[Performance Branch] PlainTable to encode rows with seqID 0, value type using 1 internal byte.

Summary: In PlainTable, use one single byte to represent 8 bytes of internal bytes, if seqID = 0 and it is value type (which should be common for bottom most files). It is to save 7 bytes for uncompressed cases.

Test Plan: make all check

Reviewers: haobo, dhruba, kailiu

Reviewed By: haobo

CC: igor, leveldb

Differential Revision: https://reviews.facebook.net/D15489

db/builder.cc

@@ -26,20 +26,18 @@ namespace rocksdb {
 
 class TableFactory;
 
-TableBuilder* NewTableBuilder(const Options& options, WritableFile* file,
+TableBuilder* NewTableBuilder(const Options& options,
+                              const InternalKeyComparator& internal_comparator,
+                              WritableFile* file,
                               CompressionType compression_type) {
-  return options.table_factory->NewTableBuilder(options, file,
-                                                compression_type);
+  return options.table_factory->NewTableBuilder(options, internal_comparator,
+                                                file, compression_type);
 }
 
-Status BuildTable(const std::string& dbname,
-                  Env* env,
-                  const Options& options,
-                  const EnvOptions& soptions,
-                  TableCache* table_cache,
-                  Iterator* iter,
-                  FileMetaData* meta,
-                  const Comparator* user_comparator,
+Status BuildTable(const std::string& dbname, Env* env, const Options& options,
+                  const EnvOptions& soptions, TableCache* table_cache,
+                  Iterator* iter, FileMetaData* meta,
+                  const InternalKeyComparator& internal_comparator,
                   const SequenceNumber newest_snapshot,
                   const SequenceNumber earliest_seqno_in_memtable,
                   const CompressionType compression) {
@@ -64,7 +62,8 @@ Status BuildTable(const std::string& dbname,
       return s;
     }
 
-    TableBuilder* builder = NewTableBuilder(options, file.get(), compression);
+    TableBuilder* builder =
+        NewTableBuilder(options, internal_comparator, file.get(), compression);
 
     // the first key is the smallest key
     Slice key = iter->key();
@@ -72,8 +71,8 @@ Status BuildTable(const std::string& dbname,
     meta->smallest_seqno = GetInternalKeySeqno(key);
     meta->largest_seqno = meta->smallest_seqno;
 
-    MergeHelper merge(user_comparator, options.merge_operator.get(),
-                      options.info_log.get(),
+    MergeHelper merge(internal_comparator.user_comparator(),
+                      options.merge_operator.get(), options.info_log.get(),
                       true /* internal key corruption is not ok */);
 
     if (purge) {
@@ -102,8 +101,8 @@ Status BuildTable(const std::string& dbname,
         // If the key is the same as the previous key (and it is not the
         // first key), then we skip it, since it is an older version.
         // Otherwise we output the key and mark it as the "new" previous key.
-        if (!is_first_key && !user_comparator->Compare(prev_ikey.user_key,
-                                                       this_ikey.user_key)) {
+        if (!is_first_key && !internal_comparator.user_comparator()->Compare(
+                                  prev_ikey.user_key, this_ikey.user_key)) {
           // seqno within the same key are in decreasing order
           assert(this_ikey.sequence < prev_ikey.sequence);
         } else {
@@ -201,9 +200,8 @@ Status BuildTable(const std::string& dbname,
 
     if (s.ok()) {
       // Verify that the table is usable
-      Iterator* it = table_cache->NewIterator(ReadOptions(),
-                                              soptions,
-                                              *meta);
+      Iterator* it = table_cache->NewIterator(ReadOptions(), soptions,
+                                              internal_comparator, *meta);
       s = it->status();
       delete it;
     }

db/builder.h

@@ -24,22 +24,20 @@ class VersionEdit;
 class TableBuilder;
 class WritableFile;
 
-extern TableBuilder* NewTableBuilder(const Options& options, WritableFile* file,
-                                     CompressionType compression_type);
+extern TableBuilder* NewTableBuilder(
+    const Options& options, const InternalKeyComparator& internal_comparator,
+    WritableFile* file, CompressionType compression_type);
 
 // Build a Table file from the contents of *iter.  The generated file
 // will be named according to meta->number.  On success, the rest of
 // *meta will be filled with metadata about the generated table.
 // If no data is present in *iter, meta->file_size will be set to
 // zero, and no Table file will be produced.
-extern Status BuildTable(const std::string& dbname,
-                         Env* env,
-                         const Options& options,
-                         const EnvOptions& soptions,
-                         TableCache* table_cache,
-                         Iterator* iter,
+extern Status BuildTable(const std::string& dbname, Env* env,
+                         const Options& options, const EnvOptions& soptions,
+                         TableCache* table_cache, Iterator* iter,
                          FileMetaData* meta,
-                         const Comparator* user_comparator,
+                         const InternalKeyComparator& internal_comparator,
                          const SequenceNumber newest_snapshot,
                          const SequenceNumber earliest_seqno_in_memtable,
                          const CompressionType compression);

db/db_impl.cc

@@ -127,7 +127,6 @@ Options SanitizeOptions(const std::string& dbname,
                         const InternalFilterPolicy* ipolicy,
                         const Options& src) {
   Options result = src;
-  result.comparator = icmp;
   result.filter_policy = (src.filter_policy != nullptr) ? ipolicy : nullptr;
   // result.max_open_files means an "infinite" open files.
   if (result.max_open_files != -1) {
@@ -1107,9 +1106,8 @@ Status DBImpl::WriteLevel0TableForRecovery(MemTable* mem, VersionEdit* edit) {
   {
     mutex_.Unlock();
     s = BuildTable(dbname_, env_, options_, storage_options_,
-                   table_cache_.get(), iter, &meta,
-                   user_comparator(), newest_snapshot,
-                   earliest_seqno_in_memtable,
+                   table_cache_.get(), iter, &meta, internal_comparator_,
+                   newest_snapshot, earliest_seqno_in_memtable,
                    GetCompressionFlush(options_));
     LogFlush(options_.info_log);
     mutex_.Lock();
@@ -1173,9 +1171,9 @@ Status DBImpl::WriteLevel0Table(autovector<MemTable*>& mems, VersionEdit* edit,
         (unsigned long)meta.number);
 
     s = BuildTable(dbname_, env_, options_, storage_options_,
-                   table_cache_.get(), iter, &meta,
-                   user_comparator(), newest_snapshot,
-                   earliest_seqno_in_memtable, GetCompressionFlush(options_));
+                   table_cache_.get(), iter, &meta, internal_comparator_,
+                   newest_snapshot, earliest_seqno_in_memtable,
+                   GetCompressionFlush(options_));
     LogFlush(options_.info_log);
     delete iter;
     Log(options_.info_log, "Level-0 flush table #%lu: %lu bytes %s",
@@ -2137,8 +2135,9 @@ Status DBImpl::OpenCompactionOutputFile(CompactionState* compact) {
         options_, compact->compaction->output_level(),
         compact->compaction->enable_compression());
 
-    compact->builder.reset(
-        NewTableBuilder(options_, compact->outfile.get(), compression_type));
+    compact->builder.reset(NewTableBuilder(options_, internal_comparator_,
+                                           compact->outfile.get(),
+                                           compression_type));
   }
   LogFlush(options_.info_log);
   return s;
@@ -2186,9 +2185,8 @@ Status DBImpl::FinishCompactionOutputFile(CompactionState* compact,
   if (s.ok() && current_entries > 0) {
     // Verify that the table is usable
     FileMetaData meta(output_number, current_bytes);
-    Iterator* iter = table_cache_->NewIterator(ReadOptions(),
-                                               storage_options_,
-                                               meta);
+    Iterator* iter = table_cache_->NewIterator(ReadOptions(), storage_options_,
+                                               internal_comparator_, meta);
     s = iter->status();
     delete iter;
     if (s.ok()) {
@@ -2522,8 +2520,7 @@ Status DBImpl::DoCompactionWork(CompactionState* compact,
         // If this is the bottommost level (no files in lower levels)
         // and the earliest snapshot is larger than this seqno
         // then we can squash the seqno to zero.
-        if (options_.compaction_style == kCompactionStyleLevel &&
-            bottommost_level && ikey.sequence < earliest_snapshot &&
+        if (bottommost_level && ikey.sequence < earliest_snapshot &&
             ikey.type != kTypeMerge) {
           assert(ikey.type != kTypeDeletion);
           // make a copy because updating in place would cause problems

db/db_iter.cc

@@ -235,7 +235,7 @@ void DBIter::FindNextUserEntryInternal(bool skipping) {
             valid_ = true;
             MergeValuesNewToOld();  // Go to a different state machine
             return;
-          case kTypeLogData:
+          default:
             assert(false);
             break;
         }

db/db_test.cc

@@ -11,6 +11,7 @@
 #include <set>
 #include <unistd.h>
 
+#include "db/dbformat.h"
 #include "db/db_impl.h"
 #include "db/filename.h"
 #include "db/version_set.h"

db/dbformat.cc

@@ -6,9 +6,9 @@
 // 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/dbformat.h"
 
 #include <stdio.h>
-#include "db/dbformat.h"
 #include "port/port.h"
 #include "util/coding.h"
 #include "util/perf_context_imp.h"
@@ -72,6 +72,28 @@ int InternalKeyComparator::Compare(const Slice& akey, const Slice& bkey) const {
   return r;
 }
 
+int InternalKeyComparator::Compare(const ParsedInternalKey& a,
+                                   const ParsedInternalKey& b) const {
+  // Order by:
+  //    increasing user key (according to user-supplied comparator)
+  //    decreasing sequence number
+  //    decreasing type (though sequence# should be enough to disambiguate)
+  int r = user_comparator_->Compare(a.user_key, b.user_key);
+  BumpPerfCount(&perf_context.user_key_comparison_count);
+  if (r == 0) {
+    if (a.sequence > b.sequence) {
+      r = -1;
+    } else if (a.sequence < b.sequence) {
+      r = +1;
+    } else if (a.type > b.type) {
+      r = -1;
+    } else if (a.type < b.type) {
+      r = +1;
+    }
+  }
+  return r;
+}
+
 void InternalKeyComparator::FindShortestSeparator(
       std::string* start,
       const Slice& limit) const {

db/dbformat.h

@@ -25,12 +25,16 @@ class InternalKey;
 // Value types encoded as the last component of internal keys.
 // DO NOT CHANGE THESE ENUM VALUES: they are embedded in the on-disk
 // data structures.
-enum ValueType {
+// The highest bit of the value type needs to be reserved to SST tables
+// for them to do more flexible encoding.
+enum ValueType : unsigned char {
   kTypeDeletion = 0x0,
   kTypeValue = 0x1,
   kTypeMerge = 0x2,
-  kTypeLogData = 0x3
+  kTypeLogData = 0x3,
+  kMaxValue = 0x7F
 };
+
 // kValueTypeForSeek defines the ValueType that should be passed when
 // constructing a ParsedInternalKey object for seeking to a particular
 // sequence number (since we sort sequence numbers in decreasing order
@@ -96,6 +100,7 @@ class InternalKeyComparator : public Comparator {
     name_("rocksdb.InternalKeyComparator:" +
           std::string(user_comparator_->Name())) {
   }
+  virtual ~InternalKeyComparator() {}
 
   virtual const char* Name() const;
   virtual int Compare(const Slice& a, const Slice& b) const;
@@ -107,6 +112,7 @@ class InternalKeyComparator : public Comparator {
   const Comparator* user_comparator() const { return user_comparator_; }
 
   int Compare(const InternalKey& a, const InternalKey& b) const;
+  int Compare(const ParsedInternalKey& a, const ParsedInternalKey& b) const;
 };
 
