
"Waiting after background flush error: %s"
"Accumulated background error counts: %" PRIu64,
s.ToString().c_str(), error_cnt);
log_buffer.FlushBufferToLog();
LogFlush(db_options_.info_log);
env_->SleepForMicroseconds(1000000);
mutex_.Lock();
}
ReleaseFileNumberFromPendingOutputs(pending_outputs_inserted_elem);
// If flush failed, we want to delete all temporary files that we might have
// created. Thus, we force full scan in FindObsoleteFiles()
FindObsoleteFiles(&job_context, !s.ok() && !s.IsShutdownInProgress());
// delete unnecessary files if any, this is done outside the mutex
if (job_context.HaveSomethingToDelete() || !log_buffer.IsEmpty()) {
mutex_.Unlock();
// Have to flush the info logs before bg_flush_scheduled_--
// because if bg_flush_scheduled_ becomes 0 and the lock is
// released, the deconstructor of DB can kick in and destroy all the
// states of DB so info_log might not be available after that point.
// It also applies to access other states that DB owns.
log_buffer.FlushBufferToLog();
if (job_context.HaveSomethingToDelete()) {
PurgeObsoleteFiles(job_context);
}
job_context.Clean();
mutex_.Lock();
}
assert(num_running_flushes_ > 0);
num_running_flushes_--;
bg_flush_scheduled_--;
// See if there's more work to be done
MaybeScheduleFlushOrCompaction();
RecordFlushIOStats();
bg_cv_.SignalAll();
// IMPORTANT: there should be no code after calling SignalAll. This call may
// signal the DB destructor that it's OK to proceed with destruction. In
// that case, all DB variables will be dealloacated and referencing them
// will cause trouble.
}
}
void DBImpl::BackgroundCallCompaction(void* arg) {
bool made_progress = false;
ManualCompaction* m = reinterpret_cast<ManualCompaction*>(arg);
JobContext job_context(next_job_id_.fetch_add(1), true);
TEST_SYNC_POINT("BackgroundCallCompaction:0");
MaybeDumpStats();
LogBuffer log_buffer(InfoLogLevel::INFO_LEVEL, db_options_.info_log.get());
{
InstrumentedMutexLock l(&mutex_);
num_running_compactions_++;
auto pending_outputs_inserted_elem =
CaptureCurrentFileNumberInPendingOutputs();
assert(bg_compaction_scheduled_);
Status s =
BackgroundCompaction(&made_progress, &job_context, &log_buffer, m);
TEST_SYNC_POINT("BackgroundCallCompaction:1");
if (!s.ok() && !s.IsShutdownInProgress()) {
// Wait a little bit before retrying background compaction in
// case this is an environmental problem and we do not want to
// chew up resources for failed compactions for the duration of
// the problem.
uint64_t error_cnt =
default_cf_internal_stats_->BumpAndGetBackgroundErrorCount();
bg_cv_.SignalAll(); // In case a waiter can proceed despite the error
mutex_.Unlock();
log_buffer.FlushBufferToLog();
Log(InfoLogLevel::ERROR_LEVEL, db_options_.info_log,
"Waiting after background compaction error: %s, "
"Accumulated background error counts: %" PRIu64,
s.ToString().c_str(), error_cnt);
LogFlush(db_options_.info_log);
env_->SleepForMicroseconds(1000000);
mutex_.Lock();
}
ReleaseFileNumberFromPendingOutputs(pending_outputs_inserted_elem);
// If compaction failed, we want to delete all temporary files that we might
// have created (they might not be all recorded in job_context in case of a
// failure). Thus, we force full scan in FindObsoleteFiles()
FindObsoleteFiles(&job_context, !s.ok() && !s.IsShutdownInProgress());
// delete unnecessary files if any, this is done outside the mutex
if (job_context.HaveSomethingToDelete() || !log_buffer.IsEmpty()) {
mutex_.Unlock();
// Have to flush the info logs before bg_compaction_scheduled_--
// because if bg_flush_scheduled_ becomes 0 and the lock is
// released, the deconstructor of DB can kick in and destroy all the
// states of DB so info_log might not be available after that point.
// It also applies to access other states that DB owns.
log_buffer.FlushBufferToLog();
if (job_context.HaveSomethingToDelete()) {
PurgeObsoleteFiles(job_context);
}
job_context.Clean();
mutex_.Lock();
}
assert(num_running_compactions_ > 0);
num_running_compactions_--;
bg_compaction_scheduled_--;
versions_->GetColumnFamilySet()->FreeDeadColumnFamilies();
// See if there's more work to be done
MaybeScheduleFlushOrCompaction();
if (made_progress || bg_compaction_scheduled_ == 0 ||
HasPendingManualCompaction()) {
// signal if
// * made_progress -- need to wakeup DelayWrite
// * bg_compaction_scheduled_ == 0 -- need to wakeup ~DBImpl
// * HasPendingManualCompaction -- need to wakeup RunManualCompaction
// If none of this is true, there is no need to signal since nobody is
// waiting for it
bg_cv_.SignalAll();
}
// IMPORTANT: there should be no code after calling SignalAll. This call may
// signal the DB destructor that it's OK to proceed with destruction. In
// that case, all DB variables will be dealloacated and referencing them
// will cause trouble.
}
}
Status DBImpl::BackgroundCompaction(bool* made_progress,
JobContext* job_context,
LogBuffer* log_buffer, void* arg) {
ManualCompaction* manual_compaction =
reinterpret_cast<ManualCompaction*>(arg);
*made_progress = false;
mutex_.AssertHeld();
bool is_manual = (manual_compaction != nullptr);
// (manual_compaction->in_progress == false);
bool trivial_move_disallowed =
is_manual && manual_compaction->disallow_trivial_move;
CompactionJobStats compaction_job_stats;
Status status = bg_error_;
if (status.ok() && shutting_down_.load(std::memory_order_acquire)) {
status = Status::ShutdownInProgress();
}
if (!status.ok()) {
if (is_manual) {
manual_compaction->status = status;
manual_compaction->done = true;
manual_compaction->in_progress = false;
delete manual_compaction->compaction;
manual_compaction = nullptr;
}
return status;
}
if (is_manual) {
// another thread cannot pick up the same work
manual_compaction->in_progress = true;
}
unique_ptr<Compaction> c;
// InternalKey manual_end_storage;
// InternalKey* manual_end = &manual_end_storage;
if (is_manual) {
ManualCompaction* m = manual_compaction;
assert(m->in_progress);
c.reset(std::move(m->compaction));
if (!c) {
m->done = true;
m->manual_end = nullptr;
LogToBuffer(log_buffer,
"[%s] Manual compaction from level-%d from %s .. "
"%s; nothing to do\n",
m->cfd->GetName().c_str(), m->input_level,
(m->begin ? m->begin->DebugString().c_str() : "(begin)"),
(m->end ? m->end->DebugString().c_str() : "(end)"));
} else {
LogToBuffer(log_buffer,
"[%s] Manual compaction from level-%d to level-%d from %s .. "
"%s; will stop at %s\n",
m->cfd->GetName().c_str(), m->input_level, c->output_level(),
(m->begin ? m->begin->DebugString().c_str() : "(begin)"),
(m->end ? m->end->DebugString().c_str() : "(end)"),
((m->done || m->manual_end == nullptr)
? "(end)"
: m->manual_end->DebugString().c_str()));
}
} else if (!compaction_queue_.empty()) {
// cfd is referenced here
auto cfd = PopFirstFromCompactionQueue();
// We unreference here because the following code will take a Ref() on
// this cfd if it is going to use it (Compaction class holds a
// reference).
// This will all happen under a mutex so we don't have to be afraid of
// somebody else deleting it.
if (cfd->Unref()) {
delete cfd;
// This was the last reference of the column family, so no need to
// compact.
return Status::OK();
}
if (HaveManualCompaction(cfd)) {
// Can't compact right now, but try again later
TEST_SYNC_POINT("DBImpl::BackgroundCompaction()::Conflict");
return Status::OK();
}
// Pick up latest mutable CF Options and use it throughout the
// compaction job
// Compaction makes a copy of the latest MutableCFOptions. It should be used
// throughout the compaction procedure to make sure consistency. It will
// eventually be installed into SuperVersion
auto* mutable_cf_options = cfd->GetLatestMutableCFOptions();
if (!mutable_cf_options->disable_auto_compactions && !cfd->IsDropped()) {
// NOTE: try to avoid unnecessary copy of MutableCFOptions if
// compaction is not necessary. Need to make sure mutex is held
// until we make a copy in the following code
c.reset(cfd->PickCompaction(*mutable_cf_options, log_buffer));
if (c != nullptr) {
// update statistics
MeasureTime(stats_, NUM_FILES_IN_SINGLE_COMPACTION,
c->inputs(0)->size());
// There are three things that can change compaction score:
// 1) When flush or compaction finish. This case is covered by
// InstallSuperVersionAndScheduleWork
// 2) When MutableCFOptions changes. This case is also covered by
// InstallSuperVersionAndScheduleWork, because this is when the new
// options take effect.
// 3) When we Pick a new compaction, we "remove" those files being
// compacted from the calculation, which then influences compaction
// score. Here we check if we need the new compaction even without the
// files that are currently being compacted. If we need another
// compaction, we might be able to execute it in parallel, so we add it
// to the queue and schedule a new thread.
if (cfd->NeedsCompaction()) {
// Yes, we need more compactions!
AddToCompactionQueue(cfd);
++unscheduled_compactions_;
MaybeScheduleFlushOrCompaction();
}
}
}
}
if (!c) {
// Nothing to do
LogToBuffer(log_buffer, "Compaction nothing to do");
} else if (c->deletion_compaction()) {
// TODO(icanadi) Do we want to honor snapshots here? i.e. not delete old
// file if there is alive snapshot pointing to it
assert(c->num_input_files(1) == 0);
assert(c->level() == 0);
assert(c->column_family_data()->ioptions()->compaction_style ==
kCompactionStyleFIFO);
compaction_job_stats.num_input_files = c->num_input_files(0);
for (const auto& f : *c->inputs(0)) {
c->edit()->DeleteFile(c->level(), f->fd.GetNumber());
}
status = versions_->LogAndApply(c->column_family_data(),
*c->mutable_cf_options(), c->edit(),
&mutex_, directories_.GetDbDir());
InstallSuperVersionAndScheduleWorkWrapper(
c->column_family_data(), job_context, *c->mutable_cf_options());
LogToBuffer(log_buffer, "[%s] Deleted %d files\n",
c->column_family_data()->GetName().c_str(),
c->num_input_files(0));
*made_progress = true;
} else if (!trivial_move_disallowed && c->IsTrivialMove()) {
TEST_SYNC_POINT("DBImpl::BackgroundCompaction:TrivialMove");
// Instrument for event update
// TODO(yhchiang): add op details for showing trivial-move.
ThreadStatusUtil::SetColumnFamily(c->column_family_data());
ThreadStatusUtil::SetThreadOperation(ThreadStatus::OP_COMPACTION);
compaction_job_stats.num_input_files = c->num_input_files(0);
// Move files to next level
int32_t moved_files = 0;
int64_t moved_bytes = 0;
for (unsigned int l = 0; l < c->num_input_levels(); l++) {
if (c->level(l) == c->output_level()) {
continue;
}
for (size_t i = 0; i < c->num_input_files(l); i++) {
FileMetaData* f = c->input(l, i);
c->edit()->DeleteFile(c->level(l), f->fd.GetNumber());
c->edit()->AddFile(c->output_level(), f->fd.GetNumber(),
f->fd.GetPathId(), f->fd.GetFileSize(), f->smallest,
f->largest, f->smallest_seqno, f->largest_seqno,
f->marked_for_compaction);
LogToBuffer(log_buffer,
"[%s] Moving #%" PRIu64 " to level-%d %" PRIu64 " bytes\n",
c->column_family_data()->GetName().c_str(),
f->fd.GetNumber(), c->output_level(), f->fd.GetFileSize());
++moved_files;
moved_bytes += f->fd.GetFileSize();
}
}
status = versions_->LogAndApply(c->column_family_data(),
*c->mutable_cf_options(), c->edit(),
&mutex_, directories_.GetDbDir());
// Use latest MutableCFOptions
InstallSuperVersionAndScheduleWorkWrapper(
c->column_family_data(), job_context, *c->mutable_cf_options());
VersionStorageInfo::LevelSummaryStorage tmp;
c->column_family_data()->internal_stats()->IncBytesMoved(c->output_level(),
moved_bytes);
{
event_logger_.LogToBuffer(log_buffer)
<< "job" << job_context->job_id << "event"
<< "trivial_move"
<< "destination_level" << c->output_level() << "files" << moved_files
<< "total_files_size" << moved_bytes;
}
LogToBuffer(
log_buffer,
"[%s] Moved #%d files to level-%d %" PRIu64 " bytes %s: %s\n",
c->column_family_data()->GetName().c_str(), moved_files,
c->output_level(), moved_bytes, status.ToString().c_str(),
c->column_family_data()->current()->storage_info()->LevelSummary(&tmp));
*made_progress = true;
// Clear Instrument
ThreadStatusUtil::ResetThreadStatus();
} else {
int output_level __attribute__((unused)) = c->output_level();
TEST_SYNC_POINT_CALLBACK("DBImpl::BackgroundCompaction:NonTrivial",
&output_level);
SequenceNumber earliest_write_conflict_snapshot;
std::vector<SequenceNumber> snapshot_seqs =
snapshots_.GetAll(&earliest_write_conflict_snapshot);
assert(is_snapshot_supported_ || snapshots_.empty());
CompactionJob compaction_job(
job_context->job_id, c.get(), db_options_, env_options_,
versions_.get(), &shutting_down_, log_buffer, directories_.GetDbDir(),
directories_.GetDataDir(c->output_path_id()), stats_, snapshot_seqs,
earliest_write_conflict_snapshot, table_cache_, &event_logger_,
c->mutable_cf_options()->paranoid_file_checks,
c->mutable_cf_options()->compaction_measure_io_stats, dbname_,
&compaction_job_stats);
compaction_job.Prepare();
mutex_.Unlock();
compaction_job.Run();
TEST_SYNC_POINT("DBImpl::BackgroundCompaction:NonTrivial:AfterRun");
mutex_.Lock();
status = compaction_job.Install(*c->mutable_cf_options(), &mutex_);
if (status.ok()) {
InstallSuperVersionAndScheduleWorkWrapper(
c->column_family_data(), job_context, *c->mutable_cf_options());
}
*made_progress = true;
}
if (c != nullptr) {
NotifyOnCompactionCompleted(
c->column_family_data(), c.get(), status,
compaction_job_stats, job_context->job_id);
c->ReleaseCompactionFiles(status);
*made_progress = true;
}
// this will unref its input_version and column_family_data
c.reset();
if (status.ok()) {
// Done
} else if (status.IsShutdownInProgress()) {
// Ignore compaction errors found during shutting down
} else {
Log(InfoLogLevel::WARN_LEVEL, db_options_.info_log, "Compaction error: %s",
status.ToString().c_str());
if (db_options_.paranoid_checks && bg_error_.ok()) {
bg_error_ = status;
}
}
if (is_manual) {
ManualCompaction* m = manual_compaction;
if (!status.ok()) {
m->status = status;
m->done = true;
}
// For universal compaction:
// Because universal compaction always happens at level 0, so one
// compaction will pick up all overlapped files. No files will be
// filtered out due to size limit and left for a successive compaction.
