Make MemTableRepFactory into a Customizable class (#8419)

Summary:
This PR does the following:
-> Makes the MemTableRepFactory into a Customizable class and creatable/configurable via CreateFromString
-> Makes the existing implementations compatible with configurations
-> Moves the "SpecialRepFactory" test class into testutil, accessible via the ObjectRegistry or a NewSpecial API

New tests were added to validate the functionality and all existing tests pass.  db_bench and memtablerep_bench were hand-tested to verify the functionality in those tools.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8419

Reviewed By: zhichao-cao

Differential Revision: D29558961

Pulled By: mrambacher

fbshipit-source-id: 81b7229636e4e649a0c914e73ac7b0f8454c931c

db/column_family.cc

@@ -29,7 +29,6 @@
 #include "db/version_set.h"
 #include "db/write_controller.h"
 #include "file/sst_file_manager_impl.h"
-#include "memtable/hash_skiplist_rep.h"
 #include "monitoring/thread_status_util.h"
 #include "options/options_helper.h"
 #include "port/port.h"

db/column_family_test.cc

@@ -2975,7 +2975,8 @@ TEST_P(ColumnFamilyTest, FlushCloseWALFiles) {
   SpecialEnv env(Env::Default());
   db_options_.env = &env;
   db_options_.max_background_flushes = 1;
-  column_family_options_.memtable_factory.reset(new SpecialSkipListFactory(2));
+  column_family_options_.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(2));
   Open();
   CreateColumnFamilies({"one"});
   ASSERT_OK(Put(1, "fodor", "mirko"));
@@ -3020,7 +3021,8 @@ TEST_P(ColumnFamilyTest, IteratorCloseWALFile1) {
   SpecialEnv env(Env::Default());
   db_options_.env = &env;
   db_options_.max_background_flushes = 1;
-  column_family_options_.memtable_factory.reset(new SpecialSkipListFactory(2));
+  column_family_options_.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(2));
   Open();
   CreateColumnFamilies({"one"});
   ASSERT_OK(Put(1, "fodor", "mirko"));
@@ -3071,7 +3073,8 @@ TEST_P(ColumnFamilyTest, IteratorCloseWALFile2) {
   env.SetBackgroundThreads(2, Env::HIGH);
   db_options_.env = &env;
   db_options_.max_background_flushes = 1;
-  column_family_options_.memtable_factory.reset(new SpecialSkipListFactory(2));
+  column_family_options_.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(2));
   Open();
   CreateColumnFamilies({"one"});
   ASSERT_OK(Put(1, "fodor", "mirko"));
@@ -3129,7 +3132,8 @@ TEST_P(ColumnFamilyTest, ForwardIteratorCloseWALFile) {
   env.SetBackgroundThreads(2, Env::HIGH);
   db_options_.env = &env;
   db_options_.max_background_flushes = 1;
-  column_family_options_.memtable_factory.reset(new SpecialSkipListFactory(3));
+  column_family_options_.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(3));
   column_family_options_.level0_file_num_compaction_trigger = 2;
   Open();
   CreateColumnFamilies({"one"});

db/compaction/compaction_job_stats_test.cc

@@ -24,7 +24,6 @@
 #include "db/write_batch_internal.h"
 #include "env/mock_env.h"
 #include "file/filename.h"
-#include "memtable/hash_linklist_rep.h"
 #include "monitoring/statistics.h"
 #include "monitoring/thread_status_util.h"
 #include "port/stack_trace.h"

db/db_bloom_filter_test.cc

@@ -15,6 +15,7 @@
 #include "port/stack_trace.h"
 #include "rocksdb/perf_context.h"
 #include "table/block_based/filter_policy_internal.h"
+#include "test_util/testutil.h"
 #include "util/string_util.h"
 
 namespace ROCKSDB_NAMESPACE {
@@ -2171,7 +2172,8 @@ TEST_F(DBBloomFilterTest, SeekForPrevWithPartitionedFilters) {
   Options options = CurrentOptions();
   constexpr size_t kNumKeys = 10000;
   static_assert(kNumKeys <= 10000, "kNumKeys have to be <= 10000");
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeys + 10));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeys + 10));
   options.create_if_missing = true;
   constexpr size_t kPrefixLength = 4;
   options.prefix_extractor.reset(NewFixedPrefixTransform(kPrefixLength));

db/db_compaction_test.cc

@@ -19,6 +19,7 @@
 #include "rocksdb/sst_file_writer.h"
 #include "rocksdb/utilities/convenience.h"
 #include "test_util/sync_point.h"
+#include "test_util/testutil.h"
 #include "util/concurrent_task_limiter_impl.h"
 #include "util/random.h"
 #include "utilities/fault_injection_env.h"
@@ -805,7 +806,8 @@ TEST_P(DBCompactionTestWithParam, CompactionTrigger) {
   options.num_levels = 3;
   options.level0_file_num_compaction_trigger = 3;
   options.max_subcompactions = max_subcompactions_;
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeysPerFile));
   CreateAndReopenWithCF({"pikachu"}, options);
 
   Random rnd(301);
@@ -852,7 +854,8 @@ TEST_F(DBCompactionTest, BGCompactionsAllowed) {
   options.level0_slowdown_writes_trigger = 20;
   options.soft_pending_compaction_bytes_limit = 1 << 30;  // Infinitely large
   options.max_background_compactions = 3;
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeysPerFile));
 