 // Filter policy wrapper that converts from internal keys to user keys
@@ -163,6 +169,7 @@ inline bool ParseInternalKey(const Slice& internal_key,
   unsigned char c = num & 0xff;
   result->sequence = num >> 8;
   result->type = static_cast<ValueType>(c);
+  assert(result->type <= ValueType::kMaxValue);
   result->user_key = Slice(internal_key.data(), n - 8);
   return (c <= static_cast<unsigned char>(kValueTypeForSeek));
 }

db/repair.cc

@@ -222,10 +222,8 @@ class Repairer {
     FileMetaData meta;
     meta.number = next_file_number_++;
     Iterator* iter = mem->NewIterator();
-    status = BuildTable(dbname_, env_, options_, storage_options_,
-                        table_cache_, iter, &meta,
-                        icmp_.user_comparator(), 0, 0,
-                        kNoCompression);
+    status = BuildTable(dbname_, env_, options_, storage_options_, table_cache_,
+                        iter, &meta, icmp_, 0, 0, kNoCompression);
     delete iter;
     delete mem->Unref();
     mem = nullptr;
@@ -267,7 +265,7 @@ class Repairer {
     if (status.ok()) {
       FileMetaData dummy_meta(t->meta.number, t->meta.file_size);
       Iterator* iter = table_cache_->NewIterator(
-          ReadOptions(), storage_options_, dummy_meta);
+          ReadOptions(), storage_options_, icmp_, dummy_meta);
       bool empty = true;
       ParsedInternalKey parsed;
       t->min_sequence = 0;

db/simple_table_db_test.cc

@@ -87,10 +87,10 @@ public:
 
   Iterator* NewIterator(const ReadOptions&) override;
 
-  Status Get(
-      const ReadOptions&, const Slice& key, void* arg,
-      bool (*handle_result)(void* arg, const Slice& k, const Slice& v, bool),
-      void (*mark_key_may_exist)(void*) = nullptr) override;
+  Status Get(const ReadOptions&, const Slice& key, void* arg,
+             bool (*handle_result)(void* arg, const ParsedInternalKey& k,
+                                   const Slice& v, bool),
+             void (*mark_key_may_exist)(void*) = nullptr) override;
 
   uint64_t ApproximateOffsetOf(const Slice& key) override;
 
@@ -245,7 +245,8 @@ Status SimpleTableReader::GetOffset(const Slice& target, uint64_t* offset) {
       return s;
     }
 
-    int compare_result = rep_->options.comparator->Compare(tmp_slice, target);
+    InternalKeyComparator ikc(rep_->options.comparator);
+    int compare_result = ikc.Compare(tmp_slice, target);
 
     if (compare_result < 0) {
       if (left == right) {
@@ -280,14 +281,20 @@ Status SimpleTableReader::GetOffset(const Slice& target, uint64_t* offset) {
   return s;
 }
 
-Status SimpleTableReader::Get(
-    const ReadOptions& options, const Slice& k, void* arg,
-    bool (*saver)(void*, const Slice&, const Slice&, bool),
-    void (*mark_key_may_exist)(void*)) {
+Status SimpleTableReader::Get(const ReadOptions& options, const Slice& k,
+                              void* arg,
+                              bool (*saver)(void*, const ParsedInternalKey&,
+                                            const Slice&, bool),
+                              void (*mark_key_may_exist)(void*)) {
   Status s;
   SimpleTableIterator* iter = new SimpleTableIterator(this);
   for (iter->Seek(k); iter->Valid(); iter->Next()) {
-    if (!(*saver)(arg, iter->key(), iter->value(), true)) {
+    ParsedInternalKey parsed_key;
+    if (!ParseInternalKey(iter->key(), &parsed_key)) {
+      return Status::Corruption(Slice());
+    }
+
+    if (!(*saver)(arg, parsed_key, iter->value(), true)) {
       break;
     }
   }
@@ -537,15 +544,19 @@ public:
     return "SimpleTable";
   }
   Status NewTableReader(const Options& options, const EnvOptions& soptions,
+                        const InternalKeyComparator& internal_key,
                         unique_ptr<RandomAccessFile>&& file, uint64_t file_size,
                         unique_ptr<TableReader>* table_reader) const;
 
-  TableBuilder* NewTableBuilder(const Options& options, WritableFile* file,
+  TableBuilder* NewTableBuilder(const Options& options,
+                                const InternalKeyComparator& internal_key,
+                                WritableFile* file,
                                 CompressionType compression_type) const;
 };
 
 Status SimpleTableFactory::NewTableReader(
     const Options& options, const EnvOptions& soptions,
+    const InternalKeyComparator& internal_key,
     unique_ptr<RandomAccessFile>&& file, uint64_t file_size,
     unique_ptr<TableReader>* table_reader) const {
 
@@ -554,8 +565,8 @@ Status SimpleTableFactory::NewTableReader(
 }
 
 TableBuilder* SimpleTableFactory::NewTableBuilder(
-    const Options& options, WritableFile* file,
-    CompressionType compression_type) const {
+    const Options& options, const InternalKeyComparator& internal_key,
+    WritableFile* file, CompressionType compression_type) const {
   return new SimpleTableBuilder(options, file, compression_type);
 }
 

db/table_cache.cc

@@ -60,6 +60,7 @@ void TableCache::ReleaseHandle(Cache::Handle* handle) {
 }
 
 Status TableCache::FindTable(const EnvOptions& toptions,
+                             const InternalKeyComparator& internal_comparator,
                              uint64_t file_number, uint64_t file_size,
                              Cache::Handle** handle, bool* table_io,
                              const bool no_io) {
@@ -84,7 +85,8 @@ Status TableCache::FindTable(const EnvOptions& toptions,
       }
       StopWatch sw(env_, options_->statistics.get(), TABLE_OPEN_IO_MICROS);
       s = options_->table_factory->NewTableReader(
-          *options_, toptions, std::move(file), file_size, &table_reader);
+          *options_, toptions, internal_comparator, std::move(file), file_size,
+          &table_reader);
     }
 
     if (!s.ok()) {
@@ -102,6 +104,7 @@ Status TableCache::FindTable(const EnvOptions& toptions,
 
 Iterator* TableCache::NewIterator(const ReadOptions& options,
                                   const EnvOptions& toptions,
+                                  const InternalKeyComparator& icomparator,
                                   const FileMetaData& file_meta,
                                   TableReader** table_reader_ptr,
                                   bool for_compaction) {
@@ -111,8 +114,8 @@ Iterator* TableCache::NewIterator(const ReadOptions& options,
   Cache::Handle* handle = file_meta.table_reader_handle;
   Status s;
   if (!handle) {
-    s = FindTable(toptions, file_meta.number, file_meta.file_size, &handle,
-                  nullptr, options.read_tier == kBlockCacheTier);
+    s = FindTable(toptions, icomparator, file_meta.number, file_meta.file_size,
+                  &handle, nullptr, options.read_tier == kBlockCacheTier);
   }
   if (!s.ok()) {
     return NewErrorIterator(s);
@@ -135,17 +138,17 @@ Iterator* TableCache::NewIterator(const ReadOptions& options,
 }
 
 Status TableCache::Get(const ReadOptions& options,
-                       const FileMetaData& file_meta,
-                       const Slice& k,
-                       void* arg,
-                       bool (*saver)(void*, const Slice&, const Slice&, bool),
-                       bool* table_io,
-                       void (*mark_key_may_exist)(void*)) {
+                       const InternalKeyComparator& internal_comparator,
+                       const FileMetaData& file_meta, const Slice& k, void* arg,
+                       bool (*saver)(void*, const ParsedInternalKey&,
+                                     const Slice&, bool),
+                       bool* table_io, void (*mark_key_may_exist)(void*)) {
   Cache::Handle* handle = file_meta.table_reader_handle;
   Status s;
   if (!handle) {
-    s = FindTable(storage_options_, file_meta.number, file_meta.file_size,
-                  &handle, table_io, options.read_tier == kBlockCacheTier);
+    s = FindTable(storage_options_, internal_comparator, file_meta.number,
+                  file_meta.file_size, &handle, table_io,
+                  options.read_tier == kBlockCacheTier);
   }
   if (s.ok()) {
     TableReader* t = GetTableReaderFromHandle(handle);
@@ -162,13 +165,12 @@ Status TableCache::Get(const ReadOptions& options,
 }
 
 bool TableCache::PrefixMayMatch(const ReadOptions& options,
-                                uint64_t file_number,
-                                uint64_t file_size,
-                                const Slice& internal_prefix,
-                                bool* table_io) {
+                                const InternalKeyComparator& icomparator,
+                                uint64_t file_number, uint64_t file_size,
+                                const Slice& internal_prefix, bool* table_io) {
   Cache::Handle* handle = nullptr;
-  Status s = FindTable(storage_options_, file_number,
-                       file_size, &handle, table_io);
+  Status s = FindTable(storage_options_, icomparator, file_number, file_size,
+                       &handle, table_io);
   bool may_match = true;
   if (s.ok()) {
     TableReader* t = GetTableReaderFromHandle(handle);

db/table_cache.h

@@ -38,8 +38,8 @@ class TableCache {
   // the returned iterator.  The returned "*tableptr" object is owned by
   // the cache and should not be deleted, and is valid for as long as the
   // returned iterator is live.
-  Iterator* NewIterator(const ReadOptions& options,
-                        const EnvOptions& toptions,
+  Iterator* NewIterator(const ReadOptions& options, const EnvOptions& toptions,
+                        const InternalKeyComparator& internal_comparator,
                         const FileMetaData& file_meta,
                         TableReader** table_reader_ptr = nullptr,
                         bool for_compaction = false);
@@ -48,26 +48,27 @@ class TableCache {
   // call (*handle_result)(arg, found_key, found_value) repeatedly until
   // it returns false.
   Status Get(const ReadOptions& options,
-             const FileMetaData& file_meta,
-             const Slice& k,
-             void* arg,
-             bool (*handle_result)(void*, const Slice&, const Slice&, bool),
-             bool* table_io,
-             void (*mark_key_may_exist)(void*) = nullptr);
+             const InternalKeyComparator& internal_comparator,
+             const FileMetaData& file_meta, const Slice& k, void* arg,
+             bool (*handle_result)(void*, const ParsedInternalKey&,
+                                   const Slice&, bool),
+             bool* table_io, void (*mark_key_may_exist)(void*) = nullptr);
 
   // Determine whether the table may contain the specified prefix.  If
   // the table index or blooms are not in memory, this may cause an I/O
-  bool PrefixMayMatch(const ReadOptions& options, uint64_t file_number,
-                      uint64_t file_size, const Slice& internal_prefix,
-                      bool* table_io);
+  bool PrefixMayMatch(const ReadOptions& options,
+                      const InternalKeyComparator& internal_comparator,
+                      uint64_t file_number, uint64_t file_size,
+                      const Slice& internal_prefix, bool* table_io);
 
   // Evict any entry for the specified file number
   void Evict(uint64_t file_number);
 
   // Find table reader
-  Status FindTable(const EnvOptions& toptions, uint64_t file_number,
-                   uint64_t file_size, Cache::Handle**, bool* table_io=nullptr,
-                   const bool no_io = false);
+  Status FindTable(const EnvOptions& toptions,
+                   const InternalKeyComparator& internal_comparator,
+                   uint64_t file_number, uint64_t file_size, Cache::Handle**,
+                   bool* table_io = nullptr, const bool no_io = false);
 
   // Get TableReader from a cache handle.
   TableReader* GetTableReaderFromHandle(Cache::Handle* handle);

db/table_properties_collector_test.cc

@@ -83,13 +83,13 @@ class DumbLogger : public Logger {
 };
 
 // Utilities test functions
-void MakeBuilder(
-    const Options& options,
-    std::unique_ptr<FakeWritableFile>* writable,
-    std::unique_ptr<TableBuilder>* builder) {
+void MakeBuilder(const Options& options,
+                 const InternalKeyComparator& internal_comparator,
+                 std::unique_ptr<FakeWritableFile>* writable,
+                 std::unique_ptr<TableBuilder>* builder) {
   writable->reset(new FakeWritableFile);
   builder->reset(options.table_factory->NewTableBuilder(
-      options, writable->get(), options.compression));
+      options, internal_comparator, writable->get(), options.compression));
 }
 