// So we can safely conclude the current compaction.
//
// Also note that, if we don't stop here, then the current compaction
// writes a new file back to level 0, which will be used in successive
// compaction. Hence the manual compaction will never finish.
//
// Stop the compaction if manual_end points to nullptr -- this means
// that we compacted the whole range. manual_end should always point
// to nullptr in case of universal compaction
if (m->manual_end == nullptr) {
m->done = true;
}
if (!m->done) {
// We only compacted part of the requested range. Update *m
// to the range that is left to be compacted.
// Universal and FIFO compactions should always compact the whole range
assert(m->cfd->ioptions()->compaction_style !=
kCompactionStyleUniversal ||
m->cfd->ioptions()->num_levels > 1);
assert(m->cfd->ioptions()->compaction_style != kCompactionStyleFIFO);
m->tmp_storage = *m->manual_end;
m->begin = &m->tmp_storage;
m->incomplete = true;
}
m->in_progress = false; // not being processed anymore
}
return status;
}
bool DBImpl::HasPendingManualCompaction() {
return (!manual_compaction_dequeue_.empty());
}
void DBImpl::AddManualCompaction(DBImpl::ManualCompaction* m) {
manual_compaction_dequeue_.push_back(m);
}
void DBImpl::RemoveManualCompaction(DBImpl::ManualCompaction* m) {
// Remove from queue
std::deque<ManualCompaction*>::iterator it =
manual_compaction_dequeue_.begin();
while (it != manual_compaction_dequeue_.end()) {
if (m == (*it)) {
it = manual_compaction_dequeue_.erase(it);
return;
}
it++;
}
assert(false);
return;
}
bool DBImpl::ShouldntRunManualCompaction(ManualCompaction* m) {
if (m->exclusive) {
return (bg_compaction_scheduled_ > 0);
}
std::deque<ManualCompaction*>::iterator it =
manual_compaction_dequeue_.begin();
bool seen = false;
while (it != manual_compaction_dequeue_.end()) {
if (m == (*it)) {
it++;
seen = true;
continue;
} else if (MCOverlap(m, (*it)) && (!seen && !(*it)->in_progress)) {
// Consider the other manual compaction *it, conflicts if:
// overlaps with m
// and (*it) is ahead in the queue and is not yet in progress
return true;
}
it++;
}
return false;
}
bool DBImpl::HaveManualCompaction(ColumnFamilyData* cfd) {
// Remove from priority queue
std::deque<ManualCompaction*>::iterator it =
manual_compaction_dequeue_.begin();
while (it != manual_compaction_dequeue_.end()) {
if ((*it)->exclusive) {
return true;
}
if ((cfd == (*it)->cfd) && (!((*it)->in_progress || (*it)->done))) {
// Allow automatic compaction if manual compaction is
// is in progress
return true;
}
it++;
}
return false;
}
bool DBImpl::HasExclusiveManualCompaction() {
// Remove from priority queue
std::deque<ManualCompaction*>::iterator it =
manual_compaction_dequeue_.begin();
while (it != manual_compaction_dequeue_.end()) {
if ((*it)->exclusive) {
return true;
}
it++;
}
return false;
}
bool DBImpl::MCOverlap(ManualCompaction* m, ManualCompaction* m1) {
if ((m->exclusive) || (m1->exclusive)) {
return true;
}
if (m->cfd != m1->cfd) {
return false;
}
return true;
}
namespace {
struct IterState {
IterState(DBImpl* _db, InstrumentedMutex* _mu, SuperVersion* _super_version)
: db(_db), mu(_mu), super_version(_super_version) {}
DBImpl* db;
InstrumentedMutex* mu;
SuperVersion* super_version;
};
static void CleanupIteratorState(void* arg1, void* arg2) {
IterState* state = reinterpret_cast<IterState*>(arg1);
if (state->super_version->Unref()) {
// Job id == 0 means that this is not our background process, but rather
// user thread
JobContext job_context(0);
state->mu->Lock();
state->super_version->Cleanup();
state->db->FindObsoleteFiles(&job_context, false, true);
state->mu->Unlock();
delete state->super_version;
if (job_context.HaveSomethingToDelete()) {
state->db->PurgeObsoleteFiles(job_context);
}
job_context.Clean();
}
delete state;
}
} // namespace
InternalIterator* DBImpl::NewInternalIterator(const ReadOptions& read_options,
ColumnFamilyData* cfd,
SuperVersion* super_version,
Arena* arena) {
InternalIterator* internal_iter;
assert(arena != nullptr);
// Need to create internal iterator from the arena.
MergeIteratorBuilder merge_iter_builder(&cfd->internal_comparator(), arena);
// Collect iterator for mutable mem
merge_iter_builder.AddIterator(
super_version->mem->NewIterator(read_options, arena));
// Collect all needed child iterators for immutable memtables
super_version->imm->AddIterators(read_options, &merge_iter_builder);
// Collect iterators for files in L0 - Ln
super_version->current->AddIterators(read_options, env_options_,
&merge_iter_builder);
internal_iter = merge_iter_builder.Finish();
IterState* cleanup = new IterState(this, &mutex_, super_version);
internal_iter->RegisterCleanup(CleanupIteratorState, cleanup, nullptr);
return internal_iter;
}
ColumnFamilyHandle* DBImpl::DefaultColumnFamily() const {
return default_cf_handle_;
}
Status DBImpl::Get(const ReadOptions& read_options,
ColumnFamilyHandle* column_family, const Slice& key,
std::string* value) {
return GetImpl(read_options, column_family, key, value);
}
// JobContext gets created and destructed outside of the lock --
// we
// use this convinently to:
// * malloc one SuperVersion() outside of the lock -- new_superversion
// * delete SuperVersion()s outside of the lock -- superversions_to_free
//
// However, if InstallSuperVersionAndScheduleWork() gets called twice with the
// same job_context, we can't reuse the SuperVersion() that got
// malloced because
// first call already used it. In that rare case, we take a hit and create a
// new SuperVersion() inside of the mutex. We do similar thing
// for superversion_to_free
void DBImpl::InstallSuperVersionAndScheduleWorkWrapper(
ColumnFamilyData* cfd, JobContext* job_context,
const MutableCFOptions& mutable_cf_options) {
mutex_.AssertHeld();
SuperVersion* old_superversion = InstallSuperVersionAndScheduleWork(
cfd, job_context->new_superversion, mutable_cf_options);
job_context->new_superversion = nullptr;
job_context->superversions_to_free.push_back(old_superversion);
}
SuperVersion* DBImpl::InstallSuperVersionAndScheduleWork(
ColumnFamilyData* cfd, SuperVersion* new_sv,
const MutableCFOptions& mutable_cf_options) {
mutex_.AssertHeld();
// Update max_total_in_memory_state_
size_t old_memtable_size = 0;
auto* old_sv = cfd->GetSuperVersion();
if (old_sv) {
old_memtable_size = old_sv->mutable_cf_options.write_buffer_size *
old_sv->mutable_cf_options.max_write_buffer_number;
}
auto* old = cfd->InstallSuperVersion(
new_sv ? new_sv : new SuperVersion(), &mutex_, mutable_cf_options);
// Whenever we install new SuperVersion, we might need to issue new flushes or
// compactions.
SchedulePendingFlush(cfd);
SchedulePendingCompaction(cfd);
MaybeScheduleFlushOrCompaction();
// Update max_total_in_memory_state_
max_total_in_memory_state_ =
max_total_in_memory_state_ - old_memtable_size +
mutable_cf_options.write_buffer_size *
mutable_cf_options.max_write_buffer_number;
return old;
}
Status DBImpl::GetImpl(const ReadOptions& read_options,
ColumnFamilyHandle* column_family, const Slice& key,
std::string* value, bool* value_found) {
StopWatch sw(env_, stats_, DB_GET);
PERF_TIMER_GUARD(get_snapshot_time);
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
SequenceNumber snapshot;
if (read_options.snapshot != nullptr) {
snapshot = reinterpret_cast<const SnapshotImpl*>(
read_options.snapshot)->number_;
} else {
snapshot = versions_->LastSequence();
}
// Acquire SuperVersion
SuperVersion* sv = GetAndRefSuperVersion(cfd);
// Prepare to store a list of merge operations if merge occurs.
MergeContext merge_context;
Status s;
// First look in the memtable, then in the immutable memtable (if any).
// s is both in/out. When in, s could either be OK or MergeInProgress.
// merge_operands will contain the sequence of merges in the latter case.
LookupKey lkey(key, snapshot);
PERF_TIMER_STOP(get_snapshot_time);
if (sv->mem->Get(lkey, value, &s, &merge_context)) {
// Done
RecordTick(stats_, MEMTABLE_HIT);
} else if (sv->imm->Get(lkey, value, &s, &merge_context)) {
// Done
RecordTick(stats_, MEMTABLE_HIT);
} else {
PERF_TIMER_GUARD(get_from_output_files_time);
sv->current->Get(read_options, lkey, value, &s, &merge_context,
value_found);
RecordTick(stats_, MEMTABLE_MISS);
}
{
PERF_TIMER_GUARD(get_post_process_time);
ReturnAndCleanupSuperVersion(cfd, sv);
RecordTick(stats_, NUMBER_KEYS_READ);
RecordTick(stats_, BYTES_READ, value->size());
}
return s;
}
std::vector<Status> DBImpl::MultiGet(
const ReadOptions& read_options,
const std::vector<ColumnFamilyHandle*>& column_family,
const std::vector<Slice>& keys, std::vector<std::string>* values) {
StopWatch sw(env_, stats_, DB_MULTIGET);
PERF_TIMER_GUARD(get_snapshot_time);
SequenceNumber snapshot;
struct MultiGetColumnFamilyData {
ColumnFamilyData* cfd;
SuperVersion* super_version;
};
std::unordered_map<uint32_t, MultiGetColumnFamilyData*> multiget_cf_data;
// fill up and allocate outside of mutex
for (auto cf : column_family) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(cf);
auto cfd = cfh->cfd();
if (multiget_cf_data.find(cfd->GetID()) == multiget_cf_data.end()) {
auto mgcfd = new MultiGetColumnFamilyData();
mgcfd->cfd = cfd;
multiget_cf_data.insert({cfd->GetID(), mgcfd});
}
}
mutex_.Lock();
if (read_options.snapshot != nullptr) {
snapshot = reinterpret_cast<const SnapshotImpl*>(
read_options.snapshot)->number_;
} else {
snapshot = versions_->LastSequence();
}
for (auto mgd_iter : multiget_cf_data) {
mgd_iter.second->super_version =
mgd_iter.second->cfd->GetSuperVersion()->Ref();
}
mutex_.Unlock();
// Contain a list of merge operations if merge occurs.
MergeContext merge_context;
// Note: this always resizes the values array
size_t num_keys = keys.size();
std::vector<Status> stat_list(num_keys);
values->resize(num_keys);
// Keep track of bytes that we read for statistics-recording later
uint64_t bytes_read = 0;
PERF_TIMER_STOP(get_snapshot_time);
// For each of the given keys, apply the entire "get" process as follows:
// First look in the memtable, then in the immutable memtable (if any).
// s is both in/out. When in, s could either be OK or MergeInProgress.