   // Block all threads in thread pool.
   const size_t kTotalTasks = 4;
@@ -2094,7 +2097,7 @@ TEST_P(DBCompactionTestWithParam, LevelCompactionThirdPath) {
   options.db_paths.emplace_back(dbname_ + "_2", 4 * 1024 * 1024);
   options.db_paths.emplace_back(dbname_ + "_3", 1024 * 1024 * 1024);
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
+      test::NewSpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
   options.compaction_style = kCompactionStyleLevel;
   options.write_buffer_size = 110 << 10;  // 110KB
   options.arena_block_size = 4 << 10;
@@ -2203,7 +2206,7 @@ TEST_P(DBCompactionTestWithParam, LevelCompactionPathUse) {
   options.db_paths.emplace_back(dbname_ + "_2", 4 * 1024 * 1024);
   options.db_paths.emplace_back(dbname_ + "_3", 1024 * 1024 * 1024);
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
+      test::NewSpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
   options.compaction_style = kCompactionStyleLevel;
   options.write_buffer_size = 110 << 10;  // 110KB
   options.arena_block_size = 4 << 10;
@@ -2313,7 +2316,7 @@ TEST_P(DBCompactionTestWithParam, LevelCompactionCFPathUse) {
   options.db_paths.emplace_back(dbname_ + "_2", 4 * 1024 * 1024);
   options.db_paths.emplace_back(dbname_ + "_3", 1024 * 1024 * 1024);
   options.memtable_factory.reset(
-    new SpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
+      test::NewSpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
   options.compaction_style = kCompactionStyleLevel;
   options.write_buffer_size = 110 << 10;  // 110KB
   options.arena_block_size = 4 << 10;
@@ -3012,7 +3015,7 @@ TEST_P(DBCompactionTestWithParam, CompressLevelCompaction) {
   }
   Options options = CurrentOptions();
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
+      test::NewSpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
   options.compaction_style = kCompactionStyleLevel;
   options.write_buffer_size = 110 << 10;  // 110KB
   options.arena_block_size = 4 << 10;
@@ -4815,7 +4818,8 @@ TEST_F(DBCompactionTest, CompactionLimiter) {
   options.level0_slowdown_writes_trigger = 64;
   options.level0_stop_writes_trigger = 64;
   options.max_background_jobs = kMaxBackgroundThreads; // Enough threads
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeysPerFile));
   options.max_write_buffer_number = 10; // Enough memtables
   DestroyAndReopen(options);
 
@@ -5338,7 +5342,8 @@ TEST_P(DBCompactionTestWithParam, FixFileIngestionCompactionDeadlock) {
   options.level0_file_num_compaction_trigger =
       options.level0_stop_writes_trigger;
   options.max_subcompactions = max_subcompactions_;
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeysPerFile));
   DestroyAndReopen(options);
   Random rnd(301);
 
@@ -5864,7 +5869,7 @@ TEST_F(DBCompactionTest, ChangeLevelCompactRangeConflictsWithManual) {
   // `Status::Incomplete`.
   Options options = CurrentOptions();
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
+      test::NewSpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
   options.level0_file_num_compaction_trigger = 2;
   options.num_levels = 3;
   Reopen(options);
@@ -5952,7 +5957,7 @@ TEST_F(DBCompactionTest, ChangeLevelErrorPathTest) {
   // succeeds
   Options options = CurrentOptions();
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
+      test::NewSpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
   options.level0_file_num_compaction_trigger = 2;
   options.num_levels = 3;
   Reopen(options);

db/db_flush_test.cc

@@ -18,6 +18,7 @@
 #include "port/stack_trace.h"
 #include "rocksdb/utilities/transaction_db.h"
 #include "test_util/sync_point.h"
+#include "test_util/testutil.h"
 #include "util/cast_util.h"
 #include "util/mutexlock.h"
 #include "utilities/fault_injection_env.h"
@@ -139,7 +140,7 @@ TEST_F(DBFlushTest, FlushInLowPriThreadPool) {
   // scheduled in the low-pri (compaction) thread pool.
   Options options = CurrentOptions();
   options.level0_file_num_compaction_trigger = 4;
-  options.memtable_factory.reset(new SpecialSkipListFactory(1));
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(1));
   Reopen(options);
   env_->SetBackgroundThreads(0, Env::HIGH);
 
@@ -2320,7 +2321,7 @@ TEST_P(DBAtomicFlushTest, TriggerFlushAndClose) {
   options.create_if_missing = true;
   options.atomic_flush = atomic_flush;
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(kNumKeysTriggerFlush));
+      test::NewSpecialSkipListFactory(kNumKeysTriggerFlush));
   CreateAndReopenWithCF({"pikachu"}, options);
 
   for (int i = 0; i != kNumKeysTriggerFlush; ++i) {

db/db_impl/db_impl.cc

@@ -61,8 +61,6 @@
 #include "logging/auto_roll_logger.h"
 #include "logging/log_buffer.h"
 #include "logging/logging.h"
-#include "memtable/hash_linklist_rep.h"
-#include "memtable/hash_skiplist_rep.h"
 #include "monitoring/in_memory_stats_history.h"
 #include "monitoring/instrumented_mutex.h"
 #include "monitoring/iostats_context_imp.h"

db/db_io_failure_test.cc

@@ -9,6 +9,7 @@
 
 #include "db/db_test_util.h"
 #include "port/stack_trace.h"
+#include "test_util/testutil.h"
 #include "util/random.h"
 
 namespace ROCKSDB_NAMESPACE {
@@ -269,7 +270,7 @@ TEST_F(DBIOFailureTest, FlushSstRangeSyncError) {
   options.writable_file_max_buffer_size = 128 * 1024;
   options.bytes_per_sync = 128 * 1024;
   options.level0_file_num_compaction_trigger = 4;
-  options.memtable_factory.reset(new SpecialSkipListFactory(10));
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(10));
   BlockBasedTableOptions table_options;
   table_options.filter_policy.reset(NewBloomFilterPolicy(10));
   options.table_factory.reset(NewBlockBasedTableFactory(table_options));
@@ -396,7 +397,7 @@ TEST_F(DBIOFailureTest, FlushSstCloseError) {
   options.error_if_exists = false;
   options.paranoid_checks = true;
   options.level0_file_num_compaction_trigger = 4;
-  options.memtable_factory.reset(new SpecialSkipListFactory(2));
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(2));
 