 // Collects keys that starts with "A" in a table.
@@ -127,9 +127,8 @@ class RegularKeysStartWithA: public TablePropertiesCollector {
 extern uint64_t kBlockBasedTableMagicNumber;
 extern uint64_t kPlainTableMagicNumber;
 void TestCustomizedTablePropertiesCollector(
-    uint64_t magic_number,
-    bool encode_as_internal,
-    const Options& options) {
+    uint64_t magic_number, bool encode_as_internal, const Options& options,
+    const InternalKeyComparator& internal_comparator) {
   // make sure the entries will be inserted with order.
   std::map<std::string, std::string> kvs = {
     {"About   ", "val5"},  // starts with 'A'
@@ -144,7 +143,7 @@ void TestCustomizedTablePropertiesCollector(
   // -- Step 1: build table
   std::unique_ptr<TableBuilder> builder;
   std::unique_ptr<FakeWritableFile> writable;
-  MakeBuilder(options, &writable, &builder);
+  MakeBuilder(options, internal_comparator, &writable, &builder);
 
   for (const auto& kv : kvs) {
     if (encode_as_internal) {
@@ -193,11 +192,9 @@ TEST(TablePropertiesTest, CustomizedTablePropertiesCollector) {
       options.table_properties_collectors.resize(1);
       options.table_properties_collectors[0].reset(collector);
     }
-    TestCustomizedTablePropertiesCollector(
-        kBlockBasedTableMagicNumber,
-        encode_as_internal,
-        options
-    );
+    test::PlainInternalKeyComparator ikc(options.comparator);
+    TestCustomizedTablePropertiesCollector(kBlockBasedTableMagicNumber,
+                                           encode_as_internal, options, ikc);
   }
 
   // test plain table
@@ -206,9 +203,9 @@ TEST(TablePropertiesTest, CustomizedTablePropertiesCollector) {
       std::make_shared<RegularKeysStartWithA>()
   );
   options.table_factory = std::make_shared<PlainTableFactory>(8, 8, 0);
-  TestCustomizedTablePropertiesCollector(
-      kPlainTableMagicNumber, true, options
-  );
+  test::PlainInternalKeyComparator ikc(options.comparator);
+  TestCustomizedTablePropertiesCollector(kPlainTableMagicNumber, true, options,
+                                         ikc);
 }
 
 void TestInternalKeyPropertiesCollector(
@@ -228,6 +225,8 @@ void TestInternalKeyPropertiesCollector(
   std::unique_ptr<TableBuilder> builder;
   std::unique_ptr<FakeWritableFile> writable;
   Options options;
+  test::PlainInternalKeyComparator pikc(options.comparator);
+
   options.table_factory = table_factory;
   if (sanitized) {
     options.table_properties_collectors = {
@@ -239,12 +238,9 @@ void TestInternalKeyPropertiesCollector(
     // HACK: Set options.info_log to avoid writing log in
     // SanitizeOptions().
     options.info_log = std::make_shared<DumbLogger>();
-    options = SanitizeOptions(
-        "db",  // just a place holder
-        nullptr,  // with skip internal key comparator
-        nullptr,  // don't care filter policy
-        options
-    );
+    options = SanitizeOptions("db",            // just a place holder
+                              &pikc, nullptr,  // don't care filter policy
+                              options);
     options.comparator = comparator;
   } else {
     options.table_properties_collectors = {
@@ -252,7 +248,7 @@ void TestInternalKeyPropertiesCollector(
     };
   }
 
-  MakeBuilder(options, &writable, &builder);
+  MakeBuilder(options, pikc, &writable, &builder);
   for (const auto& k : keys) {
     builder->Add(k.Encode(), "val");
   }

db/version_set.cc

@@ -191,11 +191,10 @@ class Version::LevelFileNumIterator : public Iterator {
   mutable char value_buf_[16];
 };
 
-static Iterator* GetFileIterator(void* arg,
-                                 const ReadOptions& options,
+static Iterator* GetFileIterator(void* arg, const ReadOptions& options,
                                  const EnvOptions& soptions,
-                                 const Slice& file_value,
-                                 bool for_compaction) {
+                                 const InternalKeyComparator& icomparator,
+                                 const Slice& file_value, bool for_compaction) {
   TableCache* cache = reinterpret_cast<TableCache*>(arg);
   if (file_value.size() != 16) {
     return NewErrorIterator(
@@ -210,11 +209,9 @@ static Iterator* GetFileIterator(void* arg,
     }
     FileMetaData meta(DecodeFixed64(file_value.data()),
                       DecodeFixed64(file_value.data() + 8));
-    return cache->NewIterator(options.prefix ? options_copy : options,
-                              soptions,
-                              meta,
-                              nullptr /* don't need reference to table*/,
-                              for_compaction);
+    return cache->NewIterator(
+        options.prefix ? options_copy : options, soptions, icomparator, meta,
+        nullptr /* don't need reference to table*/, for_compaction);
   }
 }
 
@@ -234,10 +231,9 @@ bool Version::PrefixMayMatch(const ReadOptions& options,
     may_match = true;
   } else {
     may_match = vset_->table_cache_->PrefixMayMatch(
-                           options,
-                           DecodeFixed64(level_iter->value().data()),
-                           DecodeFixed64(level_iter->value().data() + 8),
-                           internal_prefix, nullptr);
+        options, vset_->icmp_, DecodeFixed64(level_iter->value().data()),
+        DecodeFixed64(level_iter->value().data() + 8), internal_prefix,
+        nullptr);
   }
   return may_match;
 }
@@ -255,8 +251,8 @@ Iterator* Version::NewConcatenatingIterator(const ReadOptions& options,
       return NewEmptyIterator();
     }
   }
-  return NewTwoLevelIterator(level_iter, &GetFileIterator,
-                             vset_->table_cache_, options, soptions);
+  return NewTwoLevelIterator(level_iter, &GetFileIterator, vset_->table_cache_,
+                             options, soptions, vset_->icmp_);
 }
 
 void Version::AddIterators(const ReadOptions& options,
@@ -265,7 +261,7 @@ void Version::AddIterators(const ReadOptions& options,
   // Merge all level zero files together since they may overlap
   for (const FileMetaData* file : files_[0]) {
     iters->push_back(vset_->table_cache_->NewIterator(options, soptions,
-                                                      *file));
+                                                      vset_->icmp_, *file));
   }
 
   // For levels > 0, we can use a concatenating iterator that sequentially
@@ -315,80 +311,73 @@ static void MarkKeyMayExist(void* arg) {
   }
 }
 
-static bool SaveValue(void* arg, const Slice& ikey, const Slice& v, bool didIO){
+static bool SaveValue(void* arg, const ParsedInternalKey& parsed_key,
+                      const Slice& v, bool didIO) {
   Saver* s = reinterpret_cast<Saver*>(arg);
   MergeContext* merge_contex = s->merge_context;
   std::string merge_result;  // temporary area for merge results later
 
   assert(s != nullptr && merge_contex != nullptr);
 
-  ParsedInternalKey parsed_key;
   // TODO: didIO and Merge?
   s->didIO = didIO;
-  if (!ParseInternalKey(ikey, &parsed_key)) {
-    // TODO: what about corrupt during Merge?
-    s->state = kCorrupt;
-  } else {
-    if (s->ucmp->Compare(parsed_key.user_key, s->user_key) == 0) {
-      // Key matches. Process it
-      switch (parsed_key.type) {
-        case kTypeValue:
-          if (kNotFound == s->state) {
-            s->state = kFound;
-            s->value->assign(v.data(), v.size());
-          } else if (kMerge == s->state) {
-            assert(s->merge_operator != nullptr);
-            s->state = kFound;
-            if (!s->merge_operator->FullMerge(s->user_key, &v,
-                                              merge_contex->GetOperands(),
-                                              s->value, s->logger)) {
-              RecordTick(s->statistics, NUMBER_MERGE_FAILURES);
-              s->state = kCorrupt;
-            }
-          } else {
-            assert(false);
+  if (s->ucmp->Compare(parsed_key.user_key, s->user_key) == 0) {
+    // Key matches. Process it
+    switch (parsed_key.type) {
+      case kTypeValue:
+        if (kNotFound == s->state) {
+          s->state = kFound;
+          s->value->assign(v.data(), v.size());
+        } else if (kMerge == s->state) {
+          assert(s->merge_operator != nullptr);
+          s->state = kFound;
+          if (!s->merge_operator->FullMerge(s->user_key, &v,
+                                            merge_contex->GetOperands(),
+                                            s->value, s->logger)) {
+            RecordTick(s->statistics, NUMBER_MERGE_FAILURES);
+            s->state = kCorrupt;
           }
-          return false;
+        } else {
+          assert(false);
+        }
+        return false;
 
-        case kTypeDeletion:
-          if (kNotFound == s->state) {
-            s->state = kDeleted;
-          } else if (kMerge == s->state) {
-            s->state = kFound;
+      case kTypeDeletion:
+        if (kNotFound == s->state) {
+          s->state = kDeleted;
+        } else if (kMerge == s->state) {
+          s->state = kFound;
           if (!s->merge_operator->FullMerge(s->user_key, nullptr,
                                             merge_contex->GetOperands(),
                                             s->value, s->logger)) {
-              RecordTick(s->statistics, NUMBER_MERGE_FAILURES);
-              s->state = kCorrupt;
-            }
-          } else {
-            assert(false);
-          }
-          return false;
-
-        case kTypeMerge:
-          assert(s->state == kNotFound || s->state == kMerge);
-          s->state = kMerge;
-          merge_contex->PushOperand(v);
-          while (merge_contex->GetNumOperands() >= 2) {
-            // Attempt to merge operands together via user associateive merge
-            if (s->merge_operator->PartialMerge(s->user_key,
-                                                merge_contex->GetOperand(0),
-                                                merge_contex->GetOperand(1),
-                                                &merge_result,
-                                                s->logger)) {
-              merge_contex->PushPartialMergeResult(merge_result);
-            } else {
-              // Associative merge returns false ==> stack the operands
-              break;
-            }
+            RecordTick(s->statistics, NUMBER_MERGE_FAILURES);
+            s->state = kCorrupt;
           }
-          return true;
-
-        case kTypeLogData:
+        } else {
           assert(false);
+        }
+        return false;
+
+      case kTypeMerge:
+        assert(s->state == kNotFound || s->state == kMerge);
+        s->state = kMerge;
+        merge_contex->PushOperand(v);
+        while (merge_contex->GetNumOperands() >= 2) {
+          // Attempt to merge operands together via user associateive merge
+          if (s->merge_operator->PartialMerge(
+                  s->user_key, merge_contex->GetOperand(0),
+                  merge_contex->GetOperand(1), &merge_result, s->logger)) {
+            merge_contex->PushPartialMergeResult(merge_result);
+          } else {
+            // Associative merge returns false ==> stack the operands
           break;
+          }
       }
+      return true;
+
+      default:
+        assert(false);
+        break;
     }
   }
 