// merge_operands will contain the sequence of merges in the latter case.
for (size_t i = 0; i < num_keys; ++i) {
merge_context.Clear();
Status& s = stat_list[i];
std::string* value = &(*values)[i];
LookupKey lkey(keys[i], snapshot);
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family[i]);
auto mgd_iter = multiget_cf_data.find(cfh->cfd()->GetID());
assert(mgd_iter != multiget_cf_data.end());
auto mgd = mgd_iter->second;
auto super_version = mgd->super_version;
if (super_version->mem->Get(lkey, value, &s, &merge_context)) {
// Done
} else if (super_version->imm->Get(lkey, value, &s, &merge_context)) {
// Done
} else {
PERF_TIMER_GUARD(get_from_output_files_time);
super_version->current->Get(read_options, lkey, value, &s,
&merge_context);
}
if (s.ok()) {
bytes_read += value->size();
}
}
// Post processing (decrement reference counts and record statistics)
PERF_TIMER_GUARD(get_post_process_time);
autovector<SuperVersion*> superversions_to_delete;
// TODO(icanadi) do we need lock here or just around Cleanup()?
mutex_.Lock();
for (auto mgd_iter : multiget_cf_data) {
auto mgd = mgd_iter.second;
if (mgd->super_version->Unref()) {
mgd->super_version->Cleanup();
superversions_to_delete.push_back(mgd->super_version);
}
}
mutex_.Unlock();
for (auto td : superversions_to_delete) {
delete td;
}
for (auto mgd : multiget_cf_data) {
delete mgd.second;
}
RecordTick(stats_, NUMBER_MULTIGET_CALLS);
RecordTick(stats_, NUMBER_MULTIGET_KEYS_READ, num_keys);
RecordTick(stats_, NUMBER_MULTIGET_BYTES_READ, bytes_read);
PERF_TIMER_STOP(get_post_process_time);
return stat_list;
}
#ifndef ROCKSDB_LITE
Status DBImpl::AddFile(ColumnFamilyHandle* column_family,
const std::string& file_path, bool move_file) {
Status status;
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
ColumnFamilyData* cfd = cfh->cfd();
ExternalSstFileInfo file_info;
file_info.file_path = file_path;
status = env_->GetFileSize(file_path, &file_info.file_size);
if (!status.ok()) {
return status;
}
// Access the file using TableReader to extract
// version, number of entries, smallest user key, largest user key
std::unique_ptr<RandomAccessFile> sst_file;
status = env_->NewRandomAccessFile(file_path, &sst_file, env_options_);
if (!status.ok()) {
return status;
}
std::unique_ptr<RandomAccessFileReader> sst_file_reader;
sst_file_reader.reset(new RandomAccessFileReader(std::move(sst_file)));
std::unique_ptr<TableReader> table_reader;
status = cfd->ioptions()->table_factory->NewTableReader(
TableReaderOptions(*cfd->ioptions(), env_options_,
cfd->internal_comparator()),
std::move(sst_file_reader), file_info.file_size, &table_reader);
if (!status.ok()) {
return status;
}
// Get the external sst file version from table properties
const UserCollectedProperties& user_collected_properties =
table_reader->GetTableProperties()->user_collected_properties;
UserCollectedProperties::const_iterator external_sst_file_version_iter =
user_collected_properties.find(ExternalSstFilePropertyNames::kVersion);
if (external_sst_file_version_iter == user_collected_properties.end()) {
return Status::InvalidArgument("Generated table version not found");
}
file_info.version =
DecodeFixed32(external_sst_file_version_iter->second.c_str());
if (file_info.version == 1) {
// version 1 imply that all sequence numbers in table equal 0
file_info.sequence_number = 0;
} else {
return Status::InvalidArgument("Generated table version is not supported");
}
// Get number of entries in table
file_info.num_entries = table_reader->GetTableProperties()->num_entries;
ParsedInternalKey key;
std::unique_ptr<InternalIterator> iter(
table_reader->NewIterator(ReadOptions()));
// Get first (smallest) key from file
iter->SeekToFirst();
if (!ParseInternalKey(iter->key(), &key)) {
return Status::Corruption("Generated table have corrupted keys");
}
if (key.sequence != 0) {
return Status::Corruption("Generated table have non zero sequence number");
}
file_info.smallest_key = key.user_key.ToString();
// Get last (largest) key from file
iter->SeekToLast();
if (!ParseInternalKey(iter->key(), &key)) {
return Status::Corruption("Generated table have corrupted keys");
}
if (key.sequence != 0) {
return Status::Corruption("Generated table have non zero sequence number");
}
file_info.largest_key = key.user_key.ToString();
return AddFile(column_family, &file_info, move_file);
}
Status DBImpl::AddFile(ColumnFamilyHandle* column_family,
const ExternalSstFileInfo* file_info, bool move_file) {
Status status;
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
ColumnFamilyData* cfd = cfh->cfd();
if (file_info->version != 1) {
return Status::InvalidArgument("Generated table version is not supported");
}
// version 1 imply that file have only Put Operations with Sequence Number = 0
FileMetaData meta;
meta.smallest =
InternalKey(file_info->smallest_key, file_info->sequence_number,
ValueType::kTypeValue);
meta.largest = InternalKey(file_info->largest_key, file_info->sequence_number,
ValueType::kTypeValue);
if (!meta.smallest.Valid() || !meta.largest.Valid()) {
return Status::Corruption("Generated table have corrupted keys");
}
meta.smallest_seqno = file_info->sequence_number;
meta.largest_seqno = file_info->sequence_number;
if (meta.smallest_seqno != 0 || meta.largest_seqno != 0) {
return Status::InvalidArgument(
"Non zero sequence numbers are not supported");
}
// Generate a location for the new table
meta.fd = FileDescriptor(versions_->NewFileNumber(), 0, file_info->file_size);
std::string db_fname = TableFileName(
db_options_.db_paths, meta.fd.GetNumber(), meta.fd.GetPathId());
if (move_file) {
status = env_->LinkFile(file_info->file_path, db_fname);
if (status.IsNotSupported()) {
// Original file is on a different FS, use copy instead of hard linking
status = CopyFile(env_, file_info->file_path, db_fname, 0);
}
} else {
status = CopyFile(env_, file_info->file_path, db_fname, 0);
}
if (!status.ok()) {
return status;
}
{
InstrumentedMutexLock l(&mutex_);
const MutableCFOptions mutable_cf_options =
*cfd->GetLatestMutableCFOptions();
WriteThread::Writer w;
write_thread_.EnterUnbatched(&w, &mutex_);
if (!snapshots_.empty()) {
// Check that no snapshots are being held
status =
Status::NotSupported("Cannot add a file while holding snapshots");
}
if (status.ok()) {
// Verify that added file key range dont overlap with any keys in DB
SuperVersion* sv = cfd->GetSuperVersion()->Ref();
Arena arena;
ReadOptions ro;
ro.total_order_seek = true;
ScopedArenaIterator iter(NewInternalIterator(ro, cfd, sv, &arena));
InternalKey range_start(file_info->smallest_key, kMaxSequenceNumber,
kTypeValue);
iter->Seek(range_start.Encode());
status = iter->status();
if (status.ok() && iter->Valid()) {
ParsedInternalKey seek_result;
if (ParseInternalKey(iter->key(), &seek_result)) {
auto* vstorage = cfd->current()->storage_info();
if (vstorage->InternalComparator()->user_comparator()->Compare(
seek_result.user_key, file_info->largest_key) <= 0) {
status = Status::NotSupported("Cannot add overlapping range");
}
} else {
status = Status::Corruption("DB have corrupted keys");
}
}
}
if (status.ok()) {
// Add file to L0
VersionEdit edit;
edit.SetColumnFamily(cfd->GetID());
edit.AddFile(0, meta.fd.GetNumber(), meta.fd.GetPathId(),
meta.fd.GetFileSize(), meta.smallest, meta.largest,
meta.smallest_seqno, meta.largest_seqno,
meta.marked_for_compaction);
status = versions_->LogAndApply(cfd, mutable_cf_options, &edit, &mutex_,
directories_.GetDbDir());
}
write_thread_.ExitUnbatched(&w);
if (status.ok()) {
delete InstallSuperVersionAndScheduleWork(cfd, nullptr,
mutable_cf_options);
}
}
if (!status.ok()) {
// We failed to add the file to the database
Status s = env_->DeleteFile(db_fname);
if (!s.ok()) {
Log(InfoLogLevel::WARN_LEVEL, db_options_.info_log,
"AddFile() clean up for file %s failed : %s", db_fname.c_str(),
s.ToString().c_str());
}
} else if (status.ok() && move_file) {
// The file was moved and added successfully, remove original file link
Status s = env_->DeleteFile(file_info->file_path);
if (!s.ok()) {
Log(InfoLogLevel::WARN_LEVEL, db_options_.info_log,
"%s was added to DB successfully but failed to remove original file "
"link : %s",
file_info->file_path.c_str(), s.ToString().c_str());
}
}
return status;
}
#endif // ROCKSDB_LITE
Status DBImpl::CreateColumnFamily(const ColumnFamilyOptions& cf_options,
const std::string& column_family_name,
ColumnFamilyHandle** handle) {
Status s;
Status persist_options_status;
*handle = nullptr;
s = CheckCompressionSupported(cf_options);
if (s.ok() && db_options_.allow_concurrent_memtable_write) {
s = CheckConcurrentWritesSupported(cf_options);
}
if (!s.ok()) {
return s;
}
{
InstrumentedMutexLock l(&mutex_);
if (versions_->GetColumnFamilySet()->GetColumnFamily(column_family_name) !=
nullptr) {
return Status::InvalidArgument("Column family already exists");
}
VersionEdit edit;
edit.AddColumnFamily(column_family_name);
uint32_t new_id = versions_->GetColumnFamilySet()->GetNextColumnFamilyID();
edit.SetColumnFamily(new_id);
edit.SetLogNumber(logfile_number_);
edit.SetComparatorName(cf_options.comparator->Name());
// LogAndApply will both write the creation in MANIFEST and create
// ColumnFamilyData object
Options opt(db_options_, cf_options);
{ // write thread
WriteThread::Writer w;
write_thread_.EnterUnbatched(&w, &mutex_);
// LogAndApply will both write the creation in MANIFEST and create
// ColumnFamilyData object
s = versions_->LogAndApply(
nullptr, MutableCFOptions(opt, ImmutableCFOptions(opt)), &edit,
&mutex_, directories_.GetDbDir(), false, &cf_options);
if (s.ok()) {
// If the column family was created successfully, we then persist
// the updated RocksDB options under the same single write thread
persist_options_status = WriteOptionsFile();
}
write_thread_.ExitUnbatched(&w);
}
if (s.ok()) {
single_column_family_mode_ = false;
auto* cfd =
versions_->GetColumnFamilySet()->GetColumnFamily(column_family_name);
assert(cfd != nullptr);
delete InstallSuperVersionAndScheduleWork(
cfd, nullptr, *cfd->GetLatestMutableCFOptions());
if (!cfd->mem()->IsSnapshotSupported()) {
is_snapshot_supported_ = false;
}
*handle = new ColumnFamilyHandleImpl(cfd, this, &mutex_);
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"Created column family [%s] (ID %u)",
column_family_name.c_str(), (unsigned)cfd->GetID());
} else {
Log(InfoLogLevel::ERROR_LEVEL, db_options_.info_log,
"Creating column family [%s] FAILED -- %s",
column_family_name.c_str(), s.ToString().c_str());
}
} // InstrumentedMutexLock l(&mutex_)
// this is outside the mutex
if (s.ok()) {
NewThreadStatusCfInfo(
reinterpret_cast<ColumnFamilyHandleImpl*>(*handle)->cfd());
if (!persist_options_status.ok()) {
if (db_options_.fail_if_options_file_error) {
s = Status::IOError(
"ColumnFamily has been created, but unable to persist"
"options in CreateColumnFamily()",
persist_options_status.ToString().c_str());
}
Warn(db_options_.info_log,
"Unable to persist options in CreateColumnFamily() -- %s",
persist_options_status.ToString().c_str());
}
}
return s;
}
Status DBImpl::DropColumnFamily(ColumnFamilyHandle* column_family) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
if (cfd->GetID() == 0) {
return Status::InvalidArgument("Can't drop default column family");
}
bool cf_support_snapshot = cfd->mem()->IsSnapshotSupported();
VersionEdit edit;
edit.DropColumnFamily();
edit.SetColumnFamily(cfd->GetID());
Status s;
Status options_persist_status;
{
InstrumentedMutexLock l(&mutex_);
if (cfd->IsDropped()) {
s = Status::InvalidArgument("Column family already dropped!\n");
}
if (s.ok()) {
// we drop column family from a single write thread
WriteThread::Writer w;
write_thread_.EnterUnbatched(&w, &mutex_);
s = versions_->LogAndApply(cfd, *cfd->GetLatestMutableCFOptions(),
&edit, &mutex_);
if (s.ok()) {
// If the column family was dropped successfully, we then persist
// the updated RocksDB options under the same single write thread
options_persist_status = WriteOptionsFile();
}
write_thread_.ExitUnbatched(&w);
}
if (!cf_support_snapshot) {
// Dropped Column Family doesn't support snapshot. Need to recalculate
// is_snapshot_supported_.
bool new_is_snapshot_supported = true;
for (auto c : *versions_->GetColumnFamilySet()) {
if (!c->IsDropped() && !c->mem()->IsSnapshotSupported()) {
new_is_snapshot_supported = false;
break;
}
}
is_snapshot_supported_ = new_is_snapshot_supported;
}
}
if (s.ok()) {
// Note that here we erase the associated cf_info of the to-be-dropped
// cfd before its ref-count goes to zero to avoid having to erase cf_info
// later inside db_mutex.