   DestroyAndReopen(options);
   CreateAndReopenWithCF({"pikachu"}, options);
@@ -492,7 +493,7 @@ TEST_F(DBIOFailureTest, FlushSstSyncError) {
   options.paranoid_checks = true;
   options.use_fsync = false;
   options.level0_file_num_compaction_trigger = 4;
-  options.memtable_factory.reset(new SpecialSkipListFactory(2));
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(2));
 
   DestroyAndReopen(options);
   CreateAndReopenWithCF({"pikachu"}, options);

db/db_range_del_test.cc

@@ -118,7 +118,7 @@ TEST_F(DBRangeDelTest, CompactionOutputFilesExactlyFilled) {
   Options options = CurrentOptions();
   options.disable_auto_compactions = true;
   options.level0_file_num_compaction_trigger = kNumFiles;
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumPerFile));
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(kNumPerFile));
   options.num_levels = 2;
   options.target_file_size_base = kFileBytes;
   BlockBasedTableOptions table_options;
@@ -166,7 +166,7 @@ TEST_F(DBRangeDelTest, MaxCompactionBytesCutsOutputFiles) {
   opts.disable_auto_compactions = true;
   opts.level0_file_num_compaction_trigger = kNumFiles;
   opts.max_compaction_bytes = kNumPerFile * kBytesPerVal;
-  opts.memtable_factory.reset(new SpecialSkipListFactory(kNumPerFile));
+  opts.memtable_factory.reset(test::NewSpecialSkipListFactory(kNumPerFile));
   // Want max_compaction_bytes to trigger the end of compaction output file, not
   // target_file_size_base, so make the latter much bigger
   opts.target_file_size_base = 100 * opts.max_compaction_bytes;
@@ -319,7 +319,7 @@ TEST_F(DBRangeDelTest, CompactionRemovesCoveredKeys) {
   Options opts = CurrentOptions();
   opts.comparator = test::Uint64Comparator();
   opts.disable_auto_compactions = true;
-  opts.memtable_factory.reset(new SpecialSkipListFactory(kNumPerFile));
+  opts.memtable_factory.reset(test::NewSpecialSkipListFactory(kNumPerFile));
   opts.num_levels = 2;
   opts.statistics = CreateDBStatistics();
   DestroyAndReopen(opts);
@@ -377,7 +377,7 @@ TEST_F(DBRangeDelTest, ValidLevelSubcompactionBoundaries) {
   options.level0_file_num_compaction_trigger = kNumFiles;
   options.max_bytes_for_level_base = 2 * kFileBytes;
   options.max_subcompactions = 4;
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumPerFile));
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(kNumPerFile));
   options.num_levels = 3;
   options.target_file_size_base = kFileBytes;
   options.target_file_size_multiplier = 1;
@@ -436,7 +436,7 @@ TEST_F(DBRangeDelTest, ValidUniversalSubcompactionBoundaries) {
   options.compaction_style = kCompactionStyleUniversal;
   options.level0_file_num_compaction_trigger = kFilesPerLevel;
   options.max_subcompactions = 4;
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumPerFile));
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(kNumPerFile));
   options.num_levels = kNumLevels;
   options.target_file_size_base = kNumPerFile << 10;
   options.target_file_size_multiplier = 1;
@@ -489,7 +489,7 @@ TEST_F(DBRangeDelTest, CompactionRemovesCoveredMergeOperands) {
   const int kNumPerFile = 3, kNumFiles = 3;
   Options opts = CurrentOptions();
   opts.disable_auto_compactions = true;
-  opts.memtable_factory.reset(new SpecialSkipListFactory(2 * kNumPerFile));
+  opts.memtable_factory.reset(test::NewSpecialSkipListFactory(2 * kNumPerFile));
   opts.merge_operator = MergeOperators::CreateUInt64AddOperator();
   opts.num_levels = 2;
   Reopen(opts);
@@ -613,7 +613,7 @@ TEST_F(DBRangeDelTest, TableEvictedDuringScan) {
   opts.comparator = test::Uint64Comparator();
   opts.level0_file_num_compaction_trigger = 4;
   opts.level0_stop_writes_trigger = 4;
-  opts.memtable_factory.reset(new SpecialSkipListFactory(1));
+  opts.memtable_factory.reset(test::NewSpecialSkipListFactory(1));
   opts.num_levels = 2;
   BlockBasedTableOptions bbto;
   bbto.cache_index_and_filter_blocks = true;
@@ -694,7 +694,7 @@ TEST_F(DBRangeDelTest, GetCoveredKeyFromImmutableMemtable) {
     // memtable can hold. It switches the active memtable to immutable (flush is
     // prevented by the above options) upon inserting an element that would
     // overflow the memtable.
-    opts.memtable_factory.reset(new SpecialSkipListFactory(1));
+    opts.memtable_factory.reset(test::NewSpecialSkipListFactory(1));
     DestroyAndReopen(opts);
 