@@ -521,8 +510,9 @@ void Version::Get(const ReadOptions& options,
       prev_file = f;
 #endif
       bool tableIO = false;
-      *status = vset_->table_cache_->Get(options, *f, ikey, &saver, SaveValue,
-                                         &tableIO, MarkKeyMayExist);
+      *status =
+          vset_->table_cache_->Get(options, vset_->icmp_, *f, ikey, &saver,
+                                   SaveValue, &tableIO, MarkKeyMayExist);
       // TODO: examine the behavior for corrupted key
       if (!status->ok()) {
         return;
@@ -1355,9 +1345,8 @@ class VersionSet::Builder {
       for (auto& file_meta : *(levels_[level].added_files)) {
         assert (!file_meta->table_reader_handle);
         bool table_io;
-        vset_->table_cache_->FindTable(vset_->storage_options_,
-                                       file_meta->number,
-                                       file_meta->file_size,
+        vset_->table_cache_->FindTable(vset_->storage_options_, vset_->icmp_,
+                                       file_meta->number, file_meta->file_size,
                                        &file_meta->table_reader_handle,
                                        &table_io, false);
       }
@@ -2069,8 +2058,9 @@ uint64_t VersionSet::ApproximateOffsetOf(Version* v, const InternalKey& ikey) {
         // "ikey" falls in the range for this table.  Add the
         // approximate offset of "ikey" within the table.
         TableReader* table_reader_ptr;
-        Iterator* iter = table_cache_->NewIterator(
-            ReadOptions(), storage_options_, *(files[i]), &table_reader_ptr);
+        Iterator* iter =
+            table_cache_->NewIterator(ReadOptions(), storage_options_, icmp_,
+                                      *(files[i]), &table_reader_ptr);
         if (table_reader_ptr != nullptr) {
           result += table_reader_ptr->ApproximateOffsetOf(ikey.Encode());
         }
@@ -2134,14 +2124,14 @@ Iterator* VersionSet::MakeInputIterator(Compaction* c) {
       if (c->level() + which == 0) {
         for (const auto& file : *c->inputs(which)) {
           list[num++] = table_cache_->NewIterator(
-              options, storage_options_compactions_, *file, nullptr,
+              options, storage_options_compactions_, icmp_, *file, nullptr,
               true /* for compaction */);
         }
       } else {
         // Create concatenating iterator for the files from this level
         list[num++] = NewTwoLevelIterator(
             new Version::LevelFileNumIterator(icmp_, c->inputs(which)),
-            &GetFileIterator, table_cache_, options, storage_options_,
+            &GetFileIterator, table_cache_, options, storage_options_, icmp_,
             true /* for compaction */);
       }
     }

db/write_batch_test.cc

@@ -57,7 +57,7 @@ static std::string PrintContents(WriteBatch* b) {
         state.append(")");
         count++;
         break;
-      case kTypeLogData:
+      default:
         assert(false);
         break;
     }

include/rocksdb/options.h

@@ -34,6 +34,7 @@ class TablePropertiesCollector;
 class Slice;
 class SliceTransform;
 class Statistics;
+class InternalKeyComparator;
 
 using std::shared_ptr;
 

include/rocksdb/table.h

@@ -27,8 +27,6 @@
 
 namespace rocksdb {
 
-class TableFactory;
-
 // -- Block-based Table
 class FlushBlockPolicyFactory;
 

table/block_based_table_builder.cc

@@ -21,6 +21,7 @@
 #include "rocksdb/env.h"
 #include "rocksdb/filter_policy.h"
 #include "rocksdb/options.h"
+#include "db/dbformat.h"
 #include "table/block_based_table_reader.h"
 #include "table/block.h"
 #include "table/block_builder.h"
@@ -52,6 +53,7 @@ extern const uint64_t kBlockBasedTableMagicNumber
 
 struct BlockBasedTableBuilder::Rep {
   Options options;
+  const InternalKeyComparator& internal_comparator;
   WritableFile* file;
   uint64_t offset = 0;
   Status status;
@@ -71,31 +73,30 @@ struct BlockBasedTableBuilder::Rep {
   std::string compressed_output;
   std::unique_ptr<FlushBlockPolicy> flush_block_policy;
 
-  Rep(const Options& opt,
-      WritableFile* f,
-      FlushBlockPolicyFactory* flush_block_policy_factory,
+  Rep(const Options& opt, const InternalKeyComparator& icomparator,
+      WritableFile* f, FlushBlockPolicyFactory* flush_block_policy_factory,
       CompressionType compression_type)
       : options(opt),
+        internal_comparator(icomparator),
         file(f),
-        data_block(options),
+        data_block(options, &internal_comparator),
         // To avoid linear scan, we make the block_restart_interval to be `1`
         // in index block builder
-        index_block(1 /* block_restart_interval */, options.comparator),
+        index_block(1 /* block_restart_interval */, &internal_comparator),
         compression_type(compression_type),
-        filter_block(opt.filter_policy == nullptr ? nullptr
-                     : new FilterBlockBuilder(opt)),
+        filter_block(opt.filter_policy == nullptr
+                         ? nullptr
+                         : new FilterBlockBuilder(opt, &internal_comparator)),
         flush_block_policy(
-            flush_block_policy_factory->NewFlushBlockPolicy(data_block)) {
-  }
+            flush_block_policy_factory->NewFlushBlockPolicy(data_block)) {}
 };
 
 BlockBasedTableBuilder::BlockBasedTableBuilder(
-    const Options& options,
-    WritableFile* file,
-    FlushBlockPolicyFactory* flush_block_policy_factory,
+    const Options& options, const InternalKeyComparator& internal_comparator,
+    WritableFile* file, FlushBlockPolicyFactory* flush_block_policy_factory,
     CompressionType compression_type)
-    : rep_(new Rep(options,
-                   file, flush_block_policy_factory, compression_type)) {
+    : rep_(new Rep(options, internal_comparator, file,
+                   flush_block_policy_factory, compression_type)) {
   if (rep_->filter_block != nullptr) {
     rep_->filter_block->StartBlock(0);
   }
@@ -118,7 +119,7 @@ void BlockBasedTableBuilder::Add(const Slice& key, const Slice& value) {
   assert(!r->closed);
   if (!ok()) return;
   if (r->props.num_entries > 0) {
-    assert(r->options.comparator->Compare(key, Slice(r->last_key)) > 0);
+    assert(r->internal_comparator.Compare(key, Slice(r->last_key)) > 0);
   }
 
   auto should_flush = r->flush_block_policy->Update(key, value);
@@ -135,7 +136,7 @@ void BlockBasedTableBuilder::Add(const Slice& key, const Slice& value) {
     // entries in the first block and < all entries in subsequent
     // blocks.
     if (ok()) {
-      r->options.comparator->FindShortestSeparator(&r->last_key, key);
+      r->internal_comparator.FindShortestSeparator(&r->last_key, key);
       std::string handle_encoding;
       r->pending_handle.EncodeTo(&handle_encoding);
       r->index_block.Add(r->last_key, Slice(handle_encoding));
@@ -339,7 +340,7 @@ Status BlockBasedTableBuilder::Finish() {
   // block, we will finish writing all index entries here and flush them
   // to storage after metaindex block is written.
   if (ok() && !empty_data_block) {
-    r->options.comparator->FindShortSuccessor(&r->last_key);
+    r->internal_comparator.FindShortSuccessor(&r->last_key);
 
     std::string handle_encoding;
     r->pending_handle.EncodeTo(&handle_encoding);

table/block_based_table_builder.h

@@ -26,6 +26,7 @@ class BlockBasedTableBuilder : public TableBuilder {
   // building in *file.  Does not close the file.  It is up to the
   // caller to close the file after calling Finish().
   BlockBasedTableBuilder(const Options& options,
+                         const InternalKeyComparator& internal_comparator,
                          WritableFile* file,
                          FlushBlockPolicyFactory* flush_block_policy_factory,
                          CompressionType compression_type);

table/block_based_table_factory.cc

@@ -20,15 +20,17 @@ namespace rocksdb {
 
 Status BlockBasedTableFactory::NewTableReader(
     const Options& options, const EnvOptions& soptions,
+    const InternalKeyComparator& internal_comparator,
     unique_ptr<RandomAccessFile>&& file, uint64_t file_size,
     unique_ptr<TableReader>* table_reader) const {
   return BlockBasedTable::Open(options, soptions, table_options_,
-                               std::move(file), file_size, table_reader);
+                               internal_comparator, std::move(file), file_size,
+                               table_reader);
 }
 
 TableBuilder* BlockBasedTableFactory::NewTableBuilder(
-    const Options& options, WritableFile* file,
-    CompressionType compression_type) const {
+    const Options& options, const InternalKeyComparator& internal_comparator,
+    WritableFile* file, CompressionType compression_type) const {
   auto flush_block_policy_factory = 
     table_options_.flush_block_policy_factory.get();
 
@@ -45,11 +47,9 @@ TableBuilder* BlockBasedTableFactory::NewTableBuilder(
                                           options.block_size_deviation);
   }
 
-  auto table_builder =  new BlockBasedTableBuilder(
-      options,
-      file,
-      flush_block_policy_factory,
-      compression_type);
+  auto table_builder =
+      new BlockBasedTableBuilder(options, internal_comparator, file,
+                                 flush_block_policy_factory, compression_type);
 
   // Delete flush_block_policy_factory only when it's just created from the
   // options.

table/block_based_table_factory.h

@@ -35,12 +35,13 @@ class BlockBasedTableFactory : public TableFactory {
   const char* Name() const override { return "BlockBasedTable"; }
 
   Status NewTableReader(const Options& options, const EnvOptions& soptions,
+                        const InternalKeyComparator& internal_comparator,
                         unique_ptr<RandomAccessFile>&& file, uint64_t file_size,
                         unique_ptr<TableReader>* table_reader) const override;
 
-  TableBuilder* NewTableBuilder(const Options& options, WritableFile* file,
-                                CompressionType compression_type)
-      const override;
+  TableBuilder* NewTableBuilder(
+      const Options& options, const InternalKeyComparator& internal_comparator,
+      WritableFile* file, CompressionType compression_type) const override;
 
  private:
   BlockBasedTableOptions table_options_;

table/block_based_table_reader.cc

@@ -39,12 +39,13 @@ const size_t kMaxCacheKeyPrefixSize = kMaxVarint64Length*3+1;
 using std::unique_ptr;
 
 struct BlockBasedTable::Rep {
-  Rep(const EnvOptions& storage_options) :
-    soptions(storage_options) {
-  }
+  Rep(const EnvOptions& storage_options,
+      const InternalKeyComparator& internal_comparator)
+      : soptions(storage_options), internal_comparator_(internal_comparator) {}
 
   Options options;
   const EnvOptions& soptions;
+  const InternalKeyComparator& internal_comparator_;
   Status status;
   unique_ptr<RandomAccessFile> file;
   char cache_key_prefix[kMaxCacheKeyPrefixSize];
@@ -225,6 +226,7 @@ Cache::Handle* GetFromBlockCache(
 
 Status BlockBasedTable::Open(const Options& options, const EnvOptions& soptions,
                              const BlockBasedTableOptions& table_options,
+                             const InternalKeyComparator& internal_comparator,
                              unique_ptr<RandomAccessFile>&& file,
                              uint64_t file_size,
                              unique_ptr<TableReader>* table_reader) {
@@ -236,7 +238,7 @@ Status BlockBasedTable::Open(const Options& options, const EnvOptions& soptions,
 
   // We've successfully read the footer and the index block: we're
   // ready to serve requests.
-  Rep* rep = new BlockBasedTable::Rep(soptions);
+  Rep* rep = new BlockBasedTable::Rep(soptions, internal_comparator);
   rep->options = options;
   rep->file = std::move(file);
   rep->metaindex_handle = footer.metaindex_handle();
@@ -661,7 +663,7 @@ Iterator* BlockBasedTable::BlockReader(void* arg,
 
   Iterator* iter;
   if (block != nullptr) {
-    iter = block->NewIterator(table->rep_->options.comparator);
+    iter = block->NewIterator(&(table->rep_->internal_comparator_));
     if (cache_handle != nullptr) {
       iter->RegisterCleanup(&ReleaseBlock, block_cache, cache_handle);
     } else {
@@ -734,7 +736,7 @@ BlockBasedTable::GetFilter(bool no_io) const {
 // Get the iterator from the index block.
 Iterator* BlockBasedTable::IndexBlockReader(const ReadOptions& options) const {
   if (rep_->index_block) {
-    return rep_->index_block->NewIterator(rep_->options.comparator);
+    return rep_->index_block->NewIterator(&(rep_->internal_comparator_));
   }
 
   // get index block from cache
@@ -755,7 +757,7 @@ Iterator* BlockBasedTable::IndexBlockReader(const ReadOptions& options) const {
 
   Iterator* iter;
   if (entry.value != nullptr) {
-    iter = entry.value->NewIterator(rep_->options.comparator);
+    iter = entry.value->NewIterator(&(rep_->internal_comparator_));
     if (entry.cache_handle) {
       iter->RegisterCleanup(
           &ReleaseBlock, rep_->options.block_cache.get(), entry.cache_handle
@@ -769,9 +771,9 @@ Iterator* BlockBasedTable::IndexBlockReader(const ReadOptions& options) const {
   return iter;
 }
 
-Iterator* BlockBasedTable::BlockReader(void* arg,
-                                       const ReadOptions& options,
+Iterator* BlockBasedTable::BlockReader(void* arg, const ReadOptions& options,
                                        const EnvOptions& soptions,
+                                       const InternalKeyComparator& icomparator,
                                        const Slice& index_value,
                                        bool for_compaction) {
   return BlockReader(arg, options, index_value, nullptr, for_compaction);
@@ -862,20 +864,15 @@ Iterator* BlockBasedTable::NewIterator(const ReadOptions& options) {
     }
   }
 