EraseThreadStatusCfInfo(cfd);
assert(cfd->IsDropped());
auto* mutable_cf_options = cfd->GetLatestMutableCFOptions();
max_total_in_memory_state_ -= mutable_cf_options->write_buffer_size *
mutable_cf_options->max_write_buffer_number;
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"Dropped column family with id %u\n", cfd->GetID());
if (!options_persist_status.ok()) {
if (db_options_.fail_if_options_file_error) {
s = Status::IOError(
"ColumnFamily has been dropped, but unable to persist "
"options in DropColumnFamily()",
options_persist_status.ToString().c_str());
}
Warn(db_options_.info_log,
"Unable to persist options in DropColumnFamily() -- %s",
options_persist_status.ToString().c_str());
}
} else {
Log(InfoLogLevel::ERROR_LEVEL, db_options_.info_log,
"Dropping column family with id %u FAILED -- %s\n",
cfd->GetID(), s.ToString().c_str());
}
return s;
}
bool DBImpl::KeyMayExist(const ReadOptions& read_options,
ColumnFamilyHandle* column_family, const Slice& key,
std::string* value, bool* value_found) {
if (value_found != nullptr) {
// falsify later if key-may-exist but can't fetch value
*value_found = true;
}
ReadOptions roptions = read_options;
roptions.read_tier = kBlockCacheTier; // read from block cache only
auto s = GetImpl(roptions, column_family, key, value, value_found);
// If block_cache is enabled and the index block of the table didn't
// not present in block_cache, the return value will be Status::Incomplete.
// In this case, key may still exist in the table.
return s.ok() || s.IsIncomplete();
}
Iterator* DBImpl::NewIterator(const ReadOptions& read_options,
ColumnFamilyHandle* column_family) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
XFUNC_TEST("", "managed_new", managed_new1, xf_manage_new,
reinterpret_cast<DBImpl*>(this),
const_cast<ReadOptions*>(&read_options), is_snapshot_supported_);
if (read_options.managed) {
#ifdef ROCKSDB_LITE
// not supported in lite version
return NewErrorIterator(Status::InvalidArgument(
"Managed Iterators not supported in RocksDBLite."));
#else
if ((read_options.tailing) || (read_options.snapshot != nullptr) ||
(is_snapshot_supported_)) {
return new ManagedIterator(this, read_options, cfd);
}
// Managed iter not supported
return NewErrorIterator(Status::InvalidArgument(
"Managed Iterators not supported without snapshots."));
#endif
} else if (read_options.tailing) {
#ifdef ROCKSDB_LITE
// not supported in lite version
return nullptr;
#else
SuperVersion* sv = cfd->GetReferencedSuperVersion(&mutex_);
auto iter = new ForwardIterator(this, read_options, cfd, sv);
return NewDBIterator(
env_, *cfd->ioptions(), cfd->user_comparator(), iter,
kMaxSequenceNumber,
sv->mutable_cf_options.max_sequential_skip_in_iterations,
read_options.iterate_upper_bound, read_options.prefix_same_as_start,
read_options.pin_data);
#endif
} else {
SequenceNumber latest_snapshot = versions_->LastSequence();
SuperVersion* sv = cfd->GetReferencedSuperVersion(&mutex_);
auto snapshot =
read_options.snapshot != nullptr
? reinterpret_cast<const SnapshotImpl*>(
read_options.snapshot)->number_
: latest_snapshot;
// Try to generate a DB iterator tree in continuous memory area to be
// cache friendly. Here is an example of result:
// +-------------------------------+
// | |
// | ArenaWrappedDBIter |
// | + |
// | +---> Inner Iterator ------------+
// | | | |
// | | +-- -- -- -- -- -- -- --+ |
// | +--- | Arena | |
// | | | |
// | Allocated Memory: | |
// | | +-------------------+ |
// | | | DBIter | <---+
// | | + |
// | | | +-> iter_ ------------+
// | | | | |
// | | +-------------------+ |
// | | | MergingIterator | <---+
// | | + |
// | | | +->child iter1 ------------+
// | | | | | |
// | | +->child iter2 ----------+ |
// | | | | | | |
// | | | +->child iter3 --------+ | |
// | | | | | |
// | | +-------------------+ | | |
// | | | Iterator1 | <--------+
// | | +-------------------+ | |
// | | | Iterator2 | <------+
// | | +-------------------+ |
// | | | Iterator3 | <----+
// | | +-------------------+
// | | |
// +-------+-----------------------+
//
// ArenaWrappedDBIter inlines an arena area where all the iterators in
// the iterator tree are allocated in the order of being accessed when
// querying.
// Laying out the iterators in the order of being accessed makes it more
// likely that any iterator pointer is close to the iterator it points to so
// that they are likely to be in the same cache line and/or page.
ArenaWrappedDBIter* db_iter = NewArenaWrappedDbIterator(
env_, *cfd->ioptions(), cfd->user_comparator(), snapshot,
sv->mutable_cf_options.max_sequential_skip_in_iterations,
read_options.iterate_upper_bound, read_options.prefix_same_as_start,
read_options.pin_data);
InternalIterator* internal_iter =
NewInternalIterator(read_options, cfd, sv, db_iter->GetArena());
db_iter->SetIterUnderDBIter(internal_iter);
return db_iter;
}
// To stop compiler from complaining
return nullptr;
}
Status DBImpl::NewIterators(
const ReadOptions& read_options,
const std::vector<ColumnFamilyHandle*>& column_families,
std::vector<Iterator*>* iterators) {
iterators->clear();
iterators->reserve(column_families.size());
XFUNC_TEST("", "managed_new", managed_new1, xf_manage_new,
reinterpret_cast<DBImpl*>(this),
const_cast<ReadOptions*>(&read_options), is_snapshot_supported_);
if (read_options.managed) {
#ifdef ROCKSDB_LITE
return Status::InvalidArgument(
"Managed interator not supported in RocksDB lite");
#else
if ((!read_options.tailing) && (read_options.snapshot == nullptr) &&
(!is_snapshot_supported_)) {
return Status::InvalidArgument(
"Managed interator not supported without snapshots");
}
for (auto cfh : column_families) {
auto cfd = reinterpret_cast<ColumnFamilyHandleImpl*>(cfh)->cfd();
auto iter = new ManagedIterator(this, read_options, cfd);
iterators->push_back(iter);
}
#endif
} else if (read_options.tailing) {
#ifdef ROCKSDB_LITE
return Status::InvalidArgument(
"Tailing interator not supported in RocksDB lite");
#else
for (auto cfh : column_families) {
auto cfd = reinterpret_cast<ColumnFamilyHandleImpl*>(cfh)->cfd();
SuperVersion* sv = cfd->GetReferencedSuperVersion(&mutex_);
auto iter = new ForwardIterator(this, read_options, cfd, sv);
iterators->push_back(NewDBIterator(
env_, *cfd->ioptions(), cfd->user_comparator(), iter,
kMaxSequenceNumber,
sv->mutable_cf_options.max_sequential_skip_in_iterations, nullptr,
false, read_options.pin_data));
}
#endif
} else {
SequenceNumber latest_snapshot = versions_->LastSequence();
for (size_t i = 0; i < column_families.size(); ++i) {
auto* cfd = reinterpret_cast<ColumnFamilyHandleImpl*>(
column_families[i])->cfd();
SuperVersion* sv = cfd->GetReferencedSuperVersion(&mutex_);
auto snapshot =
read_options.snapshot != nullptr
? reinterpret_cast<const SnapshotImpl*>(
read_options.snapshot)->number_
: latest_snapshot;
ArenaWrappedDBIter* db_iter = NewArenaWrappedDbIterator(
env_, *cfd->ioptions(), cfd->user_comparator(), snapshot,
sv->mutable_cf_options.max_sequential_skip_in_iterations, nullptr,
false, read_options.pin_data);
InternalIterator* internal_iter =
NewInternalIterator(read_options, cfd, sv, db_iter->GetArena());
db_iter->SetIterUnderDBIter(internal_iter);
iterators->push_back(db_iter);
}
}
return Status::OK();
}
const Snapshot* DBImpl::GetSnapshot() { return GetSnapshotImpl(false); }
#ifndef ROCKSDB_LITE
const Snapshot* DBImpl::GetSnapshotForWriteConflictBoundary() {
return GetSnapshotImpl(true);
}
#endif // ROCKSDB_LITE
const Snapshot* DBImpl::GetSnapshotImpl(bool is_write_conflict_boundary) {
int64_t unix_time = 0;
env_->GetCurrentTime(&unix_time); // Ignore error
SnapshotImpl* s = new SnapshotImpl;
InstrumentedMutexLock l(&mutex_);
// returns null if the underlying memtable does not support snapshot.
if (!is_snapshot_supported_) {
delete s;
return nullptr;
}
return snapshots_.New(s, versions_->LastSequence(), unix_time,
is_write_conflict_boundary);
}
void DBImpl::ReleaseSnapshot(const Snapshot* s) {
const SnapshotImpl* casted_s = reinterpret_cast<const SnapshotImpl*>(s);
{
InstrumentedMutexLock l(&mutex_);
snapshots_.Delete(casted_s);
}
delete casted_s;
}
// Convenience methods
Status DBImpl::Put(const WriteOptions& o, ColumnFamilyHandle* column_family,
const Slice& key, const Slice& val) {
return DB::Put(o, column_family, key, val);
}
Status DBImpl::Merge(const WriteOptions& o, ColumnFamilyHandle* column_family,
const Slice& key, const Slice& val) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
if (!cfh->cfd()->ioptions()->merge_operator) {
return Status::NotSupported("Provide a merge_operator when opening DB");
} else {
return DB::Merge(o, column_family, key, val);
}
}
Status DBImpl::Delete(const WriteOptions& write_options,
ColumnFamilyHandle* column_family, const Slice& key) {
return DB::Delete(write_options, column_family, key);
}
Status DBImpl::SingleDelete(const WriteOptions& write_options,
ColumnFamilyHandle* column_family,
const Slice& key) {
return DB::SingleDelete(write_options, column_family, key);
}
Status DBImpl::Write(const WriteOptions& write_options, WriteBatch* my_batch) {
return WriteImpl(write_options, my_batch, nullptr);
}
#ifndef ROCKSDB_LITE
Status DBImpl::WriteWithCallback(const WriteOptions& write_options,
WriteBatch* my_batch,
WriteCallback* callback) {
return WriteImpl(write_options, my_batch, callback);
}
#endif // ROCKSDB_LITE
Status DBImpl::WriteImpl(const WriteOptions& write_options,
WriteBatch* my_batch, WriteCallback* callback) {
if (my_batch == nullptr) {
return Status::Corruption("Batch is nullptr!");
}
if (write_options.timeout_hint_us != 0) {
return Status::InvalidArgument("timeout_hint_us is deprecated");
}
Status status;
bool callback_failed = false;
bool xfunc_attempted_write = false;
XFUNC_TEST("transaction", "transaction_xftest_write_impl",
xf_transaction_write1, xf_transaction_write, write_options,
db_options_, my_batch, callback, this, &status,
&xfunc_attempted_write);
if (xfunc_attempted_write) {
// Test already did the write
return status;
}
PERF_TIMER_GUARD(write_pre_and_post_process_time);
WriteThread::Writer w;
w.batch = my_batch;
w.sync = write_options.sync;
w.disableWAL = write_options.disableWAL;
w.in_batch_group = false;
w.has_callback = (callback != nullptr) ? true : false;
if (!write_options.disableWAL) {
RecordTick(stats_, WRITE_WITH_WAL);
}
StopWatch write_sw(env_, db_options_.statistics.get(), DB_WRITE);
write_thread_.JoinBatchGroup(&w);
if (w.state == WriteThread::STATE_PARALLEL_FOLLOWER) {
// we are a non-leader in a parallel group
PERF_TIMER_GUARD(write_memtable_time);
ColumnFamilyMemTablesImpl column_family_memtables(
versions_->GetColumnFamilySet());
WriteBatchInternal::SetSequence(w.batch, w.sequence);
w.status = WriteBatchInternal::InsertInto(
w.batch, &column_family_memtables, &flush_scheduler_,
write_options.ignore_missing_column_families, 0 /*log_number*/, this,
true /*dont_filter_deletes*/, true /*concurrent_memtable_writes*/);
if (write_thread_.CompleteParallelWorker(&w)) {
// we're responsible for early exit
auto last_sequence = w.parallel_group->last_writer->sequence;
SetTickerCount(stats_, SEQUENCE_NUMBER, last_sequence);
versions_->SetLastSequence(last_sequence);
write_thread_.EarlyExitParallelGroup(&w);
}
assert(w.state == WriteThread::STATE_COMPLETED);
// STATE_COMPLETED conditional below handles exit
}
if (w.state == WriteThread::STATE_COMPLETED) {
// write is complete and leader has updated sequence
RecordTick(stats_, WRITE_DONE_BY_OTHER);
return w.status;
}
// else we are the leader of the write batch group
assert(w.state == WriteThread::STATE_GROUP_LEADER);
WriteContext context;
mutex_.Lock();
if (!write_options.disableWAL) {
default_cf_internal_stats_->AddDBStats(InternalStats::WRITE_WITH_WAL, 1);
}
RecordTick(stats_, WRITE_DONE_BY_SELF);
default_cf_internal_stats_->AddDBStats(InternalStats::WRITE_DONE_BY_SELF, 1);
// Once reaches this point, the current writer "w" will try to do its write
// job. It may also pick up some of the remaining writers in the "writers_"
// when it finds suitable, and finish them in the same write batch.