     ASSERT_OK(db_->Put(WriteOptions(), "key", "val"));
@@ -759,7 +759,7 @@ TEST_F(DBRangeDelTest, GetIgnoresRangeDeletions) {
   Options opts = CurrentOptions();
   opts.max_write_buffer_number = 4;
   opts.min_write_buffer_number_to_merge = 3;
-  opts.memtable_factory.reset(new SpecialSkipListFactory(1));
+  opts.memtable_factory.reset(test::NewSpecialSkipListFactory(1));
   Reopen(opts);
 
   ASSERT_OK(db_->Put(WriteOptions(), "sst_key", "val"));
@@ -788,7 +788,7 @@ TEST_F(DBRangeDelTest, IteratorRemovesCoveredKeys) {
   const int kNum = 200, kRangeBegin = 50, kRangeEnd = 150, kNumPerFile = 25;
   Options opts = CurrentOptions();
   opts.comparator = test::Uint64Comparator();
-  opts.memtable_factory.reset(new SpecialSkipListFactory(kNumPerFile));
+  opts.memtable_factory.reset(test::NewSpecialSkipListFactory(kNumPerFile));
   DestroyAndReopen(opts);
 
   // Write half of the keys before the tombstone and half after the tombstone.
@@ -823,7 +823,7 @@ TEST_F(DBRangeDelTest, IteratorOverUserSnapshot) {
   const int kNum = 200, kRangeBegin = 50, kRangeEnd = 150, kNumPerFile = 25;
   Options opts = CurrentOptions();
   opts.comparator = test::Uint64Comparator();
-  opts.memtable_factory.reset(new SpecialSkipListFactory(kNumPerFile));
+  opts.memtable_factory.reset(test::NewSpecialSkipListFactory(kNumPerFile));
   DestroyAndReopen(opts);
 
   const Snapshot* snapshot = nullptr;
@@ -857,7 +857,7 @@ TEST_F(DBRangeDelTest, IteratorIgnoresRangeDeletions) {
   Options opts = CurrentOptions();
   opts.max_write_buffer_number = 4;
   opts.min_write_buffer_number_to_merge = 3;
-  opts.memtable_factory.reset(new SpecialSkipListFactory(1));
+  opts.memtable_factory.reset(test::NewSpecialSkipListFactory(1));
   Reopen(opts);
 
   ASSERT_OK(db_->Put(WriteOptions(), "sst_key", "val"));
@@ -1005,7 +1005,7 @@ TEST_F(DBRangeDelTest, CompactionTreatsSplitInputLevelDeletionAtomically) {
   options.compression = kNoCompression;
   options.level0_file_num_compaction_trigger = kNumFilesPerLevel;
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(2 /* num_entries_flush */));
+      test::NewSpecialSkipListFactory(2 /* num_entries_flush */));
   options.target_file_size_base = kValueBytes;
   // i == 0: CompactFiles
   // i == 1: CompactRange
@@ -1073,7 +1073,7 @@ TEST_F(DBRangeDelTest, RangeTombstoneEndKeyAsSstableUpperBound) {
   options.compression = kNoCompression;
   options.level0_file_num_compaction_trigger = kNumFilesPerLevel;
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(2 /* num_entries_flush */));
+      test::NewSpecialSkipListFactory(2 /* num_entries_flush */));
   options.target_file_size_base = kValueBytes;
   options.disable_auto_compactions = true;
 

db/db_secondary_test.cc

@@ -12,6 +12,7 @@
 #include "port/stack_trace.h"
 #include "rocksdb/utilities/transaction_db.h"
 #include "test_util/sync_point.h"
+#include "test_util/testutil.h"
 #include "utilities/fault_injection_env.h"
 
 namespace ROCKSDB_NAMESPACE {
@@ -937,7 +938,7 @@ TEST_F(DBSecondaryTest, DISABLED_SwitchWAL) {
   options.max_write_buffer_number = 4;
   options.min_write_buffer_number_to_merge = 2;
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(kNumKeysPerMemtable));
+      test::NewSpecialSkipListFactory(kNumKeysPerMemtable));
   Reopen(options);
 
   Options options1;
@@ -992,7 +993,7 @@ TEST_F(DBSecondaryTest, DISABLED_SwitchWALMultiColumnFamilies) {
   options.max_write_buffer_number = 4;
   options.min_write_buffer_number_to_merge = 2;
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(kNumKeysPerMemtable));
+      test::NewSpecialSkipListFactory(kNumKeysPerMemtable));
   CreateAndReopenWithCF({kCFName1}, options);
 
   Options options1;
@@ -1056,7 +1057,7 @@ TEST_F(DBSecondaryTest, CatchUpAfterFlush) {
   options.max_write_buffer_number = 4;
   options.min_write_buffer_number_to_merge = 2;
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(kNumKeysPerMemtable));
+      test::NewSpecialSkipListFactory(kNumKeysPerMemtable));
   Reopen(options);
 
   Options options1;

db/db_test.cc

@@ -34,7 +34,6 @@
 #include "db/write_batch_internal.h"
 #include "env/mock_env.h"
 #include "file/filename.h"
-#include "memtable/hash_linklist_rep.h"
 #include "monitoring/thread_status_util.h"
 #include "port/port.h"
 #include "port/stack_trace.h"
@@ -5732,8 +5731,8 @@ TEST_F(DBTest, DISABLED_SuggestCompactRangeTest) {
   };
 