-  return NewTwoLevelIterator(
-           IndexBlockReader(options),
-           &BlockBasedTable::BlockReader,
-           const_cast<BlockBasedTable*>(this),
-           options,
-           rep_->soptions
-         );
+  return NewTwoLevelIterator(IndexBlockReader(options),
+                             &BlockBasedTable::BlockReader,
+                             const_cast<BlockBasedTable*>(this), options,
+                             rep_->soptions, rep_->internal_comparator_);
 }
 
 Status BlockBasedTable::Get(
-    const ReadOptions& readOptions,
-    const Slice& key,
-    void* handle_context,
-    bool (*result_handler)(void* handle_context, const Slice& k,
+    const ReadOptions& readOptions, const Slice& key, void* handle_context,
+    bool (*result_handler)(void* handle_context, const ParsedInternalKey& k,
                            const Slice& v, bool didIO),
     void (*mark_key_may_exist_handler)(void* handle_context)) {
   Status s;
@@ -913,8 +910,13 @@ Status BlockBasedTable::Get(
 
       // Call the *saver function on each entry/block until it returns false
       for (block_iter->Seek(key); block_iter->Valid(); block_iter->Next()) {
-        if (!(*result_handler)(handle_context, block_iter->key(),
-                               block_iter->value(), didIO)) {
+        ParsedInternalKey parsed_key;
+        if (!ParseInternalKey(block_iter->key(), &parsed_key)) {
+          s = Status::Corruption(Slice());
+        }
+
+        if (!(*result_handler)(handle_context, parsed_key, block_iter->value(),
+                               didIO)) {
           done = true;
           break;
         }
@@ -931,7 +933,8 @@ Status BlockBasedTable::Get(
   return s;
 }
 
-bool SaveDidIO(void* arg, const Slice& key, const Slice& value, bool didIO) {
+bool SaveDidIO(void* arg, const ParsedInternalKey& key, const Slice& value,
+               bool didIO) {
   *reinterpret_cast<bool*>(arg) = didIO;
   return false;
 }

table/block_based_table_reader.h

@@ -51,6 +51,7 @@ class BlockBasedTable : public TableReader {
   // *file must remain live while this Table is in use.
   static Status Open(const Options& db_options, const EnvOptions& env_options,
                      const BlockBasedTableOptions& table_options,
+                     const InternalKeyComparator& internal_key_comparator,
                      unique_ptr<RandomAccessFile>&& file, uint64_t file_size,
                      unique_ptr<TableReader>* table_reader);
 
@@ -63,10 +64,11 @@ class BlockBasedTable : public TableReader {
 
   Status Get(const ReadOptions& readOptions, const Slice& key,
              void* handle_context,
-             bool (*result_handler)(void* handle_context, const Slice& k,
-                                    const Slice& v, bool didIO),
-             void (*mark_key_may_exist_handler)(void* handle_context) = nullptr)
-      override;
+             bool (*result_handler)(void* handle_context,
+                                    const ParsedInternalKey& k, const Slice& v,
+                                    bool didIO),
+             void (*mark_key_may_exist_handler)(void* handle_context) =
+                 nullptr) override;
 
   // Given a key, return an approximate byte offset in the file where
   // the data for that key begins (or would begin if the key were
@@ -97,8 +99,9 @@ class BlockBasedTable : public TableReader {
   bool compaction_optimized_;
 
   static Iterator* BlockReader(void*, const ReadOptions&,
-                               const EnvOptions& soptions, const Slice&,
-                               bool for_compaction);
+                               const EnvOptions& soptions,
+                               const InternalKeyComparator& icomparator,
+                               const Slice&, bool for_compaction);
 
   static Iterator* BlockReader(void*, const ReadOptions&, const Slice&,
                                bool* didIO, bool for_compaction = false);

table/block_builder.cc

@@ -36,6 +36,7 @@
 #include <algorithm>
 #include <assert.h>
 #include "rocksdb/comparator.h"
+#include "db/dbformat.h"
 #include "util/coding.h"
 
 namespace rocksdb {
@@ -51,9 +52,8 @@ BlockBuilder::BlockBuilder(int block_restart_interval,
   restarts_.push_back(0);       // First restart point is at offset 0
 }
 
-BlockBuilder::BlockBuilder(const Options& options)
-    : BlockBuilder(options.block_restart_interval, options.comparator) {
-}
+BlockBuilder::BlockBuilder(const Options& options, const Comparator* comparator)
+    : BlockBuilder(options.block_restart_interval, comparator) {}
 
 void BlockBuilder::Reset() {
   buffer_.clear();

table/block_builder.h

@@ -21,7 +21,7 @@ class Comparator;
 class BlockBuilder {
  public:
   BlockBuilder(int block_builder, const Comparator* comparator);
-  explicit BlockBuilder(const Options& options);
+  explicit BlockBuilder(const Options& options, const Comparator* comparator);
 
   // Reset the contents as if the BlockBuilder was just constructed.
   void Reset();

table/block_test.cc

@@ -32,9 +32,12 @@ class BlockTest {};
 TEST(BlockTest, SimpleTest) {
   Random rnd(301);
   Options options = Options();
+  std::unique_ptr<InternalKeyComparator> ic;
+  ic.reset(new test::PlainInternalKeyComparator(options.comparator));
+
   std::vector<std::string> keys;
   std::vector<std::string> values;
-  BlockBuilder builder(options);
+  BlockBuilder builder(options, ic.get());
   int num_records = 100000;
   char buf[10];
   char* p = &buf[0];

table/filter_block.cc

@@ -21,11 +21,12 @@ namespace rocksdb {
 static const size_t kFilterBaseLg = 11;
 static const size_t kFilterBase = 1 << kFilterBaseLg;
 
-FilterBlockBuilder::FilterBlockBuilder(const Options& opt)
-                 : policy_(opt.filter_policy),
-                   prefix_extractor_(opt.prefix_extractor),
-                   whole_key_filtering_(opt.whole_key_filtering),
-                   comparator_(opt.comparator){}
+FilterBlockBuilder::FilterBlockBuilder(const Options& opt,
+                                       const Comparator* internal_comparator)
+    : policy_(opt.filter_policy),
+      prefix_extractor_(opt.prefix_extractor),
+      whole_key_filtering_(opt.whole_key_filtering),
+      comparator_(internal_comparator) {}
 
 void FilterBlockBuilder::StartBlock(uint64_t block_offset) {
   uint64_t filter_index = (block_offset / kFilterBase);

table/filter_block.h

@@ -35,7 +35,8 @@ class FilterPolicy;
 //      (StartBlock AddKey*)* Finish
 class FilterBlockBuilder {
  public:
-  explicit FilterBlockBuilder(const Options& opt);
+  explicit FilterBlockBuilder(const Options& opt,
+                              const Comparator* internal_comparator);
 
   void StartBlock(uint64_t block_offset);
   void AddKey(const Slice& key);

table/filter_block_test.cc

@@ -55,7 +55,7 @@ class FilterBlockTest {
 };
 
 TEST(FilterBlockTest, EmptyBuilder) {
-  FilterBlockBuilder builder(options_);
+  FilterBlockBuilder builder(options_, options_.comparator);
   Slice block = builder.Finish();
   ASSERT_EQ("\\x00\\x00\\x00\\x00\\x0b", EscapeString(block));
   FilterBlockReader reader(options_, block);
@@ -64,7 +64,7 @@ TEST(FilterBlockTest, EmptyBuilder) {
 }
 
 TEST(FilterBlockTest, SingleChunk) {
-  FilterBlockBuilder builder(options_);
+  FilterBlockBuilder builder(options_, options_.comparator);
   builder.StartBlock(100);
   builder.AddKey("foo");
   builder.AddKey("bar");
@@ -85,7 +85,7 @@ TEST(FilterBlockTest, SingleChunk) {
 }
 
 TEST(FilterBlockTest, MultiChunk) {
-  FilterBlockBuilder builder(options_);
+  FilterBlockBuilder builder(options_, options_.comparator);
 
   // First filter
   builder.StartBlock(0);

table/plain_table_builder.cc

@@ -11,6 +11,8 @@
 #include "rocksdb/env.h"
 #include "rocksdb/filter_policy.h"
 #include "rocksdb/options.h"
+#include "table/plain_table_factory.h"
+#include "db/dbformat.h"
 #include "table/block_builder.h"
 #include "table/filter_block.h"
 #include "table/format.h"
@@ -67,20 +69,32 @@ PlainTableBuilder::~PlainTableBuilder() {
 }
 
 void PlainTableBuilder::Add(const Slice& key, const Slice& value) {
-  assert(user_key_len_ == 0 || key.size() == user_key_len_ + 8);
+  size_t user_key_size = key.size() - 8;
+  assert(user_key_len_ == 0 || user_key_size == user_key_len_);
 
   if (!IsFixedLength()) {
     // Write key length
-    int key_size = key.size();
     key_size_str_.clear();
-    PutVarint32(&key_size_str_, key_size);
+    PutVarint32(&key_size_str_, user_key_size);
     file_->Append(key_size_str_);
     offset_ += key_size_str_.length();
   }
 
   // Write key
-  file_->Append(key);
-  offset_ += key.size();
+  ParsedInternalKey parsed_key;
+  if (!ParseInternalKey(key, &parsed_key)) {
+    status_ = Status::Corruption(Slice());
+    return;
+  }
+  if (parsed_key.sequence == 0 && parsed_key.type == kTypeValue) {
+    file_->Append(Slice(key.data(), user_key_size));
+    char tmp_char = PlainTableFactory::kValueTypeSeqId0;
+    file_->Append(Slice(&tmp_char, 1));
+    offset_ += key.size() - 7;
+  } else {
+    file_->Append(key);
+    offset_ += key.size();
+  }
 
   // Write value length
   value_size_str_.clear();
@@ -105,9 +119,7 @@ void PlainTableBuilder::Add(const Slice& key, const Slice& value) {
   );
 }
 
-Status PlainTableBuilder::status() const {
-  return Status::OK();
-}
+Status PlainTableBuilder::status() const { return status_; }
 
 Status PlainTableBuilder::Finish() {
   assert(!closed_);

table/plain_table_factory.cc

@@ -6,6 +6,7 @@
 
 #include <memory>
 #include <stdint.h>
+#include "db/dbformat.h"
 #include "table/plain_table_builder.h"
 #include "table/plain_table_reader.h"
 #include "port/port.h"
@@ -14,16 +15,18 @@ namespace rocksdb {
 
 Status PlainTableFactory::NewTableReader(const Options& options,
                                          const EnvOptions& soptions,
+                                         const InternalKeyComparator& icomp,
                                          unique_ptr<RandomAccessFile>&& file,
                                          uint64_t file_size,
                                          unique_ptr<TableReader>* table) const {
-  return PlainTableReader::Open(options, soptions, std::move(file), file_size,
-                                table, bloom_bits_per_key_, hash_table_ratio_);
+  return PlainTableReader::Open(options, soptions, icomp, std::move(file),
+                                file_size, table, bloom_bits_per_key_,
+                                hash_table_ratio_);
 }
 
 TableBuilder* PlainTableFactory::NewTableBuilder(
-    const Options& options, WritableFile* file,
-    CompressionType compression_type) const {
+    const Options& options, const InternalKeyComparator& internal_comparator,
+    WritableFile* file, CompressionType compression_type) const {
   return new PlainTableBuilder(options, file, user_key_len_);
 }
 

table/plain_table_factory.h

@@ -57,12 +57,16 @@ class PlainTableFactory : public TableFactory {
         hash_table_ratio_(hash_table_ratio) {}
   const char* Name() const override { return "PlainTable"; }
   Status NewTableReader(const Options& options, const EnvOptions& soptions,
+                        const InternalKeyComparator& internal_comparator,
                         unique_ptr<RandomAccessFile>&& file, uint64_t file_size,
                         unique_ptr<TableReader>* table) const override;
+  TableBuilder* NewTableBuilder(const Options& options,
+                                const InternalKeyComparator& icomparator,
+                                WritableFile* file,
+                                CompressionType compression_type) const
+      override;
 