// This is how a write job could be done by the other writer.
assert(!single_column_family_mode_ ||
versions_->GetColumnFamilySet()->NumberOfColumnFamilies() == 1);
uint64_t max_total_wal_size = (db_options_.max_total_wal_size == 0)
? 4 * max_total_in_memory_state_
: db_options_.max_total_wal_size;
if (UNLIKELY(!single_column_family_mode_ &&
alive_log_files_.begin()->getting_flushed == false &&
total_log_size_ > max_total_wal_size)) {
uint64_t flush_column_family_if_log_file = alive_log_files_.begin()->number;
alive_log_files_.begin()->getting_flushed = true;
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"Flushing all column families with data in WAL number %" PRIu64
". Total log size is %" PRIu64 " while max_total_wal_size is %" PRIu64,
flush_column_family_if_log_file, total_log_size_, max_total_wal_size);
// no need to refcount because drop is happening in write thread, so can't
// happen while we're in the write thread
for (auto cfd : *versions_->GetColumnFamilySet()) {
if (cfd->IsDropped()) {
continue;
}
if (cfd->GetLogNumber() <= flush_column_family_if_log_file) {
status = SwitchMemtable(cfd, &context);
if (!status.ok()) {
break;
}
cfd->imm()->FlushRequested();
SchedulePendingFlush(cfd);
}
}
MaybeScheduleFlushOrCompaction();
} else if (UNLIKELY(write_buffer_.ShouldFlush())) {
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"Flushing column family with largest mem table size. Write buffer is "
"using %" PRIu64 " bytes out of a total of %" PRIu64 ".",
write_buffer_.memory_usage(), write_buffer_.buffer_size());
// no need to refcount because drop is happening in write thread, so can't
// happen while we're in the write thread
ColumnFamilyData* largest_cfd = nullptr;
size_t largest_cfd_size = 0;
for (auto cfd : *versions_->GetColumnFamilySet()) {
if (cfd->IsDropped()) {
continue;
}
if (!cfd->mem()->IsEmpty()) {
// We only consider active mem table, hoping immutable memtable is
// already in the process of flushing.
size_t cfd_size = cfd->mem()->ApproximateMemoryUsage();
if (largest_cfd == nullptr || cfd_size > largest_cfd_size) {
largest_cfd = cfd;
largest_cfd_size = cfd_size;
}
}
}
if (largest_cfd != nullptr) {
status = SwitchMemtable(largest_cfd, &context);
if (status.ok()) {
largest_cfd->imm()->FlushRequested();
SchedulePendingFlush(largest_cfd);
MaybeScheduleFlushOrCompaction();
}
}
}
if (UNLIKELY(status.ok() && !bg_error_.ok())) {
status = bg_error_;
}
if (UNLIKELY(status.ok() && !flush_scheduler_.Empty())) {
status = ScheduleFlushes(&context);
}
if (UNLIKELY(status.ok() && (write_controller_.IsStopped() ||
write_controller_.NeedsDelay()))) {
PERF_TIMER_STOP(write_pre_and_post_process_time);
PERF_TIMER_GUARD(write_delay_time);
// We don't know size of curent batch so that we always use the size
// for previous one. It might create a fairness issue that expiration
// might happen for smaller writes but larger writes can go through.
// Can optimize it if it is an issue.
status = DelayWrite(last_batch_group_size_);
PERF_TIMER_START(write_pre_and_post_process_time);
}
uint64_t last_sequence = versions_->LastSequence();
WriteThread::Writer* last_writer = &w;
autovector<WriteBatch*> write_batch_group;
bool need_log_sync = !write_options.disableWAL && write_options.sync;
bool need_log_dir_sync = need_log_sync && !log_dir_synced_;
if (status.ok()) {
if (need_log_sync) {
while (logs_.front().getting_synced) {
log_sync_cv_.Wait();
}
for (auto& log : logs_) {
assert(!log.getting_synced);
log.getting_synced = true;
}
}
// Add to log and apply to memtable. We can release the lock
// during this phase since &w is currently responsible for logging
// and protects against concurrent loggers and concurrent writes
// into memtables
mutex_.Unlock();
if (callback != nullptr) {
// If this write has a validation callback, check to see if this write
// is able to be written. Must be called on the write thread.
status = callback->Callback(this);
callback_failed = true;
}
} else {
mutex_.Unlock();
}
// At this point the mutex is unlocked
bool exit_completed_early = false;
last_batch_group_size_ = write_thread_.EnterAsBatchGroupLeader(
&w, &last_writer, &write_batch_group);
if (status.ok()) {
// Rules for when we can update the memtable concurrently
// 1. supported by memtable
// 2. Puts are not okay if inplace_update_support
// 3. Deletes or SingleDeletes are not okay if filtering deletes
// (controlled by both batch and memtable setting)
// 4. Merges are not okay
//
// Rules 1..3 are enforced by checking the options
// during startup (CheckConcurrentWritesSupported), so if
// options.allow_concurrent_memtable_write is true then they can be
// assumed to be true. Rule 4 is checked for each batch. We could
// relax rules 2 and 3 if we could prevent write batches from referring
// more than once to a particular key.
bool parallel = db_options_.allow_concurrent_memtable_write &&
write_batch_group.size() > 1;
int total_count = 0;
uint64_t total_byte_size = 0;
for (auto b : write_batch_group) {
total_count += WriteBatchInternal::Count(b);
total_byte_size = WriteBatchInternal::AppendedByteSize(
total_byte_size, WriteBatchInternal::ByteSize(b));
parallel = parallel && !b->HasMerge();
}
const SequenceNumber current_sequence = last_sequence + 1;
last_sequence += total_count;
// Record statistics
RecordTick(stats_, NUMBER_KEYS_WRITTEN, total_count);
RecordTick(stats_, BYTES_WRITTEN, total_byte_size);
PERF_TIMER_STOP(write_pre_and_post_process_time);
if (write_options.disableWAL) {
flush_on_destroy_ = true;
}
uint64_t log_size = 0;
if (!write_options.disableWAL) {
PERF_TIMER_GUARD(write_wal_time);
WriteBatch* merged_batch = nullptr;
if (write_batch_group.size() == 1) {
merged_batch = write_batch_group[0];
} else {
// WAL needs all of the batches flattened into a single batch.
// We could avoid copying here with an iov-like AddRecord
// interface
merged_batch = &tmp_batch_;
for (auto b : write_batch_group) {
WriteBatchInternal::Append(merged_batch, b);
}
}
WriteBatchInternal::SetSequence(merged_batch, current_sequence);
assert(WriteBatchInternal::Count(merged_batch) == total_count);
assert(WriteBatchInternal::ByteSize(merged_batch) == total_byte_size);
Slice log_entry = WriteBatchInternal::Contents(merged_batch);
status = logs_.back().writer->AddRecord(log_entry);
total_log_size_ += log_entry.size();
alive_log_files_.back().AddSize(log_entry.size());
log_empty_ = false;
log_size = log_entry.size();
RecordTick(stats_, WAL_FILE_BYTES, log_size);
if (status.ok() && need_log_sync) {
RecordTick(stats_, WAL_FILE_SYNCED);
StopWatch sw(env_, stats_, WAL_FILE_SYNC_MICROS);
// It's safe to access logs_ with unlocked mutex_ here because:
// - we've set getting_synced=true for all logs,
// so other threads won't pop from logs_ while we're here,
// - only writer thread can push to logs_, and we're in
// writer thread, so no one will push to logs_,
// - as long as other threads don't modify it, it's safe to read
// from std::deque from multiple threads concurrently.
for (auto& log : logs_) {
status = log.writer->file()->Sync(db_options_.use_fsync);
if (!status.ok()) {
break;
}
}
if (status.ok() && need_log_dir_sync) {
// We only sync WAL directory the first time WAL syncing is
// requested, so that in case users never turn on WAL sync,
// we can avoid the disk I/O in the write code path.
status = directories_.GetWalDir()->Fsync();
}
}
if (merged_batch == &tmp_batch_) {
tmp_batch_.Clear();
}
}
if (status.ok()) {
PERF_TIMER_GUARD(write_memtable_time);
{
// Update stats while we are an exclusive group leader, so we know
// that nobody else can be writing to these particular stats.
// We're optimistic, updating the stats before we successfully
// commit. That lets us release our leader status early in
// some cases.
auto stats = default_cf_internal_stats_;
stats->AddDBStats(InternalStats::BYTES_WRITTEN, total_byte_size);
stats->AddDBStats(InternalStats::NUMBER_KEYS_WRITTEN, total_count);
if (!write_options.disableWAL) {
if (write_options.sync) {
stats->AddDBStats(InternalStats::WAL_FILE_SYNCED, 1);
}
stats->AddDBStats(InternalStats::WAL_FILE_BYTES, log_size);
}
uint64_t for_other = write_batch_group.size() - 1;
if (for_other > 0) {
stats->AddDBStats(InternalStats::WRITE_DONE_BY_OTHER, for_other);
if (!write_options.disableWAL) {
stats->AddDBStats(InternalStats::WRITE_WITH_WAL, for_other);
}
}
}
if (!parallel) {
status = WriteBatchInternal::InsertInto(
write_batch_group, current_sequence, column_family_memtables_.get(),
&flush_scheduler_, write_options.ignore_missing_column_families,
0 /*log_number*/, this, false /*dont_filter_deletes*/);
} else {
WriteThread::ParallelGroup pg;
pg.leader = &w;
pg.last_writer = last_writer;
pg.early_exit_allowed = !need_log_sync;
pg.running.store(static_cast<uint32_t>(write_batch_group.size()),
std::memory_order_relaxed);
write_thread_.LaunchParallelFollowers(&pg, current_sequence);
ColumnFamilyMemTablesImpl column_family_memtables(
versions_->GetColumnFamilySet());
assert(w.sequence == current_sequence);
WriteBatchInternal::SetSequence(w.batch, w.sequence);
w.status = WriteBatchInternal::InsertInto(
w.batch, &column_family_memtables, &flush_scheduler_,
write_options.ignore_missing_column_families, 0 /*log_number*/,
this, true /*dont_filter_deletes*/,
true /*concurrent_memtable_writes*/);
assert(last_writer->sequence == last_sequence);
// CompleteParallelWorker returns true if this thread should
// handle exit, false means somebody else did
exit_completed_early = !write_thread_.CompleteParallelWorker(&w);
status = w.status;
assert(status.ok() || !exit_completed_early);
}
if (status.ok() && !exit_completed_early) {
SetTickerCount(stats_, SEQUENCE_NUMBER, last_sequence);
versions_->SetLastSequence(last_sequence);
if (!need_log_sync) {
write_thread_.ExitAsBatchGroupLeader(&w, last_writer, status);
exit_completed_early = true;
}
}
// A non-OK status here indicates that the state implied by the
// WAL has diverged from the in-memory state. This could be
// because of a corrupt write_batch (very bad), or because the
// client specified an invalid column family and didn't specify
// ignore_missing_column_families.
//
// Is setting bg_error_ enough here? This will at least stop
// compaction and fail any further writes.
if (!status.ok() && bg_error_.ok()) {
bg_error_ = status;
}
}
}
PERF_TIMER_START(write_pre_and_post_process_time);
if (db_options_.paranoid_checks && !status.ok() && !callback_failed &&
!status.IsBusy()) {
mutex_.Lock();
if (bg_error_.ok()) {
bg_error_ = status; // stop compaction & fail any further writes
}
mutex_.Unlock();
}
if (need_log_sync) {
mutex_.Lock();
MarkLogsSynced(logfile_number_, need_log_dir_sync, status);
mutex_.Unlock();
}
if (!exit_completed_early) {
write_thread_.ExitAsBatchGroupLeader(&w, last_writer, status);
}
return status;
}
// REQUIRES: mutex_ is held
// REQUIRES: this thread is currently at the front of the writer queue
Status DBImpl::DelayWrite(uint64_t num_bytes) {
uint64_t time_delayed = 0;
bool delayed = false;
{
StopWatch sw(env_, stats_, WRITE_STALL, &time_delayed);
auto delay = write_controller_.GetDelay(env_, num_bytes);
if (delay > 0) {
mutex_.Unlock();
delayed = true;
TEST_SYNC_POINT("DBImpl::DelayWrite:Sleep");
// hopefully we don't have to sleep more than 2 billion microseconds
env_->SleepForMicroseconds(static_cast<int>(delay));
mutex_.Lock();
}
while (bg_error_.ok() && write_controller_.IsStopped()) {
delayed = true;
TEST_SYNC_POINT("DBImpl::DelayWrite:Wait");
bg_cv_.Wait();
}
}
if (delayed) {
default_cf_internal_stats_->AddDBStats(InternalStats::WRITE_STALL_MICROS,
time_delayed);
RecordTick(stats_, STALL_MICROS, time_delayed);
}
return bg_error_;
}
Status DBImpl::ScheduleFlushes(WriteContext* context) {
ColumnFamilyData* cfd;
while ((cfd = flush_scheduler_.TakeNextColumnFamily()) != nullptr) {
auto status = SwitchMemtable(cfd, context);
if (cfd->Unref()) {
delete cfd;
}
if (!status.ok()) {
return status;
}
}
return Status::OK();
}
// REQUIRES: mutex_ is held
// REQUIRES: this thread is currently at the front of the writer queue
Status DBImpl::SwitchMemtable(ColumnFamilyData* cfd, WriteContext* context) {
mutex_.AssertHeld();
unique_ptr<WritableFile> lfile;
log::Writer* new_log = nullptr;
MemTable* new_mem = nullptr;
// Attempt to switch to a new memtable and trigger flush of old.