   Options options = CurrentOptions();
-  options.memtable_factory.reset(
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(
-      new SpecialSkipListFactory(DBTestBase::kNumKeysByGenerateNewRandomFile));
+      DBTestBase::kNumKeysByGenerateNewRandomFile));
   options.compaction_style = kCompactionStyleLevel;
   options.compaction_filter_factory.reset(
       new CompactionFilterFactoryGetContext());
@@ -6138,7 +6137,7 @@ TEST_F(DBTest, DelayedWriteRate) {
   options.level0_stop_writes_trigger = 999999;
   options.delayed_write_rate = 20000000;  // Start with 200MB/s
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(kEntriesPerMemTable));
+      test::NewSpecialSkipListFactory(kEntriesPerMemTable));
 
   SetTimeElapseOnlySleepOnReopen(&options);
   CreateAndReopenWithCF({"pikachu"}, options);
@@ -6201,7 +6200,7 @@ TEST_F(DBTest, HardLimit) {
   options.max_bytes_for_level_base = 10000000000u;
   options.max_background_compactions = 1;
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
+      test::NewSpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
 
   env_->SetBackgroundThreads(1, Env::LOW);
   test::SleepingBackgroundTask sleeping_task_low;
@@ -6450,7 +6449,7 @@ TEST_F(DBTest, LastWriteBufferDelay) {
   options.disable_auto_compactions = true;
   int kNumKeysPerMemtable = 3;
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(kNumKeysPerMemtable));
+      test::NewSpecialSkipListFactory(kNumKeysPerMemtable));
 
   Reopen(options);
   test::SleepingBackgroundTask sleeping_task;

db/db_test2.cc

@@ -22,6 +22,7 @@
 #include "rocksdb/trace_record_result.h"
 #include "rocksdb/utilities/replayer.h"
 #include "rocksdb/wal_filter.h"
+#include "test_util/testutil.h"
 #include "util/random.h"
 #include "utilities/fault_injection_env.h"
 
@@ -1264,7 +1265,7 @@ TEST_F(DBTest2, PresetCompressionDict) {
   options.disable_auto_compactions = true;
   options.level0_file_num_compaction_trigger = kNumL0Files;
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(kL0FileBytes / kBlockSizeBytes));
+      test::NewSpecialSkipListFactory(kL0FileBytes / kBlockSizeBytes));
   options.num_levels = 2;
   options.target_file_size_base = kL0FileBytes;
   options.target_file_size_multiplier = 2;
@@ -1484,7 +1485,7 @@ TEST_P(PresetCompressionDictTest, Flush) {
     options.compression_opts.max_dict_bytes = kDictLen;
     options.compression_opts.max_dict_buffer_bytes = kBlockLen;
   }
-  options.memtable_factory.reset(new SpecialSkipListFactory(kKeysPerFile));
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(kKeysPerFile));
   options.statistics = CreateDBStatistics();
   BlockBasedTableOptions bbto;
   bbto.block_size = kBlockLen;
@@ -2319,8 +2320,8 @@ INSTANTIATE_TEST_CASE_P(PinL0IndexAndFilterBlocksTest,
 #ifndef ROCKSDB_LITE
 TEST_F(DBTest2, MaxCompactionBytesTest) {
   Options options = CurrentOptions();
-  options.memtable_factory.reset(
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(
-      new SpecialSkipListFactory(DBTestBase::kNumKeysByGenerateNewRandomFile));
+      DBTestBase::kNumKeysByGenerateNewRandomFile));
   options.compaction_style = kCompactionStyleLevel;
   options.write_buffer_size = 200 << 10;
   options.arena_block_size = 4 << 10;
@@ -3945,7 +3946,8 @@ TEST_F(DBTest2, RateLimitedCompactionReads) {
     Options options = CurrentOptions();
     options.compression = kNoCompression;
     options.level0_file_num_compaction_trigger = kNumL0Files;
-    options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+    options.memtable_factory.reset(
+        test::NewSpecialSkipListFactory(kNumKeysPerFile));
     options.new_table_reader_for_compaction_inputs = true;
     // takes roughly one second, split into 100 x 10ms intervals. Each interval
     // permits 5.12KB, which is smaller than the block size, so this test

db/db_test_util.h

@@ -24,7 +24,6 @@
 #include "db/db_impl/db_impl.h"
 #include "db/dbformat.h"
 #include "file/filename.h"
-#include "memtable/hash_linklist_rep.h"
 #include "rocksdb/cache.h"
 #include "rocksdb/compaction_filter.h"
 #include "rocksdb/convenience.h"
@@ -112,94 +111,6 @@ struct OptionsOverride {
 
 enum SkipPolicy { kSkipNone = 0, kSkipNoSnapshot = 1, kSkipNoPrefix = 2 };
 