-  TableBuilder* NewTableBuilder(const Options& options, WritableFile* file,
-                                CompressionType compression_type)
-      const override;
+  static const char kValueTypeSeqId0 = 0xFF;
 
  private:
   uint32_t user_key_len_;

table/plain_table_reader.cc

@@ -4,8 +4,7 @@
 
 #include "table/plain_table_reader.h"
 
-#include <unordered_map>
-#include <map>
+#include <string>
 
 #include "db/dbformat.h"
 
@@ -77,6 +76,7 @@ class PlainTableIterator : public Iterator {
   Slice key_;
   Slice value_;
   Status status_;
+  std::string tmp_str_;
   // No copying allowed
   PlainTableIterator(const PlainTableIterator&) = delete;
   void operator=(const Iterator&) = delete;
@@ -84,10 +84,12 @@ class PlainTableIterator : public Iterator {
 
 extern const uint64_t kPlainTableMagicNumber;
 PlainTableReader::PlainTableReader(const EnvOptions& storage_options,
+                                   const InternalKeyComparator& icomparator,
                                    uint64_t file_size, int bloom_bits_per_key,
                                    double hash_table_ratio,
                                    const TableProperties& table_properties)
     : soptions_(storage_options),
+      internal_comparator_(icomparator),
       file_size_(file_size),
       kHashTableRatio(hash_table_ratio),
       kBloomBitsPerKey(bloom_bits_per_key),
@@ -103,6 +105,7 @@ PlainTableReader::~PlainTableReader() {
 
 Status PlainTableReader::Open(const Options& options,
                               const EnvOptions& soptions,
+                              const InternalKeyComparator& internal_comparator,
                               unique_ptr<RandomAccessFile>&& file,
                               uint64_t file_size,
                               unique_ptr<TableReader>* table_reader,
@@ -122,9 +125,9 @@ Status PlainTableReader::Open(const Options& options,
     return s;
   }
 
-  std::unique_ptr<PlainTableReader> new_reader(
-      new PlainTableReader(soptions, file_size, bloom_bits_per_key,
-                           hash_table_ratio, table_properties));
+  std::unique_ptr<PlainTableReader> new_reader(new PlainTableReader(
+      soptions, internal_comparator, file_size, bloom_bits_per_key,
+      hash_table_ratio, table_properties));
   new_reader->file_ = std::move(file);
   new_reader->options_ = options;
 
@@ -215,10 +218,10 @@ int PlainTableReader::PopulateIndexRecordList(IndexRecordList* record_list) {
   int num_prefixes = 0;
   while (pos < data_end_offset_) {
     uint32_t key_offset = pos;
-    Slice key_slice;
+    ParsedInternalKey key;
     Slice value_slice;
-    status_ = Next(pos, &key_slice, &value_slice, pos);
-    Slice key_prefix_slice = GetPrefix(key_slice);
+    status_ = Next(pos, &key, &value_slice, pos);
+    Slice key_prefix_slice = GetPrefix(key);
 
     if (is_first_record || prev_key_prefix_slice != key_prefix_slice) {
       ++num_prefixes;
@@ -413,7 +416,11 @@ Status PlainTableReader::GetOffset(const Slice& target, const Slice& prefix,
                                                               index_ptr + 4,
                                                               &upper_bound);
   uint32_t high = upper_bound;
-  Slice mid_key;
+  ParsedInternalKey mid_key;
+  ParsedInternalKey parsed_target;
+  if (!ParseInternalKey(target, &parsed_target)) {
+    return Status::Corruption(Slice());
+  }
 
   // The key is between [low, high). Do a binary search between it.
   while (high - low > 1) {
@@ -424,8 +431,8 @@ Status PlainTableReader::GetOffset(const Slice& target, const Slice& prefix,
     if (!s.ok()) {
       return s;
     }
-    int cmp_result = options_.comparator->Compare(target, mid_key);
-    if (cmp_result > 0) {
+    int cmp_result = internal_comparator_.Compare(mid_key, parsed_target);
+    if (cmp_result < 0) {
       low = mid;
     } else {
       if (cmp_result == 0) {
@@ -442,7 +449,7 @@ Status PlainTableReader::GetOffset(const Slice& target, const Slice& prefix,
   // Both of the key at the position low or low+1 could share the same
   // prefix as target. We need to rule out one of them to avoid to go
   // to the wrong prefix.
-  Slice low_key;
+  ParsedInternalKey low_key;
   size_t tmp;
   uint32_t low_key_offset = base_ptr[low];
   Status s = ReadKey(file_data_.data() + low_key_offset, &low_key, tmp);
@@ -465,31 +472,53 @@ bool PlainTableReader::MayHavePrefix(uint32_t hash) {
   return bloom_ == nullptr || bloom_->MayContainHash(hash);
 }
 
-Status PlainTableReader::ReadKey(const char* row_ptr, Slice* key,
+Slice PlainTableReader::GetPrefix(const ParsedInternalKey& target) {
+  return options_.prefix_extractor->Transform(target.user_key);
+}
+
+Status PlainTableReader::ReadKey(const char* row_ptr, ParsedInternalKey* key,
                                  size_t& bytes_read) {
   const char* key_ptr = nullptr;
   bytes_read = 0;
-  size_t internal_key_size = 0;
+  size_t user_key_size = 0;
   if (IsFixedLength()) {
-    internal_key_size = GetFixedInternalKeyLength();
+    user_key_size = user_key_len_;
     key_ptr = row_ptr;
   } else {
-    uint32_t key_size = 0;
+    uint32_t tmp_size = 0;
     key_ptr = GetVarint32Ptr(row_ptr, file_data_.data() + data_end_offset_,
-                             &key_size);
-    internal_key_size = (size_t)key_size;
+                             &tmp_size);
+    if (key_ptr == nullptr) {
+      return Status::Corruption("Unable to read the next key");
+    }
+    user_key_size = (size_t)tmp_size;
     bytes_read = key_ptr - row_ptr;
   }
-  if (row_ptr + internal_key_size >= file_data_.data() + data_end_offset_) {
+  if (key_ptr + user_key_size + 1 >= file_data_.data() + data_end_offset_) {
     return Status::Corruption("Unable to read the next key");
   }
-  *key = Slice(key_ptr, internal_key_size);
-  bytes_read += internal_key_size;
+
+  if (*(key_ptr + user_key_size) == PlainTableFactory::kValueTypeSeqId0) {
+    // Special encoding for the row with seqID=0
+    key->user_key = Slice(key_ptr, user_key_size);
+    key->sequence = 0;
+    key->type = kTypeValue;
+    bytes_read += user_key_size + 1;
+  } else {
+    if (row_ptr + user_key_size + 8 >= file_data_.data() + data_end_offset_) {
+      return Status::Corruption("Unable to read the next key");
+    }
+    if (!ParseInternalKey(Slice(key_ptr, user_key_size + 8), key)) {
+      return Status::Corruption(Slice());
+    }
+    bytes_read += user_key_size + 8;
+  }
+
   return Status::OK();
 }
 
-Status PlainTableReader::Next(uint32_t offset, Slice* key, Slice* value,
-                              uint32_t& next_offset) {
+Status PlainTableReader::Next(uint32_t offset, ParsedInternalKey* key,
+                              Slice* value, uint32_t& next_offset) {
   if (offset == data_end_offset_) {
     next_offset = data_end_offset_;
     return Status::OK();
@@ -518,10 +547,11 @@ Status PlainTableReader::Next(uint32_t offset, Slice* key, Slice* value,
   return Status::OK();
 }
 
-Status PlainTableReader::Get(
-    const ReadOptions& ro, const Slice& target, void* arg,
-    bool (*saver)(void*, const Slice&, const Slice&, bool),
-    void (*mark_key_may_exist)(void*)) {
+Status PlainTableReader::Get(const ReadOptions& ro, const Slice& target,
+                             void* arg,
+                             bool (*saver)(void*, const ParsedInternalKey&,
+                                           const Slice&, bool),
+                             void (*mark_key_may_exist)(void*)) {
   // Check bloom filter first.
   Slice prefix_slice = GetPrefix(target);
   uint32_t prefix_hash = GetSliceHash(prefix_slice);
@@ -534,7 +564,12 @@ Status PlainTableReader::Get(
   if (!s.ok()) {
     return s;
   }
-  Slice found_key;
+  ParsedInternalKey found_key;
+  ParsedInternalKey parsed_target;
+  if (!ParseInternalKey(target, &parsed_target)) {
+    return Status::Corruption(Slice());
+  }
+
   Slice found_value;
   while (offset < data_end_offset_) {
     Status s = Next(offset, &found_key, &found_value, offset);
@@ -549,9 +584,10 @@ Status PlainTableReader::Get(
       }
       prefix_match = true;
     }
-    if (options_.comparator->Compare(found_key, target) >= 0
-        && !(*saver)(arg, found_key, found_value, true)) {
-      break;
+    if (internal_comparator_.Compare(found_key, parsed_target) >= 0) {
+      if (!(*saver)(arg, found_key, found_value, true)) {
+        break;
+      }
     }
   }
   return Status::OK();
@@ -612,7 +648,7 @@ void PlainTableIterator::Seek(const Slice& target) {
         }
         prefix_match = true;
       }
-      if (table_->options_.comparator->Compare(key(), target) >= 0) {
+      if (table_->internal_comparator_.Compare(key(), target) >= 0) {
         break;
       }
     }
@@ -623,8 +659,19 @@ void PlainTableIterator::Seek(const Slice& target) {
 
 void PlainTableIterator::Next() {
   offset_ = next_offset_;
-  Slice tmp_slice;
-  status_ = table_->Next(next_offset_, &key_, &value_, next_offset_);
+  if (offset_ < table_->data_end_offset_) {
+    Slice tmp_slice;
+    ParsedInternalKey parsed_key;
+    status_ = table_->Next(next_offset_, &parsed_key, &value_, next_offset_);
+    if (status_.ok()) {
+      // Make a copy in this case. TODO optimize.
+      tmp_str_.clear();
+      AppendInternalKey(&tmp_str_, parsed_key);
+      key_ = Slice(tmp_str_);
+    } else {
+      offset_ = next_offset_ = table_->data_end_offset_;
+    }
+  }
 }
 
 void PlainTableIterator::Prev() {
@@ -632,10 +679,12 @@ void PlainTableIterator::Prev() {
 }
 
 Slice PlainTableIterator::key() const {
+  assert(Valid());
   return key_;
 }
 
 Slice PlainTableIterator::value() const {
+  assert(Valid());
   return value_;
 }
 

table/plain_table_reader.h

@@ -6,8 +6,10 @@
 #include <unordered_map>
 #include <memory>
 #include <vector>
+#include <string>
 #include <stdint.h>
 
+#include "db/dbformat.h"
 #include "rocksdb/env.h"
 #include "rocksdb/iterator.h"
 #include "rocksdb/slice_transform.h"
@@ -27,6 +29,7 @@ struct ReadOptions;
 class TableCache;
 class TableReader;
 class DynamicBloom;
+class InternalKeyComparator;
 
 using std::unique_ptr;
 using std::unordered_map;
@@ -43,6 +46,7 @@ extern const uint32_t kPlainTableVariableLength;
 class PlainTableReader: public TableReader {
  public:
   static Status Open(const Options& options, const EnvOptions& soptions,
+                     const InternalKeyComparator& internal_comparator,
                      unique_ptr<RandomAccessFile>&& file, uint64_t file_size,
                      unique_ptr<TableReader>* table,
                      const int bloom_bits_per_key, double hash_table_ratio);
@@ -51,10 +55,10 @@ class PlainTableReader: public TableReader {
 
   Iterator* NewIterator(const ReadOptions&);
 
-  Status Get(
-      const ReadOptions&, const Slice& key, void* arg,
-      bool (*handle_result)(void* arg, const Slice& k, const Slice& v, bool),
-      void (*mark_key_may_exist)(void*) = nullptr);
+  Status Get(const ReadOptions&, const Slice& key, void* arg,
+             bool (*result_handler)(void* arg, const ParsedInternalKey& k,
+                                    const Slice& v, bool),
+             void (*mark_key_may_exist)(void*) = nullptr);
 
   uint64_t ApproximateOffsetOf(const Slice& key);
 