// Do this without holding the dbmutex lock.
assert(versions_->prev_log_number() == 0);
bool creating_new_log = !log_empty_;
uint64_t recycle_log_number = 0;
if (creating_new_log && db_options_.recycle_log_file_num &&
!log_recycle_files.empty()) {
recycle_log_number = log_recycle_files.front();
log_recycle_files.pop_front();
}
uint64_t new_log_number =
creating_new_log ? versions_->NewFileNumber() : logfile_number_;
SuperVersion* new_superversion = nullptr;
const MutableCFOptions mutable_cf_options = *cfd->GetLatestMutableCFOptions();
mutex_.Unlock();
Status s;
{
if (creating_new_log) {
EnvOptions opt_env_opt =
env_->OptimizeForLogWrite(env_options_, db_options_);
if (recycle_log_number) {
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"reusing log %" PRIu64 " from recycle list\n", recycle_log_number);
s = env_->ReuseWritableFile(
LogFileName(db_options_.wal_dir, new_log_number),
LogFileName(db_options_.wal_dir, recycle_log_number), &lfile,
opt_env_opt);
} else {
s = NewWritableFile(env_,
LogFileName(db_options_.wal_dir, new_log_number),
&lfile, opt_env_opt);
}
if (s.ok()) {
// Our final size should be less than write_buffer_size
// (compression, etc) but err on the side of caution.
lfile->SetPreallocationBlockSize(
mutable_cf_options.write_buffer_size / 10 +
mutable_cf_options.write_buffer_size);
unique_ptr<WritableFileWriter> file_writer(
new WritableFileWriter(std::move(lfile), opt_env_opt));
new_log = new log::Writer(std::move(file_writer), new_log_number,
db_options_.recycle_log_file_num > 0);
}
}
if (s.ok()) {
SequenceNumber seq = versions_->LastSequence();
new_mem = cfd->ConstructNewMemtable(mutable_cf_options, seq);
new_superversion = new SuperVersion();
}
}
Log(InfoLogLevel::DEBUG_LEVEL, db_options_.info_log,
"[%s] New memtable created with log file: #%" PRIu64 "\n",
cfd->GetName().c_str(), new_log_number);
mutex_.Lock();
if (!s.ok()) {
// how do we fail if we're not creating new log?
assert(creating_new_log);
assert(!new_mem);
assert(!new_log);
return s;
}
if (creating_new_log) {
logfile_number_ = new_log_number;
assert(new_log != nullptr);
log_empty_ = true;
log_dir_synced_ = false;
logs_.emplace_back(logfile_number_, new_log);
alive_log_files_.push_back(LogFileNumberSize(logfile_number_));
for (auto loop_cfd : *versions_->GetColumnFamilySet()) {
// all this is just optimization to delete logs that
// are no longer needed -- if CF is empty, that means it
// doesn't need that particular log to stay alive, so we just
// advance the log number. no need to persist this in the manifest
if (loop_cfd->mem()->GetFirstSequenceNumber() == 0 &&
loop_cfd->imm()->NumNotFlushed() == 0) {
loop_cfd->SetLogNumber(logfile_number_);
}
}
}
cfd->mem()->SetNextLogNumber(logfile_number_);
cfd->imm()->Add(cfd->mem(), &context->memtables_to_free_);
new_mem->Ref();
cfd->SetMemtable(new_mem);
context->superversions_to_free_.push_back(InstallSuperVersionAndScheduleWork(
cfd, new_superversion, mutable_cf_options));
return s;
}
#ifndef ROCKSDB_LITE
Status DBImpl::GetPropertiesOfAllTables(ColumnFamilyHandle* column_family,
TablePropertiesCollection* props) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
// Increment the ref count
mutex_.Lock();
auto version = cfd->current();
version->Ref();
mutex_.Unlock();
auto s = version->GetPropertiesOfAllTables(props);
// Decrement the ref count
mutex_.Lock();
version->Unref();
mutex_.Unlock();
return s;
}
Status DBImpl::GetPropertiesOfTablesInRange(ColumnFamilyHandle* column_family,
const Range* range, std::size_t n,
TablePropertiesCollection* props) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
// Increment the ref count
mutex_.Lock();
auto version = cfd->current();
version->Ref();
mutex_.Unlock();
auto s = version->GetPropertiesOfTablesInRange(range, n, props);
// Decrement the ref count
mutex_.Lock();
version->Unref();
mutex_.Unlock();
return s;
}
#endif // ROCKSDB_LITE
const std::string& DBImpl::GetName() const {
return dbname_;
}
Env* DBImpl::GetEnv() const {
return env_;
}
const Options& DBImpl::GetOptions(ColumnFamilyHandle* column_family) const {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
return *cfh->cfd()->options();
}
const DBOptions& DBImpl::GetDBOptions() const { return db_options_; }
bool DBImpl::GetProperty(ColumnFamilyHandle* column_family,
const Slice& property, std::string* value) {
bool is_int_property = false;
bool need_out_of_mutex = false;
DBPropertyType property_type =
GetPropertyType(property, &is_int_property, &need_out_of_mutex);
value->clear();
auto cfd = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family)->cfd();
if (is_int_property) {
uint64_t int_value;
bool ret_value = GetIntPropertyInternal(
cfd, property_type, need_out_of_mutex, false, &int_value);
if (ret_value) {
*value = ToString(int_value);
}
return ret_value;
} else {
InstrumentedMutexLock l(&mutex_);
return cfd->internal_stats()->GetStringProperty(property_type, property,
value);
}
}
bool DBImpl::GetIntProperty(ColumnFamilyHandle* column_family,
const Slice& property, uint64_t* value) {
bool is_int_property = false;
bool need_out_of_mutex = false;
DBPropertyType property_type =
GetPropertyType(property, &is_int_property, &need_out_of_mutex);
if (!is_int_property) {
return false;
}
auto cfd = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family)->cfd();
return GetIntPropertyInternal(cfd, property_type, need_out_of_mutex, false,
value);
}
bool DBImpl::GetIntPropertyInternal(ColumnFamilyData* cfd,
DBPropertyType property_type,
bool need_out_of_mutex, bool is_locked,
uint64_t* value) {
if (!need_out_of_mutex) {
if (is_locked) {
mutex_.AssertHeld();
return cfd->internal_stats()->GetIntProperty(property_type, value, this);
} else {
InstrumentedMutexLock l(&mutex_);
return cfd->internal_stats()->GetIntProperty(property_type, value, this);
}
} else {
SuperVersion* sv = nullptr;
if (!is_locked) {
sv = GetAndRefSuperVersion(cfd);
} else {
sv = cfd->GetSuperVersion();
}
bool ret = cfd->internal_stats()->GetIntPropertyOutOfMutex(
property_type, sv->current, value);
if (!is_locked) {
ReturnAndCleanupSuperVersion(cfd, sv);
}
return ret;
}
}
bool DBImpl::GetAggregatedIntProperty(const Slice& property,
uint64_t* aggregated_value) {
bool need_out_of_mutex;
bool is_int_property;
DBPropertyType property_type =
GetPropertyType(property, &is_int_property, &need_out_of_mutex);
if (!is_int_property) {
return false;
}
uint64_t sum = 0;
{
// Needs mutex to protect the list of column families.
InstrumentedMutexLock l(&mutex_);
uint64_t value;
for (auto* cfd : *versions_->GetColumnFamilySet()) {
if (GetIntPropertyInternal(cfd, property_type, need_out_of_mutex, true,
&value)) {
sum += value;
} else {
return false;
}
}
}
*aggregated_value = sum;
return true;
}
SuperVersion* DBImpl::GetAndRefSuperVersion(ColumnFamilyData* cfd) {
// TODO(ljin): consider using GetReferencedSuperVersion() directly
return cfd->GetThreadLocalSuperVersion(&mutex_);
}
// REQUIRED: this function should only be called on the write thread or if the
// mutex is held.
SuperVersion* DBImpl::GetAndRefSuperVersion(uint32_t column_family_id) {
auto column_family_set = versions_->GetColumnFamilySet();
auto cfd = column_family_set->GetColumnFamily(column_family_id);
if (!cfd) {
return nullptr;
}
return GetAndRefSuperVersion(cfd);
}
// REQUIRED: mutex is NOT held
SuperVersion* DBImpl::GetAndRefSuperVersionUnlocked(uint32_t column_family_id) {
ColumnFamilyData* cfd;
{
InstrumentedMutexLock l(&mutex_);
auto column_family_set = versions_->GetColumnFamilySet();
cfd = column_family_set->GetColumnFamily(column_family_id);
}
if (!cfd) {
return nullptr;
}
return GetAndRefSuperVersion(cfd);
}
void DBImpl::ReturnAndCleanupSuperVersion(ColumnFamilyData* cfd,
SuperVersion* sv) {
bool unref_sv = !cfd->ReturnThreadLocalSuperVersion(sv);
if (unref_sv) {
// Release SuperVersion
if (sv->Unref()) {
{
InstrumentedMutexLock l(&mutex_);
sv->Cleanup();
}
delete sv;
RecordTick(stats_, NUMBER_SUPERVERSION_CLEANUPS);
}
RecordTick(stats_, NUMBER_SUPERVERSION_RELEASES);
}
}
// REQUIRED: this function should only be called on the write thread.
void DBImpl::ReturnAndCleanupSuperVersion(uint32_t column_family_id,
SuperVersion* sv) {
auto column_family_set = versions_->GetColumnFamilySet();
auto cfd = column_family_set->GetColumnFamily(column_family_id);
// If SuperVersion is held, and we successfully fetched a cfd using
// GetAndRefSuperVersion(), it must still exist.
assert(cfd != nullptr);
ReturnAndCleanupSuperVersion(cfd, sv);
}
// REQUIRED: Mutex should NOT be held.
void DBImpl::ReturnAndCleanupSuperVersionUnlocked(uint32_t column_family_id,
SuperVersion* sv) {
ColumnFamilyData* cfd;
{
InstrumentedMutexLock l(&mutex_);
auto column_family_set = versions_->GetColumnFamilySet();
cfd = column_family_set->GetColumnFamily(column_family_id);
}
// If SuperVersion is held, and we successfully fetched a cfd using
// GetAndRefSuperVersion(), it must still exist.
assert(cfd != nullptr);
ReturnAndCleanupSuperVersion(cfd, sv);
}
// REQUIRED: this function should only be called on the write thread or if the
// mutex is held.
ColumnFamilyHandle* DBImpl::GetColumnFamilyHandle(uint32_t column_family_id) {
ColumnFamilyMemTables* cf_memtables = column_family_memtables_.get();
if (!cf_memtables->Seek(column_family_id)) {
return nullptr;
}
return cf_memtables->GetColumnFamilyHandle();
}
// REQUIRED: mutex is NOT held.
ColumnFamilyHandle* DBImpl::GetColumnFamilyHandleUnlocked(
uint32_t column_family_id) {
ColumnFamilyMemTables* cf_memtables = column_family_memtables_.get();
InstrumentedMutexLock l(&mutex_);
if (!cf_memtables->Seek(column_family_id)) {
return nullptr;
}
return cf_memtables->GetColumnFamilyHandle();
}
void DBImpl::GetApproximateSizes(ColumnFamilyHandle* column_family,
const Range* range, int n, uint64_t* sizes,
bool include_memtable) {
Version* v;
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
SuperVersion* sv = GetAndRefSuperVersion(cfd);
v = sv->current;
for (int 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);
sizes[i] = versions_->ApproximateSize(v, k1.Encode(), k2.Encode());
if (include_memtable) {
sizes[i] += sv->mem->ApproximateSize(k1.Encode(), k2.Encode());
sizes[i] += sv->imm->ApproximateSize(k1.Encode(), k2.Encode());
}
}
ReturnAndCleanupSuperVersion(cfd, sv);
}
std::list<uint64_t>::iterator
DBImpl::CaptureCurrentFileNumberInPendingOutputs() {
// We need to remember the iterator of our insert, because after the
// background job is done, we need to remove that element from
// pending_outputs_.
pending_outputs_.push_back(versions_->current_next_file_number());
auto pending_outputs_inserted_elem = pending_outputs_.end();
--pending_outputs_inserted_elem;
return pending_outputs_inserted_elem;
}
void DBImpl::ReleaseFileNumberFromPendingOutputs(
std::list<uint64_t>::iterator v) {
pending_outputs_.erase(v);
}
#ifndef ROCKSDB_LITE
Status DBImpl::GetUpdatesSince(
SequenceNumber seq, unique_ptr<TransactionLogIterator>* iter,
const TransactionLogIterator::ReadOptions& read_options) {
RecordTick(stats_, GET_UPDATES_SINCE_CALLS);
if (seq > versions_->LastSequence()) {
return Status::NotFound("Requested sequence not yet written in the db");
}
return wal_manager_.GetUpdatesSince(seq, iter, read_options, versions_.get());
}
Status DBImpl::DeleteFile(std::string name) {
uint64_t number;
FileType type;
WalFileType log_type;
if (!ParseFileName(name, &number, &type, &log_type) ||
(type != kTableFile && type != kLogFile)) {
Log(InfoLogLevel::ERROR_LEVEL, db_options_.info_log,
"DeleteFile %s failed.\n", name.c_str());
return Status::InvalidArgument("Invalid file name");
}
Status status;
if (type == kLogFile) {
// Only allow deleting archived log files
if (log_type != kArchivedLogFile) {
Log(InfoLogLevel::ERROR_LEVEL, db_options_.info_log,
"DeleteFile %s failed - not archived log.\n",
name.c_str());
return Status::NotSupported("Delete only supported for archived logs");
}
status = env_->DeleteFile(db_options_.wal_dir + "/" + name.c_str());
if (!status.ok()) {
Log(InfoLogLevel::ERROR_LEVEL, db_options_.info_log,
"DeleteFile %s failed -- %s.\n",
name.c_str(), status.ToString().c_str());
}
return status;
}
int level;
FileMetaData* metadata;
ColumnFamilyData* cfd;
VersionEdit edit;
JobContext job_context(next_job_id_.fetch_add(1), true);
{
InstrumentedMutexLock l(&mutex_);
status = versions_->GetMetadataForFile(number, &level, &metadata, &cfd);
if (!status.ok()) {
Log(InfoLogLevel::WARN_LEVEL, db_options_.info_log,
"DeleteFile %s failed. File not found\n", name.c_str());
job_context.Clean();
return Status::InvalidArgument("File not found");
}
assert(level < cfd->NumberLevels());
// If the file is being compacted no need to delete.
if (metadata->being_compacted) {
Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
"DeleteFile %s Skipped. File about to be compacted\n", name.c_str());
job_context.Clean();
return Status::OK();
}
// Only the files in the last level can be deleted externally.