-// A hacky skip list mem table that triggers flush after number of entries.
-class SpecialMemTableRep : public MemTableRep {
- public:
-  explicit SpecialMemTableRep(Allocator* allocator, MemTableRep* memtable,
-                              int num_entries_flush)
-      : MemTableRep(allocator),
-        memtable_(memtable),
-        num_entries_flush_(num_entries_flush),
-        num_entries_(0) {}
-
-  virtual KeyHandle Allocate(const size_t len, char** buf) override {
-    return memtable_->Allocate(len, buf);
-  }
-
-  // Insert key into the list.
-  // REQUIRES: nothing that compares equal to key is currently in the list.
-  virtual void Insert(KeyHandle handle) override {
-    num_entries_++;
-    memtable_->Insert(handle);
-  }
-
-  void InsertConcurrently(KeyHandle handle) override {
-    num_entries_++;
-    memtable_->Insert(handle);
-  }
-
-  // Returns true iff an entry that compares equal to key is in the list.
-  virtual bool Contains(const char* key) const override {
-    return memtable_->Contains(key);
-  }
-
-  virtual size_t ApproximateMemoryUsage() override {
-    // Return a high memory usage when number of entries exceeds the threshold
-    // to trigger a flush.
-    return (num_entries_ < num_entries_flush_) ? 0 : 1024 * 1024 * 1024;
-  }
-
-  virtual void Get(const LookupKey& k, void* callback_args,
-                   bool (*callback_func)(void* arg,
-                                         const char* entry)) override {
-    memtable_->Get(k, callback_args, callback_func);
-  }
-
-  uint64_t ApproximateNumEntries(const Slice& start_ikey,
-                                 const Slice& end_ikey) override {
-    return memtable_->ApproximateNumEntries(start_ikey, end_ikey);
-  }
-
-  virtual MemTableRep::Iterator* GetIterator(Arena* arena = nullptr) override {
-    return memtable_->GetIterator(arena);
-  }
-
-  virtual ~SpecialMemTableRep() override {}
-
- private:
-  std::unique_ptr<MemTableRep> memtable_;
-  int num_entries_flush_;
-  int num_entries_;
-};
-
-// The factory for the hacky skip list mem table that triggers flush after
-// number of entries exceeds a threshold.
-class SpecialSkipListFactory : public MemTableRepFactory {
- public:
-  // After number of inserts exceeds `num_entries_flush` in a mem table, trigger
-  // flush.
-  explicit SpecialSkipListFactory(int num_entries_flush)
-      : num_entries_flush_(num_entries_flush) {}
-
-  using MemTableRepFactory::CreateMemTableRep;
-  virtual MemTableRep* CreateMemTableRep(
-      const MemTableRep::KeyComparator& compare, Allocator* allocator,
-      const SliceTransform* transform, Logger* /*logger*/) override {
-    return new SpecialMemTableRep(
-        allocator, factory_.CreateMemTableRep(compare, allocator, transform, 0),
-        num_entries_flush_);
-  }
-  virtual const char* Name() const override { return "SkipListFactory"; }
-
-  bool IsInsertConcurrentlySupported() const override {
-    return factory_.IsInsertConcurrentlySupported();
-  }
-
- private:
-  SkipListFactory factory_;
-  int num_entries_flush_;
-};
-
 // Special Env used to delay background operations
 class SpecialEnv : public EnvWrapper {
  public:

db/db_universal_compaction_test.cc

@@ -12,6 +12,7 @@
 #if !defined(ROCKSDB_LITE)
 #include "rocksdb/utilities/table_properties_collectors.h"
 #include "test_util/sync_point.h"
+#include "test_util/testutil.h"
 #include "util/random.h"
 
 namespace ROCKSDB_NAMESPACE {
@@ -151,7 +152,7 @@ TEST_P(DBTestUniversalCompaction, OptimizeFiltersForHits) {
   options.table_factory.reset(NewBlockBasedTableFactory(bbto));
   options.optimize_filters_for_hits = true;
   options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
-  options.memtable_factory.reset(new SpecialSkipListFactory(3));
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(3));
 
   DestroyAndReopen(options);
 
@@ -1230,7 +1231,7 @@ TEST_P(DBTestUniversalCompaction, UniversalCompactionFourPaths) {
   options.db_paths.emplace_back(dbname_ + "_3", 500 * 1024);
   options.db_paths.emplace_back(dbname_ + "_4", 1024 * 1024 * 1024);
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
+      test::NewSpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
   options.compaction_style = kCompactionStyleUniversal;
   options.compaction_options_universal.size_ratio = 5;
   options.write_buffer_size = 111 << 10;  // 114KB
@@ -1334,7 +1335,7 @@ TEST_P(DBTestUniversalCompaction, UniversalCompactionCFPathUse) {
   options.db_paths.emplace_back(dbname_ + "_3", 500 * 1024);
   options.db_paths.emplace_back(dbname_ + "_4", 1024 * 1024 * 1024);
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
+      test::NewSpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
   options.compaction_style = kCompactionStyleUniversal;
   options.compaction_options_universal.size_ratio = 10;
   options.write_buffer_size = 111 << 10;  // 114KB
@@ -1498,7 +1499,8 @@ TEST_P(DBTestUniversalCompaction, IncreaseUniversalCompactionNumLevels) {
   options.num_levels = 1;
   options.write_buffer_size = 200 << 10;  // 200KB
   options.level0_file_num_compaction_trigger = 3;
-  options.memtable_factory.reset(new SpecialSkipListFactory(KNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(KNumKeysPerFile));
   options = CurrentOptions(options);
   CreateAndReopenWithCF({"pikachu"}, options);
 