@@ -62,8 +66,10 @@ class PlainTableReader: public TableReader {
 
   const TableProperties& GetTableProperties() { return table_properties_; }
 
-  PlainTableReader(const EnvOptions& storage_options, uint64_t file_size,
-                   int bloom_bits_per_key, double hash_table_ratio,
+  PlainTableReader(const EnvOptions& storage_options,
+                   const InternalKeyComparator& internal_comparator,
+                   uint64_t file_size, int bloom_num_bits,
+                   double hash_table_ratio,
                    const TableProperties& table_properties);
   ~PlainTableReader();
 
@@ -77,6 +83,7 @@ class PlainTableReader: public TableReader {
 
   Options options_;
   const EnvOptions& soptions_;
+  const InternalKeyComparator internal_comparator_;
   Status status_;
   unique_ptr<RandomAccessFile> file_;
 
@@ -184,11 +191,13 @@ class PlainTableReader: public TableReader {
   // too.
   bool MayHavePrefix(uint32_t hash);
 
-  Status ReadKey(const char* row_ptr, Slice* key, size_t& bytes_read);
+  Status ReadKey(const char* row_ptr, ParsedInternalKey* key,
+                 size_t& bytes_read);
   // Read the key and value at offset to key and value.
   // tmp_slice is a tmp slice.
   // return next_offset as the offset for the next key.
-  Status Next(uint32_t offset, Slice* key, Slice* value, uint32_t& next_offset);
+  Status Next(uint32_t offset, ParsedInternalKey* key, Slice* value,
+              uint32_t& next_offset);
   // Get file offset for key target.
   // return value prefix_matched is set to true if the offset is confirmed
   // for a key with the same prefix as target.
@@ -202,6 +211,8 @@ class PlainTableReader: public TableReader {
         Slice(target.data(), target.size() - 8));
   }
 
+  Slice GetPrefix(const ParsedInternalKey& target);
+
   // No copying allowed
   explicit PlainTableReader(const TableReader&) = delete;
   void operator=(const TableReader&) = delete;

table/table_factory.h

@@ -53,6 +53,7 @@ class TableFactory {
   // table_reader is the output table reader
   virtual Status NewTableReader(
       const Options& options, const EnvOptions& soptions,
+      const InternalKeyComparator& internal_comparator,
       unique_ptr<RandomAccessFile>&& file, uint64_t file_size,
       unique_ptr<TableReader>* table_reader) const = 0;
 
@@ -75,8 +76,8 @@ class TableFactory {
   // keep the file open and close the file after closing the table builder.
   // compression_type is the compression type to use in this table.
   virtual TableBuilder* NewTableBuilder(
-      const Options& options, WritableFile* file,
-      CompressionType compression_type) const = 0;
+      const Options& options, const InternalKeyComparator& internal_comparator,
+      WritableFile* file, CompressionType compression_type) const = 0;
 };
 
 }  // namespace rocksdb

table/table_reader.h

@@ -12,6 +12,7 @@
 namespace rocksdb {
 
 class Iterator;
+class ParsedInternalKey;
 class Slice;
 struct ReadOptions;
 struct TableProperties;
@@ -62,7 +63,7 @@ class TableReader {
   // key is the key to search for
   virtual Status Get(
       const ReadOptions& readOptions, const Slice& key, void* handle_context,
-      bool (*result_handler)(void* handle_context, const Slice& k,
+      bool (*result_handler)(void* arg, const ParsedInternalKey& k,
                              const Slice& v, bool didIO),
       void (*mark_key_may_exist_handler)(void* handle_context) = nullptr) = 0;
 };

table/table_reader_bench.cc

@@ -34,8 +34,8 @@ static std::string MakeKey(int i, int j, bool through_db) {
   return key.Encode().ToString();
 }
 
-static bool DummySaveValue(void* arg, const Slice& ikey, const Slice& v,
-                           bool didIO) {
+static bool DummySaveValue(void* arg, const ParsedInternalKey& ikey,
+                           const Slice& v, bool didIO) {
   return false;
 }
 
@@ -237,6 +237,8 @@ int main(int argc, char** argv) {
   rocksdb::EnvOptions env_options;
   options.create_if_missing = true;
   options.compression = rocksdb::CompressionType::kNoCompression;
+  options.internal_comparator =
+      new rocksdb::InternalKeyComparator(options.comparator);
 
   if (FLAGS_plain_table) {
     options.allow_mmap_reads = true;

table/table_test.cc

@@ -183,8 +183,9 @@ class Constructor {
   // been added so far.  Returns the keys in sorted order in "*keys"
   // and stores the key/value pairs in "*kvmap"
   void Finish(const Options& options,
-              std::vector<std::string>* keys,
-              KVMap* kvmap) {
+              const InternalKeyComparator& internal_comparator,
+              std::vector<std::string>* keys, KVMap* kvmap) {
+    last_internal_key_ = &internal_comparator;
     *kvmap = data_;
     keys->clear();
     for (KVMap::const_iterator it = data_.begin();
@@ -193,12 +194,14 @@ class Constructor {
       keys->push_back(it->first);
     }
     data_.clear();
-    Status s = FinishImpl(options, *kvmap);
+    Status s = FinishImpl(options, internal_comparator, *kvmap);
     ASSERT_TRUE(s.ok()) << s.ToString();
   }
 
   // Construct the data structure from the data in "data"
-  virtual Status FinishImpl(const Options& options, const KVMap& data) = 0;
+  virtual Status FinishImpl(const Options& options,
+                            const InternalKeyComparator& internal_comparator,
+                            const KVMap& data) = 0;
 
   virtual Iterator* NewIterator() const = 0;
 
@@ -206,6 +209,9 @@ class Constructor {
 
   virtual DB* db() const { return nullptr; }  // Overridden in DBConstructor
 
+ protected:
+  const InternalKeyComparator* last_internal_key_;
+
  private:
   KVMap data_;
 };
@@ -219,10 +225,12 @@ class BlockConstructor: public Constructor {
   ~BlockConstructor() {
     delete block_;
   }
-  virtual Status FinishImpl(const Options& options, const KVMap& data) {
+  virtual Status FinishImpl(const Options& options,
+                            const InternalKeyComparator& internal_comparator,
+                            const KVMap& data) {
     delete block_;
     block_ = nullptr;
-    BlockBuilder builder(options);
+    BlockBuilder builder(options, &internal_comparator);
 
     for (KVMap::const_iterator it = data.begin();
          it != data.end();
@@ -298,12 +306,14 @@ class TableConstructor: public Constructor {
       : Constructor(cmp), convert_to_internal_key_(convert_to_internal_key) {}
   ~TableConstructor() { Reset(); }
 
-  virtual Status FinishImpl(const Options& options, const KVMap& data) {
+  virtual Status FinishImpl(const Options& options,
+                            const InternalKeyComparator& internal_comparator,
+                            const KVMap& data) {
     Reset();
     sink_.reset(new StringSink());
     unique_ptr<TableBuilder> builder;
-    builder.reset(options.table_factory->NewTableBuilder(options, sink_.get(),
-                                                         options.compression));
+    builder.reset(options.table_factory->NewTableBuilder(
+        options, internal_comparator, sink_.get(), options.compression));
 
     for (KVMap::const_iterator it = data.begin();
          it != data.end();
@@ -328,8 +338,8 @@ class TableConstructor: public Constructor {
     source_.reset(new StringSource(sink_->contents(), uniq_id_,
                                    options.allow_mmap_reads));
     return options.table_factory->NewTableReader(
-        options, soptions, std::move(source_), sink_->contents().size(),
-        &table_reader_);
+        options, soptions, internal_comparator, std::move(source_),
+        sink_->contents().size(), &table_reader_);
   }
 
   virtual Iterator* NewIterator() const {
@@ -350,8 +360,8 @@ class TableConstructor: public Constructor {
         new StringSource(sink_->contents(), uniq_id_,
                          options.allow_mmap_reads));
     return options.table_factory->NewTableReader(
-        options, soptions, std::move(source_), sink_->contents().size(),
-        &table_reader_);
+        options, soptions, *last_internal_key_, std::move(source_),
+        sink_->contents().size(), &table_reader_);
   }
 
   virtual TableReader* table_reader() {
@@ -393,7 +403,9 @@ class MemTableConstructor: public Constructor {
   ~MemTableConstructor() {
     delete memtable_->Unref();
   }
-  virtual Status FinishImpl(const Options& options, const KVMap& data) {
+  virtual Status FinishImpl(const Options& options,
+                            const InternalKeyComparator& internal_comparator,
+                            const KVMap& data) {
     delete memtable_->Unref();
     Options memtable_options;
     memtable_options.memtable_factory = table_factory_;
@@ -429,7 +441,9 @@ class DBConstructor: public Constructor {
   ~DBConstructor() {
     delete db_;
   }
-  virtual Status FinishImpl(const Options& options, const KVMap& data) {
+  virtual Status FinishImpl(const Options& options,
+                            const InternalKeyComparator& internal_comparator,
+                            const KVMap& data) {
     delete db_;
     db_ = nullptr;
     NewDB();
@@ -619,7 +633,10 @@ class Harness {
     if (args.reverse_compare) {
       options_.comparator = &reverse_key_comparator;
     }
-    internal_comparator_.reset(new InternalKeyComparator(options_.comparator));
+
+    internal_comparator_.reset(
+        new test::PlainInternalKeyComparator(options_.comparator));
+
     support_prev_ = true;
     only_support_prefix_seek_ = false;
     BlockBasedTableOptions table_options;
@@ -638,7 +655,8 @@ class Harness {
         options_.allow_mmap_reads = true;
         options_.table_factory.reset(new PlainTableFactory());
         constructor_ = new TableConstructor(options_.comparator, true);
-        options_.comparator = internal_comparator_.get();
+        internal_comparator_.reset(
+            new InternalKeyComparator(options_.comparator));
         break;
       case PLAIN_TABLE_FULL_STR_PREFIX:
         support_prev_ = false;
@@ -647,7 +665,8 @@ class Harness {
         options_.allow_mmap_reads = true;
         options_.table_factory.reset(new PlainTableFactory());
         constructor_ = new TableConstructor(options_.comparator, true);
-        options_.comparator = internal_comparator_.get();
+        internal_comparator_.reset(
+            new InternalKeyComparator(options_.comparator));
         break;
       case BLOCK_TEST:
         constructor_ = new BlockConstructor(options_.comparator);
@@ -672,7 +691,7 @@ class Harness {
   void Test(Random* rnd) {
     std::vector<std::string> keys;
     KVMap data;
-    constructor_->Finish(options_, &keys, &data);
+    constructor_->Finish(options_, *internal_comparator_, &keys, &data);
 
     TestForwardScan(keys, data);
     if (support_prev_) {
@@ -844,7 +863,7 @@ class Harness {
   Constructor* constructor_;
   bool support_prev_;
   bool only_support_prefix_seek_;
-  shared_ptr<Comparator> internal_comparator_;
+  shared_ptr<InternalKeyComparator> internal_comparator_;
   static std::unique_ptr<const SliceTransform> noop_transform;
   static std::unique_ptr<const SliceTransform> prefix_transform;
 };
@@ -866,9 +885,24 @@ static bool Between(uint64_t val, uint64_t low, uint64_t high) {
 }
 
 // Tests against all kinds of tables
-class GeneralTableTest {};
-class BlockBasedTableTest {};
-class PlainTableTest {};
+class TableTest {
+ public:
+  const InternalKeyComparator& GetPlainInternalComparator(
+      const Comparator* comp) {
+    if (!plain_internal_comparator) {
+      plain_internal_comparator.reset(
+          new test::PlainInternalKeyComparator(comp));
+    }
+    return *plain_internal_comparator;
+  }
+
+ private:
+  std::unique_ptr<InternalKeyComparator> plain_internal_comparator;
+};
+
+class GeneralTableTest : public TableTest {};
+class BlockBasedTableTest : public TableTest {};
+class PlainTableTest : public TableTest {};
 
 // This test include all the basic checks except those for index size and block
 // size, which will be conducted in separated unit tests.
@@ -891,7 +925,8 @@ TEST(BlockBasedTableTest, BasicBlockBasedTableProperties) {
   options.compression = kNoCompression;
   options.block_restart_interval = 1;
 