// This is to make sure that any deletion tombstones are not
// lost. Check that the level passed is the last level.
auto* vstoreage = cfd->current()->storage_info();
for (int i = level + 1; i < cfd->NumberLevels(); i++) {
if (vstoreage->NumLevelFiles(i) != 0) {
Log(InfoLogLevel::WARN_LEVEL, db_options_.info_log,
"DeleteFile %s FAILED. File not in last level\n", name.c_str());
job_context.Clean();
return Status::InvalidArgument("File not in last level");
}
}
// if level == 0, it has to be the oldest file
if (level == 0 &&
vstoreage->LevelFiles(0).back()->fd.GetNumber() != number) {
Log(InfoLogLevel::WARN_LEVEL, db_options_.info_log,
"DeleteFile %s failed ---"
" target file in level 0 must be the oldest.", name.c_str());
job_context.Clean();
return Status::InvalidArgument("File in level 0, but not oldest");
}
edit.SetColumnFamily(cfd->GetID());
edit.DeleteFile(level, number);
status = versions_->LogAndApply(cfd, *cfd->GetLatestMutableCFOptions(),
&edit, &mutex_, directories_.GetDbDir());
if (status.ok()) {
InstallSuperVersionAndScheduleWorkWrapper(
cfd, &job_context, *cfd->GetLatestMutableCFOptions());
}
FindObsoleteFiles(&job_context, false);
} // lock released here
LogFlush(db_options_.info_log);
// remove files outside the db-lock
if (job_context.HaveSomethingToDelete()) {
// Call PurgeObsoleteFiles() without holding mutex.
PurgeObsoleteFiles(job_context);
}
job_context.Clean();
return status;
}
Status DBImpl::DeleteFilesInRange(ColumnFamilyHandle* column_family,
const Slice* begin, const Slice* end) {
Status status;
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
ColumnFamilyData* cfd = cfh->cfd();
VersionEdit edit;
std::vector<FileMetaData*> deleted_files;
JobContext job_context(next_job_id_.fetch_add(1), true);
{
InstrumentedMutexLock l(&mutex_);
Version* input_version = cfd->current();
auto* vstorage = input_version->storage_info();
for (int i = 1; i < cfd->NumberLevels(); i++) {
if (vstorage->LevelFiles(i).empty() ||
!vstorage->OverlapInLevel(i, begin, end)) {
continue;
}
std::vector<FileMetaData*> level_files;
InternalKey begin_storage, end_storage, *begin_key, *end_key;
if (begin == nullptr) {
begin_key = nullptr;
} else {
begin_storage.SetMaxPossibleForUserKey(*begin);
begin_key = &begin_storage;
}
if (end == nullptr) {
end_key = nullptr;
} else {
end_storage.SetMinPossibleForUserKey(*end);
end_key = &end_storage;
}
vstorage->GetOverlappingInputs(i, begin_key, end_key, &level_files, -1,
nullptr, false);
FileMetaData* level_file;
for (uint32_t j = 0; j < level_files.size(); j++) {
level_file = level_files[j];
if (((begin == nullptr) ||
(cfd->internal_comparator().user_comparator()->Compare(
level_file->smallest.user_key(), *begin) >= 0)) &&
((end == nullptr) ||
(cfd->internal_comparator().user_comparator()->Compare(
level_file->largest.user_key(), *end) <= 0))) {
if (level_file->being_compacted) {
continue;
}
edit.SetColumnFamily(cfd->GetID());
edit.DeleteFile(i, level_file->fd.GetNumber());
deleted_files.push_back(level_file);
level_file->being_compacted = true;
}
}
}
if (edit.GetDeletedFiles().empty()) {
job_context.Clean();
return Status::OK();
}
input_version->Ref();
status = versions_->LogAndApply(cfd, *cfd->GetLatestMutableCFOptions(),
&edit, &mutex_, directories_.GetDbDir());
if (status.ok()) {
InstallSuperVersionAndScheduleWorkWrapper(
cfd, &job_context, *cfd->GetLatestMutableCFOptions());
}
for (auto* deleted_file : deleted_files) {
deleted_file->being_compacted = false;
}
input_version->Unref();
FindObsoleteFiles(&job_context, false);
} // lock released here
LogFlush(db_options_.info_log);
// remove files outside the db-lock
if (job_context.HaveSomethingToDelete()) {
// Call PurgeObsoleteFiles() without holding mutex.
PurgeObsoleteFiles(job_context);
}
job_context.Clean();
return status;
}
void DBImpl::GetLiveFilesMetaData(std::vector<LiveFileMetaData>* metadata) {
InstrumentedMutexLock l(&mutex_);
versions_->GetLiveFilesMetaData(metadata);
}
void DBImpl::GetColumnFamilyMetaData(
ColumnFamilyHandle* column_family,
ColumnFamilyMetaData* cf_meta) {
assert(column_family);
auto* cfd = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family)->cfd();
auto* sv = GetAndRefSuperVersion(cfd);
sv->current->GetColumnFamilyMetaData(cf_meta);
ReturnAndCleanupSuperVersion(cfd, sv);
}
#endif // ROCKSDB_LITE
Status DBImpl::CheckConsistency() {
mutex_.AssertHeld();
std::vector<LiveFileMetaData> metadata;
versions_->GetLiveFilesMetaData(&metadata);
std::string corruption_messages;
for (const auto& md : metadata) {
// md.name has a leading "/".
std::string file_path = md.db_path + md.name;
uint64_t fsize = 0;
Status s = env_->GetFileSize(file_path, &fsize);
if (!s.ok() &&
env_->GetFileSize(Rocks2LevelTableFileName(file_path), &fsize).ok()) {
s = Status::OK();
}
if (!s.ok()) {
corruption_messages +=
"Can't access " + md.name + ": " + s.ToString() + "\n";
} else if (fsize != md.size) {
corruption_messages += "Sst file size mismatch: " + file_path +
". Size recorded in manifest " +
ToString(md.size) + ", actual size " +
ToString(fsize) + "\n";
}
}
if (corruption_messages.size() == 0) {
return Status::OK();
} else {
return Status::Corruption(corruption_messages);
}
}
Status DBImpl::GetDbIdentity(std::string& identity) const {
std::string idfilename = IdentityFileName(dbname_);
const EnvOptions soptions;
unique_ptr<SequentialFileReader> id_file_reader;
Status s;
{
unique_ptr<SequentialFile> idfile;
s = env_->NewSequentialFile(idfilename, &idfile, soptions);
if (!s.ok()) {
return s;
}
id_file_reader.reset(new SequentialFileReader(std::move(idfile)));
}
uint64_t file_size;
s = env_->GetFileSize(idfilename, &file_size);
if (!s.ok()) {
return s;
}
char* buffer = reinterpret_cast<char*>(alloca(file_size));
Slice id;
s = id_file_reader->Read(static_cast<size_t>(file_size), &id, buffer);
if (!s.ok()) {
return s;
}
identity.assign(id.ToString());
// If last character is '\n' remove it from identity
if (identity.size() > 0 && identity.back() == '\n') {
identity.pop_back();
}
return s;
}
// Default implementations of convenience methods that subclasses of DB
// can call if they wish
Status DB::Put(const WriteOptions& opt, ColumnFamilyHandle* column_family,
const Slice& key, const Slice& value) {
// Pre-allocate size of write batch conservatively.
// 8 bytes are taken by header, 4 bytes for count, 1 byte for type,
// and we allocate 11 extra bytes for key length, as well as value length.
WriteBatch batch(key.size() + value.size() + 24);
batch.Put(column_family, key, value);
return Write(opt, &batch);
}
Status DB::Delete(const WriteOptions& opt, ColumnFamilyHandle* column_family,
const Slice& key) {
WriteBatch batch;
batch.Delete(column_family, key);
return Write(opt, &batch);
}
Status DB::SingleDelete(const WriteOptions& opt,
ColumnFamilyHandle* column_family, const Slice& key) {
WriteBatch batch;
batch.SingleDelete(column_family, key);
return Write(opt, &batch);
}
Status DB::Merge(const WriteOptions& opt, ColumnFamilyHandle* column_family,
const Slice& key, const Slice& value) {
WriteBatch batch;
batch.Merge(column_family, key, value);
return Write(opt, &batch);
}
// Default implementation -- returns not supported status
Status DB::CreateColumnFamily(const ColumnFamilyOptions& cf_options,
const std::string& column_family_name,
ColumnFamilyHandle** handle) {
return Status::NotSupported("");
}
Status DB::DropColumnFamily(ColumnFamilyHandle* column_family) {
return Status::NotSupported("");
}
DB::~DB() { }
Status DB::Open(const Options& options, const std::string& dbname, DB** dbptr) {
DBOptions db_options(options);
ColumnFamilyOptions cf_options(options);
std::vector<ColumnFamilyDescriptor> column_families;
column_families.push_back(
ColumnFamilyDescriptor(kDefaultColumnFamilyName, cf_options));
std::vector<ColumnFamilyHandle*> handles;
Status s = DB::Open(db_options, dbname, column_families, &handles, dbptr);
if (s.ok()) {
assert(handles.size() == 1);
// i can delete the handle since DBImpl is always holding a reference to
// default column family
delete handles[0];
}
return s;
}
Status DB::Open(const DBOptions& db_options, const std::string& dbname,
const std::vector<ColumnFamilyDescriptor>& column_families,
std::vector<ColumnFamilyHandle*>* handles, DB** dbptr) {
Status s = SanitizeOptionsByTable(db_options, column_families);
if (!s.ok()) {
return s;
}
for (auto& cfd : column_families) {
s = CheckCompressionSupported(cfd.options);
if (s.ok() && db_options.allow_concurrent_memtable_write) {
s = CheckConcurrentWritesSupported(cfd.options);
}
if (!s.ok()) {
return s;
}
if (db_options.db_paths.size() > 1) {
if ((cfd.options.compaction_style != kCompactionStyleUniversal) &&
(cfd.options.compaction_style != kCompactionStyleLevel)) {
return Status::NotSupported(
"More than one DB paths are only supported in "
"universal and level compaction styles. ");
}
}
}
if (db_options.db_paths.size() > 4) {
return Status::NotSupported(
"More than four DB paths are not supported yet. ");
}
*dbptr = nullptr;
handles->clear();
size_t max_write_buffer_size = 0;
for (auto cf : column_families) {
max_write_buffer_size =
std::max(max_write_buffer_size, cf.options.write_buffer_size);
}
DBImpl* impl = new DBImpl(db_options, dbname);
s = impl->env_->CreateDirIfMissing(impl->db_options_.wal_dir);
if (s.ok()) {
for (auto db_path : impl->db_options_.db_paths) {
s = impl->env_->CreateDirIfMissing(db_path.path);
if (!s.ok()) {
break;
}
}
}
if (!s.ok()) {
delete impl;
return s;
}
s = impl->CreateArchivalDirectory();
if (!s.ok()) {
delete impl;
return s;
}
impl->mutex_.Lock();
// Handles create_if_missing, error_if_exists
s = impl->Recover(column_families);
if (s.ok()) {
uint64_t new_log_number = impl->versions_->NewFileNumber();
unique_ptr<WritableFile> lfile;
EnvOptions soptions(db_options);
EnvOptions opt_env_options =
impl->db_options_.env->OptimizeForLogWrite(soptions, impl->db_options_);
s = NewWritableFile(impl->db_options_.env,
LogFileName(impl->db_options_.wal_dir, new_log_number),
&lfile, opt_env_options);
if (s.ok()) {
lfile->SetPreallocationBlockSize((max_write_buffer_size / 10) + max_write_buffer_size);
impl->logfile_number_ = new_log_number;
unique_ptr<WritableFileWriter> file_writer(
new WritableFileWriter(std::move(lfile), opt_env_options));
impl->logs_.emplace_back(
new_log_number,
new log::Writer(std::move(file_writer), new_log_number,
impl->db_options_.recycle_log_file_num > 0));
// set column family handles
for (auto cf : column_families) {
auto cfd =
impl->versions_->GetColumnFamilySet()->GetColumnFamily(cf.name);
if (cfd != nullptr) {
handles->push_back(
new ColumnFamilyHandleImpl(cfd, impl, &impl->mutex_));
impl->NewThreadStatusCfInfo(cfd);
} else {
if (db_options.create_missing_column_families) {
// missing column family, create it
ColumnFamilyHandle* handle;
impl->mutex_.Unlock();
s = impl->CreateColumnFamily(cf.options, cf.name, &handle);
impl->mutex_.Lock();
if (s.ok()) {
handles->push_back(handle);
} else {
break;
}
} else {
s = Status::InvalidArgument("Column family not found: ", cf.name);
break;
}
}
}
}
if (s.ok()) {
for (auto cfd : *impl->versions_->GetColumnFamilySet()) {
delete impl->InstallSuperVersionAndScheduleWork(
cfd, nullptr, *cfd->GetLatestMutableCFOptions());
}
impl->alive_log_files_.push_back(
DBImpl::LogFileNumberSize(impl->logfile_number_));
impl->DeleteObsoleteFiles();
s = impl->directories_.GetDbDir()->Fsync();
}
}
if (s.ok()) {
for (auto cfd : *impl->versions_->GetColumnFamilySet()) {
if (cfd->ioptions()->compaction_style == kCompactionStyleFIFO) {
auto* vstorage = cfd->current()->storage_info();
for (int i = 1; i < vstorage->num_levels(); ++i) {
int num_files = vstorage->NumLevelFiles(i);
if (num_files > 0) {
s = Status::InvalidArgument(
"Not all files are at level 0. Cannot "
"open with FIFO compaction style.");
break;
}
}
}
if (!cfd->mem()->IsSnapshotSupported()) {
impl->is_snapshot_supported_ = false;
}
if (cfd->ioptions()->merge_operator != nullptr &&
!cfd->mem()->IsMergeOperatorSupported()) {
s = Status::InvalidArgument(
"The memtable of column family %s does not support merge operator "
"its options.merge_operator is non-null", cfd->GetName().c_str());
}
if (!s.ok()) {
break;
}
}
}
TEST_SYNC_POINT("DBImpl::Open:Opened");
Status persist_options_status;
if (s.ok()) {
// Persist RocksDB Options before scheduling the compaction.