@@ -1579,7 +1581,7 @@ TEST_P(DBTestUniversalCompaction, UniversalCompactionSecondPathRatio) {
   options.level0_file_num_compaction_trigger = 2;
   options.num_levels = 1;
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
+      test::NewSpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
 
   std::vector<std::string> filenames;
   if (env_->GetChildren(options.db_paths[1].path, &filenames).ok()) {
@@ -1729,7 +1731,7 @@ TEST_P(DBTestUniversalCompaction, RecalculateScoreAfterPicking) {
   const int kNumFilesTrigger = 8;
   Options options = CurrentOptions();
   options.memtable_factory.reset(
-      new SpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
+      test::NewSpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
   options.compaction_options_universal.max_merge_width = kNumFilesTrigger / 2;
   options.compaction_options_universal.max_size_amplification_percent =
       static_cast<unsigned int>(-1);

db/db_with_timestamp_basic_test.cc

@@ -16,6 +16,7 @@
 #if !defined(ROCKSDB_LITE)
 #include "test_util/sync_point.h"
 #endif
+#include "test_util/testutil.h"
 #include "utilities/fault_injection_env.h"
 
 namespace ROCKSDB_NAMESPACE {
@@ -415,7 +416,8 @@ TEST_F(DBBasicTestWithTimestamp, SimpleIterate) {
   const size_t kTimestampSize = Timestamp(0, 0).size();
   TestComparator test_cmp(kTimestampSize);
   options.comparator = &test_cmp;
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeysPerFile));
   DestroyAndReopen(options);
   const std::vector<uint64_t> start_keys = {1, 0};
   const std::vector<std::string> write_timestamps = {Timestamp(1, 0),
@@ -842,7 +844,8 @@ TEST_F(DBBasicTestWithTimestamp, SimpleForwardIterateLowerTsBound) {
   const size_t kTimestampSize = Timestamp(0, 0).size();
   TestComparator test_cmp(kTimestampSize);
   options.comparator = &test_cmp;
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeysPerFile));
   DestroyAndReopen(options);
   const std::vector<std::string> write_timestamps = {Timestamp(1, 0),
                                                      Timestamp(3, 0)};
@@ -927,7 +930,8 @@ TEST_F(DBBasicTestWithTimestamp, ForwardIterateStartSeqnum) {
   const size_t kTimestampSize = Timestamp(0, 0).size();
   TestComparator test_cmp(kTimestampSize);
   options.comparator = &test_cmp;
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeysPerFile));
   DestroyAndReopen(options);
   std::vector<SequenceNumber> start_seqs;
 
@@ -2235,7 +2239,8 @@ TEST_P(DBBasicTestWithTimestampCompressionSettings, PutAndGet) {
   Options options = CurrentOptions();
   options.create_if_missing = true;
   options.env = env_;
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeysPerFile));
   size_t ts_sz = Timestamp(0, 0).size();
   TestComparator test_cmp(ts_sz);
   options.comparator = &test_cmp;
@@ -2313,7 +2318,8 @@ TEST_P(DBBasicTestWithTimestampCompressionSettings, PutDeleteGet) {
   TestComparator test_cmp(kTimestampSize);
   options.comparator = &test_cmp;
   const int kNumKeysPerFile = 1024;
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeysPerFile));
   BlockBasedTableOptions bbto;
   bbto.filter_policy = std::get<0>(GetParam());
   bbto.whole_key_filtering = true;
@@ -2442,7 +2448,8 @@ TEST_P(DBBasicTestWithTimestampCompressionSettings, PutAndGetWithCompaction) {
   Options options = CurrentOptions();
   options.create_if_missing = true;
   options.env = env_;
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeysPerFile));
 
   FlushedFileCollector* collector = new FlushedFileCollector();
   options.listeners.emplace_back(collector);
@@ -2558,7 +2565,8 @@ TEST_F(DBBasicTestWithTimestamp, BatchWriteAndMultiGet) {
   Options options = CurrentOptions();
   options.create_if_missing = true;
   options.env = env_;
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeysPerFile));
   options.memtable_prefix_bloom_size_ratio = 0.1;
   options.memtable_whole_key_filtering = true;
 
@@ -2725,7 +2733,8 @@ TEST_P(DBBasicTestWithTimestampPrefixSeek, IterateWithPrefix) {
   TestComparator test_cmp(kTimestampSize);
   options.comparator = &test_cmp;
   options.prefix_extractor = std::get<0>(GetParam());
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeysPerFile));
   BlockBasedTableOptions bbto;
   bbto.filter_policy = std::get<1>(GetParam());
   bbto.index_type = std::get<3>(GetParam());
@@ -2879,7 +2888,8 @@ TEST_P(DBBasicTestWithTsIterTombstones, IterWithDelete) {
   TestComparator test_cmp(kTimestampSize);
   options.comparator = &test_cmp;
   options.prefix_extractor = std::get<0>(GetParam());
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeysPerFile));
   BlockBasedTableOptions bbto;
   bbto.filter_policy = std::get<1>(GetParam());
   bbto.index_type = std::get<3>(GetParam());

db/db_with_timestamp_compaction_test.cc

@@ -10,6 +10,7 @@
 #include "db/compaction/compaction.h"
 #include "db/db_test_util.h"
 #include "port/stack_trace.h"
+#include "test_util/testutil.h"
 
 namespace ROCKSDB_NAMESPACE {
 
@@ -56,7 +57,8 @@ TEST_F(TimestampCompatibleCompactionTest, UserKeyCrossFileBoundary) {
   options.comparator = test::ComparatorWithU64Ts();
   options.level0_file_num_compaction_trigger = 3;
   constexpr size_t kNumKeysPerFile = 101;
-  options.memtable_factory.reset(new SpecialSkipListFactory(kNumKeysPerFile));
+  options.memtable_factory.reset(
+      test::NewSpecialSkipListFactory(kNumKeysPerFile));
   DestroyAndReopen(options);
   SyncPoint::GetInstance()->DisableProcessing();
   SyncPoint::GetInstance()->ClearAllCallBacks();

db/listener_test.cc

@@ -10,7 +10,6 @@
 #include "db/version_set.h"
 #include "db/write_batch_internal.h"
 #include "file/filename.h"
-#include "memtable/hash_linklist_rep.h"
 #include "monitoring/statistics.h"
 #include "rocksdb/cache.h"
 #include "rocksdb/compaction_filter.h"
@@ -529,8 +528,8 @@ TEST_F(EventListenerTest, CompactionReasonLevel) {
   Options options;
   options.env = CurrentOptions().env;
   options.create_if_missing = true;
-  options.memtable_factory.reset(
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(
-      new SpecialSkipListFactory(DBTestBase::kNumKeysByGenerateNewRandomFile));
+      DBTestBase::kNumKeysByGenerateNewRandomFile));
 