-  c.Finish(options, &keys, &kvmap);
+  c.Finish(options, GetPlainInternalComparator(options.comparator), &keys,
+           &kvmap);
 
   auto& props = c.table_reader()->GetTableProperties();
   ASSERT_EQ(kvmap.size(), props.num_entries);
@@ -905,7 +940,7 @@ TEST(BlockBasedTableTest, BasicBlockBasedTableProperties) {
   ASSERT_EQ("", props.filter_policy_name);  // no filter policy is used
 
   // Verify data size.
-  BlockBuilder block_builder(options);
+  BlockBuilder block_builder(options, options.comparator);
   for (const auto& item : kvmap) {
     block_builder.Add(item.first, item.second);
   }
@@ -927,7 +962,8 @@ TEST(BlockBasedTableTest, FilterPolicyNameProperties) {
   );
   options.filter_policy = filter_policy.get();
 
-  c.Finish(options, &keys, &kvmap);
+  c.Finish(options, GetPlainInternalComparator(options.comparator), &keys,
+           &kvmap);
   auto& props = c.table_reader()->GetTableProperties();
   ASSERT_EQ("rocksdb.BuiltinBloomFilter", props.filter_policy_name);
 }
@@ -968,7 +1004,8 @@ TEST(BlockBasedTableTest, IndexSizeStat) {
     options.compression = kNoCompression;
     options.block_restart_interval = 1;
 
-    c.Finish(options, &ks, &kvmap);
+    c.Finish(options, GetPlainInternalComparator(options.comparator), &ks,
+             &kvmap);
     auto index_size =
       c.table_reader()->GetTableProperties().index_size;
     ASSERT_GT(index_size, last_index_size);
@@ -992,7 +1029,8 @@ TEST(BlockBasedTableTest, NumBlockStat) {
 
   std::vector<std::string> ks;
   KVMap kvmap;
-  c.Finish(options, &ks, &kvmap);
+  c.Finish(options, GetPlainInternalComparator(options.comparator), &ks,
+           &kvmap);
   ASSERT_EQ(
       kvmap.size(),
       c.table_reader()->GetTableProperties().num_data_blocks
@@ -1055,7 +1093,8 @@ TEST(BlockBasedTableTest, BlockCacheTest) {
 
   TableConstructor c(BytewiseComparator());
   c.Add("key", "value");
-  c.Finish(options, &keys, &kvmap);
+  c.Finish(options, GetPlainInternalComparator(options.comparator), &keys,
+           &kvmap);
 
   // -- PART 1: Open with regular block cache.
   // Since block_cache is disabled, no cache activities will be involved.
@@ -1179,6 +1218,8 @@ TEST(BlockBasedTableTest, BlockCacheLeak) {
   // unique ID from the file.
 
   Options opt;
+  unique_ptr<InternalKeyComparator> ikc;
+  ikc.reset(new test::PlainInternalKeyComparator(opt.comparator));
   opt.block_size = 1024;
   opt.compression = kNoCompression;
   opt.block_cache =
@@ -1195,7 +1236,7 @@ TEST(BlockBasedTableTest, BlockCacheLeak) {
   c.Add("k07", std::string(100000, 'x'));
   std::vector<std::string> keys;
   KVMap kvmap;
-  c.Finish(opt, &keys, &kvmap);
+  c.Finish(opt, *ikc, &keys, &kvmap);
 
   unique_ptr<Iterator> iter(c.NewIterator());
   iter->SeekToFirst();
@@ -1217,11 +1258,14 @@ extern const uint64_t kPlainTableMagicNumber;
 TEST(PlainTableTest, BasicPlainTableProperties) {
   PlainTableFactory factory(8, 8, 0);
   StringSink sink;
+  Options options;
+  InternalKeyComparator ikc(options.comparator);
   std::unique_ptr<TableBuilder> builder(
-      factory.NewTableBuilder(Options(), &sink, kNoCompression));
+      factory.NewTableBuilder(options, ikc, &sink, kNoCompression));
 
   for (char c = 'a'; c <= 'z'; ++c) {
-    std::string key(16, c);
+    std::string key(8, c);
+    key.append("\1       ");  // PlainTable expects internal key structure
     std::string value(28, c + 42);
     builder->Add(key, value);
   }
@@ -1255,9 +1299,10 @@ TEST(GeneralTableTest, ApproximateOffsetOfPlain) {
   std::vector<std::string> keys;
   KVMap kvmap;
   Options options;
+  test::PlainInternalKeyComparator internal_comparator(options.comparator);
   options.block_size = 1024;
   options.compression = kNoCompression;
-  c.Finish(options, &keys, &kvmap);
+  c.Finish(options, internal_comparator, &keys, &kvmap);
 
   ASSERT_TRUE(Between(c.ApproximateOffsetOf("abc"),       0,      0));
   ASSERT_TRUE(Between(c.ApproximateOffsetOf("k01"),       0,      0));
@@ -1284,9 +1329,10 @@ static void DoCompressionTest(CompressionType comp) {
   std::vector<std::string> keys;
   KVMap kvmap;
   Options options;
+  test::PlainInternalKeyComparator ikc(options.comparator);
   options.block_size = 1024;
   options.compression = comp;
-  c.Finish(options, &keys, &kvmap);
+  c.Finish(options, ikc, &keys, &kvmap);
 
   ASSERT_TRUE(Between(c.ApproximateOffsetOf("abc"),       0,      0));
   ASSERT_TRUE(Between(c.ApproximateOffsetOf("k01"),       0,      0));

table/two_level_iterator.cc

@@ -20,18 +20,17 @@ namespace rocksdb {
 namespace {
 
 typedef Iterator* (*BlockFunction)(void*, const ReadOptions&,
-                                   const EnvOptions& soptions, const Slice&,
-                                   bool for_compaction);
+                                   const EnvOptions& soptions,
+                                   const InternalKeyComparator& icomparator,
+                                   const Slice&, bool for_compaction);
 
 class TwoLevelIterator: public Iterator {
  public:
-  TwoLevelIterator(
-    Iterator* index_iter,
-    BlockFunction block_function,
-    void* arg,
-    const ReadOptions& options,
-    const EnvOptions& soptions,
-    bool for_compaction);
+  TwoLevelIterator(Iterator* index_iter, BlockFunction block_function,
+                   void* arg, const ReadOptions& options,
+                   const EnvOptions& soptions,
+                   const InternalKeyComparator& internal_comparator,
+                   bool for_compaction);
 
   virtual ~TwoLevelIterator();
 
@@ -76,6 +75,7 @@ class TwoLevelIterator: public Iterator {
   void* arg_;
   const ReadOptions options_;
   const EnvOptions& soptions_;
+  const InternalKeyComparator& internal_comparator_;
   Status status_;
   IteratorWrapper index_iter_;
   IteratorWrapper data_iter_; // May be nullptr
@@ -86,20 +86,17 @@ class TwoLevelIterator: public Iterator {
 };
 
 TwoLevelIterator::TwoLevelIterator(
-    Iterator* index_iter,
-    BlockFunction block_function,
-    void* arg,
-    const ReadOptions& options,
-    const EnvOptions& soptions,
-    bool for_compaction)
+    Iterator* index_iter, BlockFunction block_function, void* arg,
+    const ReadOptions& options, const EnvOptions& soptions,
+    const InternalKeyComparator& internal_comparator, bool for_compaction)
     : block_function_(block_function),
       arg_(arg),
       options_(options),
       soptions_(soptions),
+      internal_comparator_(internal_comparator),
       index_iter_(index_iter),
       data_iter_(nullptr),
-      for_compaction_(for_compaction) {
-}
+      for_compaction_(for_compaction) {}
 
 TwoLevelIterator::~TwoLevelIterator() {
 }
@@ -181,8 +178,9 @@ void TwoLevelIterator::InitDataBlock() {
       // data_iter_ is already constructed with this iterator, so
       // no need to change anything
     } else {
-      Iterator* iter = (*block_function_)(arg_, options_, soptions_, handle,
-                                          for_compaction_);
+      Iterator* iter =
+          (*block_function_)(arg_, options_, soptions_, internal_comparator_,
+                             handle, for_compaction_);
       data_block_handle_.assign(handle.data(), handle.size());
       SetDataIterator(iter);
     }
@@ -191,15 +189,14 @@ void TwoLevelIterator::InitDataBlock() {
 
 }  // namespace
 
-Iterator* NewTwoLevelIterator(
-    Iterator* index_iter,
-    BlockFunction block_function,
-    void* arg,
-    const ReadOptions& options,
-    const EnvOptions& soptions,
-    bool for_compaction) {
-  return new TwoLevelIterator(index_iter, block_function, arg,
-                              options, soptions, for_compaction);
+Iterator* NewTwoLevelIterator(Iterator* index_iter,
+                              BlockFunction block_function, void* arg,
+                              const ReadOptions& options,
+                              const EnvOptions& soptions,
+                              const InternalKeyComparator& internal_comparator,
+                              bool for_compaction) {
+  return new TwoLevelIterator(index_iter, block_function, arg, options,
+                              soptions, internal_comparator, for_compaction);
 }
 
 }  // namespace rocksdb

table/two_level_iterator.h

@@ -14,6 +14,7 @@
 namespace rocksdb {
 
 struct ReadOptions;
+class InternalKeyComparator;
 
 // Return a new two level iterator.  A two-level iterator contains an
 // index iterator whose values point to a sequence of blocks where
@@ -27,14 +28,11 @@ struct ReadOptions;
 extern Iterator* NewTwoLevelIterator(
     Iterator* index_iter,
     Iterator* (*block_function)(
-        void* arg,
-        const ReadOptions& options,
-        const EnvOptions& soptions,
-        const Slice& index_value,
-        bool for_compaction),
-    void* arg,
-    const ReadOptions& options,
-    const EnvOptions& soptions,
+        void* arg, const ReadOptions& options, const EnvOptions& soptions,
+        const InternalKeyComparator& internal_comparator,
+        const Slice& index_value, bool for_compaction),
+    void* arg, const ReadOptions& options, const EnvOptions& soptions,
+    const InternalKeyComparator& internal_comparator,
     bool for_compaction = false);
 
 }  // namespace rocksdb

tools/sst_dump.cc

@@ -71,7 +71,6 @@ SstFileReader::SstFileReader(const std::string& file_path,
 }
 
 Status SstFileReader::NewTableReader(const std::string& file_path) {
-  table_options_.comparator = &internal_comparator_;
   Status s = table_options_.env->NewRandomAccessFile(file_path, &file_,
                                                     soptions_);
   if (!s.ok()) {
@@ -81,7 +80,8 @@ Status SstFileReader::NewTableReader(const std::string& file_path) {
   table_options_.env->GetFileSize(file_path, &file_size);
   unique_ptr<TableFactory> table_factory;
   s = table_options_.table_factory->NewTableReader(
-      table_options_, soptions_, std::move(file_), file_size, &table_reader_);
+      table_options_, soptions_, internal_comparator_, std::move(file_),
+      file_size, &table_reader_);
   return s;
 }
 

util/testutil.h

@@ -8,6 +8,8 @@
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 
 #pragma once
+#include <string>
+#include "db/dbformat.h"
 #include "rocksdb/env.h"
 #include "rocksdb/slice.h"
 #include "util/random.h"
@@ -51,5 +53,28 @@ class ErrorEnv : public EnvWrapper {
   }
 };
 
+// An internal comparator that just forward comparing results from the
+// user comparator in it. Can be used to test entities that have no dependency
+// on internal key structure but consumes InternalKeyComparator, like
+// BlockBasedTable.
+class PlainInternalKeyComparator : public InternalKeyComparator {
+ public:
+  explicit PlainInternalKeyComparator(const Comparator* c)
+      : InternalKeyComparator(c) {}
+
+  virtual ~PlainInternalKeyComparator() {}
+
+  virtual int Compare(const Slice& a, const Slice& b) const override {
+    return user_comparator()->Compare(a, b);
+  }
+  virtual void FindShortestSeparator(std::string* start,
+                                     const Slice& limit) const override {
+    user_comparator()->FindShortestSeparator(start, limit);
+  }
+  virtual void FindShortSuccessor(std::string* key) const override {
+    user_comparator()->FindShortSuccessor(key);
+  }
+};
+
 }  // namespace test
 }  // namespace rocksdb