// The WriteOptionsFile() will release and lock the mutex internally.
persist_options_status = impl->WriteOptionsFile();
*dbptr = impl;
impl->opened_successfully_ = true;
impl->MaybeScheduleFlushOrCompaction();
}
impl->mutex_.Unlock();
if (s.ok()) {
Log(InfoLogLevel::INFO_LEVEL, impl->db_options_.info_log, "DB pointer %p",
impl);
LogFlush(impl->db_options_.info_log);
if (!persist_options_status.ok()) {
if (db_options.fail_if_options_file_error) {
s = Status::IOError(
"DB::Open() failed --- Unable to persist Options file",
persist_options_status.ToString());
}
Warn(impl->db_options_.info_log,
"Unable to persist options in DB::Open() -- %s",
persist_options_status.ToString().c_str());
}
}
if (!s.ok()) {
for (auto* h : *handles) {
delete h;
}
handles->clear();
delete impl;
*dbptr = nullptr;
}
return s;
}
Status DB::ListColumnFamilies(const DBOptions& db_options,
const std::string& name,
std::vector<std::string>* column_families) {
return VersionSet::ListColumnFamilies(column_families, name, db_options.env);
}
Snapshot::~Snapshot() {
}
Status DestroyDB(const std::string& dbname, const Options& options) {
const InternalKeyComparator comparator(options.comparator);
const Options& soptions(SanitizeOptions(dbname, &comparator, options));
Env* env = soptions.env;
std::vector<std::string> filenames;
// Ignore error in case directory does not exist
env->GetChildren(dbname, &filenames);
FileLock* lock;
const std::string lockname = LockFileName(dbname);
Status result = env->LockFile(lockname, &lock);
if (result.ok()) {
uint64_t number;
FileType type;
InfoLogPrefix info_log_prefix(!options.db_log_dir.empty(), dbname);
for (size_t i = 0; i < filenames.size(); i++) {
if (ParseFileName(filenames[i], &number, info_log_prefix.prefix, &type) &&
type != kDBLockFile) { // Lock file will be deleted at end
Status del;
std::string path_to_delete = dbname + "/" + filenames[i];
if (type == kMetaDatabase) {
del = DestroyDB(path_to_delete, options);
} else if (type == kTableFile) {
del = DeleteOrMoveToTrash(&options, path_to_delete);
} else {
del = env->DeleteFile(path_to_delete);
}
if (result.ok() && !del.ok()) {
result = del;
}
}
}
for (size_t path_id = 0; path_id < options.db_paths.size(); path_id++) {
const auto& db_path = options.db_paths[path_id];
env->GetChildren(db_path.path, &filenames);
for (size_t i = 0; i < filenames.size(); i++) {
if (ParseFileName(filenames[i], &number, &type) &&
type == kTableFile) { // Lock file will be deleted at end
Status del;
std::string table_path = db_path.path + "/" + filenames[i];
if (path_id == 0) {
del = DeleteOrMoveToTrash(&options, table_path);
} else {
del = env->DeleteFile(table_path);
}
if (result.ok() && !del.ok()) {
result = del;
}
}
}
}
std::vector<std::string> walDirFiles;
std::string archivedir = ArchivalDirectory(dbname);
if (dbname != soptions.wal_dir) {
env->GetChildren(soptions.wal_dir, &walDirFiles);
archivedir = ArchivalDirectory(soptions.wal_dir);
}
// Delete log files in the WAL dir
for (const auto& file : walDirFiles) {
if (ParseFileName(file, &number, &type) && type == kLogFile) {
Status del = env->DeleteFile(soptions.wal_dir + "/" + file);
if (result.ok() && !del.ok()) {
result = del;
}
}
}
std::vector<std::string> archiveFiles;
env->GetChildren(archivedir, &archiveFiles);
// Delete archival files.
for (size_t i = 0; i < archiveFiles.size(); ++i) {
if (ParseFileName(archiveFiles[i], &number, &type) &&
type == kLogFile) {
Status del = env->DeleteFile(archivedir + "/" + archiveFiles[i]);
if (result.ok() && !del.ok()) {
result = del;
}
}
}
// ignore case where no archival directory is present.
env->DeleteDir(archivedir);
env->UnlockFile(lock); // Ignore error since state is already gone
env->DeleteFile(lockname);
env->DeleteDir(dbname); // Ignore error in case dir contains other files
env->DeleteDir(soptions.wal_dir);
}
return result;
}
Status DBImpl::WriteOptionsFile() {
#ifndef ROCKSDB_LITE
mutex_.AssertHeld();
std::vector<std::string> cf_names;
std::vector<ColumnFamilyOptions> cf_opts;
// This part requires mutex to protect the column family options
for (auto cfd : *versions_->GetColumnFamilySet()) {
if (cfd->IsDropped()) {
continue;
}
cf_names.push_back(cfd->GetName());
cf_opts.push_back(BuildColumnFamilyOptions(
*cfd->options(), *cfd->GetLatestMutableCFOptions()));
}
// Unlock during expensive operations. New writes cannot get here
// because the single write thread ensures all new writes get queued.
mutex_.Unlock();
std::string file_name =
TempOptionsFileName(GetName(), versions_->NewFileNumber());
Status s = PersistRocksDBOptions(GetDBOptions(), cf_names, cf_opts, file_name,
GetEnv());
if (s.ok()) {
s = RenameTempFileToOptionsFile(file_name);
}
mutex_.Lock();
return s;
#else
return Status::OK();
#endif // !ROCKSDB_LITE
}
#ifndef ROCKSDB_LITE
namespace {
void DeleteOptionsFilesHelper(const std::map<uint64_t, std::string>& filenames,
const size_t num_files_to_keep,
const std::shared_ptr<Logger>& info_log,
Env* env) {
if (filenames.size() <= num_files_to_keep) {
return;
}
for (auto iter = std::next(filenames.begin(), num_files_to_keep);
iter != filenames.end(); ++iter) {
if (!env->DeleteFile(iter->second).ok()) {
Warn(info_log, "Unable to delete options file %s", iter->second.c_str());
}
}
}
} // namespace
#endif // !ROCKSDB_LITE
Status DBImpl::DeleteObsoleteOptionsFiles() {
#ifndef ROCKSDB_LITE
std::vector<std::string> filenames;
// use ordered map to store keep the filenames sorted from the newest
// to the oldest.
std::map<uint64_t, std::string> options_filenames;
Status s;
s = GetEnv()->GetChildren(GetName(), &filenames);
if (!s.ok()) {
return s;
}
for (auto& filename : filenames) {
uint64_t file_number;
FileType type;
if (ParseFileName(filename, &file_number, &type) && type == kOptionsFile) {
options_filenames.insert(
{std::numeric_limits<uint64_t>::max() - file_number,
GetName() + "/" + filename});
}
}
// Keeps the latest 2 Options file
const size_t kNumOptionsFilesKept = 2;
DeleteOptionsFilesHelper(options_filenames, kNumOptionsFilesKept,
db_options_.info_log, GetEnv());
return Status::OK();
#else
return Status::OK();
#endif // !ROCKSDB_LITE
}
Status DBImpl::RenameTempFileToOptionsFile(const std::string& file_name) {
#ifndef ROCKSDB_LITE
Status s;
std::string options_file_name =
OptionsFileName(GetName(), versions_->NewFileNumber());
// Retry if the file name happen to conflict with an existing one.
s = GetEnv()->RenameFile(file_name, options_file_name);
DeleteObsoleteOptionsFiles();
return s;
#else
return Status::OK();
#endif // !ROCKSDB_LITE
}
#if ROCKSDB_USING_THREAD_STATUS
void DBImpl::NewThreadStatusCfInfo(
ColumnFamilyData* cfd) const {
if (db_options_.enable_thread_tracking) {
ThreadStatusUtil::NewColumnFamilyInfo(this, cfd);
}
}
void DBImpl::EraseThreadStatusCfInfo(
ColumnFamilyData* cfd) const {
if (db_options_.enable_thread_tracking) {
ThreadStatusUtil::EraseColumnFamilyInfo(cfd);
}
}
void DBImpl::EraseThreadStatusDbInfo() const {
if (db_options_.enable_thread_tracking) {
ThreadStatusUtil::EraseDatabaseInfo(this);
}
}
#else
void DBImpl::NewThreadStatusCfInfo(
ColumnFamilyData* cfd) const {
}
void DBImpl::EraseThreadStatusCfInfo(
ColumnFamilyData* cfd) const {
}
void DBImpl::EraseThreadStatusDbInfo() const {
}
#endif // ROCKSDB_USING_THREAD_STATUS
//
// A global method that can dump out the build version
void DumpRocksDBBuildVersion(Logger * log) {
#if !defined(IOS_CROSS_COMPILE)
// if we compile with Xcode, we don't run build_detect_vesion, so we don't
// generate util/build_version.cc
Header(log, "RocksDB version: %d.%d.%d\n", ROCKSDB_MAJOR, ROCKSDB_MINOR,
ROCKSDB_PATCH);
Header(log, "Git sha %s", rocksdb_build_git_sha);
Header(log, "Compile date %s", rocksdb_build_compile_date);
#endif
}
#ifndef ROCKSDB_LITE
SequenceNumber DBImpl::GetEarliestMemTableSequenceNumber(SuperVersion* sv,
bool include_history) {
// Find the earliest sequence number that we know we can rely on reading
// from the memtable without needing to check sst files.
SequenceNumber earliest_seq =
sv->imm->GetEarliestSequenceNumber(include_history);
if (earliest_seq == kMaxSequenceNumber) {
earliest_seq = sv->mem->GetEarliestSequenceNumber();
}
assert(sv->mem->GetEarliestSequenceNumber() >= earliest_seq);
return earliest_seq;
}
#endif // ROCKSDB_LITE
#ifndef ROCKSDB_LITE
Status DBImpl::GetLatestSequenceForKey(SuperVersion* sv, const Slice& key,
bool cache_only, SequenceNumber* seq,
bool* found_record_for_key) {
Status s;
MergeContext merge_context;
SequenceNumber current_seq = versions_->LastSequence();
LookupKey lkey(key, current_seq);
*seq = kMaxSequenceNumber;
*found_record_for_key = false;
// Check if there is a record for this key in the latest memtable
sv->mem->Get(lkey, nullptr, &s, &merge_context, seq);
if (!(s.ok() || s.IsNotFound() || s.IsMergeInProgress())) {
// unexpected error reading memtable.
Log(InfoLogLevel::ERROR_LEVEL, db_options_.info_log,
"Unexpected status returned from MemTable::Get: %s\n",
s.ToString().c_str());
return s;
}
if (*seq != kMaxSequenceNumber) {
// Found a sequence number, no need to check immutable memtables
*found_record_for_key = true;
return Status::OK();
}
// Check if there is a record for this key in the immutable memtables
sv->imm->Get(lkey, nullptr, &s, &merge_context, seq);
if (!(s.ok() || s.IsNotFound() || s.IsMergeInProgress())) {
// unexpected error reading memtable.
Log(InfoLogLevel::ERROR_LEVEL, db_options_.info_log,
"Unexpected status returned from MemTableList::Get: %s\n",
s.ToString().c_str());
return s;
}
if (*seq != kMaxSequenceNumber) {
// Found a sequence number, no need to check memtable history
*found_record_for_key = true;
return Status::OK();
}
// Check if there is a record for this key in the immutable memtables
sv->imm->GetFromHistory(lkey, nullptr, &s, &merge_context, seq);
if (!(s.ok() || s.IsNotFound() || s.IsMergeInProgress())) {
// unexpected error reading memtable.
Log(InfoLogLevel::ERROR_LEVEL, db_options_.info_log,
"Unexpected status returned from MemTableList::GetFromHistory: %s\n",
s.ToString().c_str());
return s;
}
if (*seq != kMaxSequenceNumber) {
// Found a sequence number, no need to check SST files
*found_record_for_key = true;
return Status::OK();
}
// TODO(agiardullo): possible optimization: consider checking cached
// SST files if cache_only=true?
if (!cache_only) {
// Check tables
ReadOptions read_options;
sv->current->Get(read_options, lkey, nullptr, &s, &merge_context,
nullptr /* value_found */, found_record_for_key, seq);
if (!(s.ok() || s.IsNotFound() || s.IsMergeInProgress())) {
// unexpected error reading SST files
Log(InfoLogLevel::ERROR_LEVEL, db_options_.info_log,
"Unexpected status returned from Version::Get: %s\n",
s.ToString().c_str());
return s;
}
}
return Status::OK();
}
#endif // ROCKSDB_LITE
} // namespace rocksdb