   TestCompactionReasonListener* listener = new TestCompactionReasonListener();
   options.listeners.emplace_back(listener);
@@ -595,8 +594,8 @@ TEST_F(EventListenerTest, CompactionReasonUniversal) {
   Options options;
   options.env = CurrentOptions().env;
   options.create_if_missing = true;
-  options.memtable_factory.reset(
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(
-      new SpecialSkipListFactory(DBTestBase::kNumKeysByGenerateNewRandomFile));
+      DBTestBase::kNumKeysByGenerateNewRandomFile));
 
   TestCompactionReasonListener* listener = new TestCompactionReasonListener();
   options.listeners.emplace_back(listener);
@@ -657,8 +656,8 @@ TEST_F(EventListenerTest, CompactionReasonFIFO) {
   Options options;
   options.env = CurrentOptions().env;
   options.create_if_missing = true;
-  options.memtable_factory.reset(
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(
-      new SpecialSkipListFactory(DBTestBase::kNumKeysByGenerateNewRandomFile));
+      DBTestBase::kNumKeysByGenerateNewRandomFile));
 
   TestCompactionReasonListener* listener = new TestCompactionReasonListener();
   options.listeners.emplace_back(listener);
@@ -925,7 +924,7 @@ TEST_F(EventListenerTest, BackgroundErrorListenerFailedFlushTest) {
   options.create_if_missing = true;
   options.env = env_;
   options.listeners.push_back(listener);
-  options.memtable_factory.reset(new SpecialSkipListFactory(1));
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(1));
   options.paranoid_checks = true;
   DestroyAndReopen(options);
 
@@ -956,7 +955,7 @@ TEST_F(EventListenerTest, BackgroundErrorListenerFailedCompactionTest) {
   options.env = env_;
   options.level0_file_num_compaction_trigger = 2;
   options.listeners.push_back(listener);
-  options.memtable_factory.reset(new SpecialSkipListFactory(2));
+  options.memtable_factory.reset(test::NewSpecialSkipListFactory(2));
   options.paranoid_checks = true;
   DestroyAndReopen(options);
 

include/rocksdb/memtablerep.h

@@ -42,6 +42,7 @@
 #include <stdexcept>
 #include <unordered_set>
 
+#include "rocksdb/customizable.h"
 #include "rocksdb/slice.h"
 
 namespace ROCKSDB_NAMESPACE {
@@ -51,6 +52,7 @@ class Allocator;
 class LookupKey;
 class SliceTransform;
 class Logger;
+struct DBOptions;
 
 using KeyHandle = void*;
 
@@ -290,10 +292,15 @@ class MemTableRep {
 
 // This is the base class for all factories that are used by RocksDB to create
 // new MemTableRep objects
-class MemTableRepFactory {
+class MemTableRepFactory : public Customizable {
  public:
   virtual ~MemTableRepFactory() {}
 
+  static const char* Type() { return "MemTableRepFactory"; }
+  static Status CreateFromString(const ConfigOptions& config_options,
+                                 const std::string& id,
+                                 std::unique_ptr<MemTableRepFactory>* factory);
+
   virtual MemTableRep* CreateMemTableRep(const MemTableRep::KeyComparator&,
                                          Allocator*, const SliceTransform*,
                                          Logger* logger) = 0;
@@ -326,20 +333,27 @@ class MemTableRepFactory {
 //     seeks with consecutive keys.
 class SkipListFactory : public MemTableRepFactory {
  public:
-  explicit SkipListFactory(size_t lookahead = 0) : lookahead_(lookahead) {}
+  explicit SkipListFactory(size_t lookahead = 0);
 
+  // Methods for Configurable/Customizable class overrides
+  static const char* kClassName() { return "SkipListFactory"; }
+  static const char* kNickName() { return "skip_list"; }
+  virtual const char* Name() const override { return kClassName(); }
+  virtual const char* NickName() const override { return kNickName(); }
+  std::string GetId() const override;
+
+  // Methods for MemTableRepFactory class overrides
   using MemTableRepFactory::CreateMemTableRep;
   virtual MemTableRep* CreateMemTableRep(const MemTableRep::KeyComparator&,
                                          Allocator*, const SliceTransform*,
                                          Logger* logger) override;
-  virtual const char* Name() const override { return "SkipListFactory"; }
 
   bool IsInsertConcurrentlySupported() const override { return true; }
 
   bool CanHandleDuplicatedKey() const override { return true; }
 
  private:
-  const size_t lookahead_;
+  size_t lookahead_;
 };
 
 #ifndef ROCKSDB_LITE
@@ -352,17 +366,22 @@ class SkipListFactory : public MemTableRepFactory {
 //     VectorRep. On initialization, the underlying array will be at least count
 //     bytes reserved for usage.
 class VectorRepFactory : public MemTableRepFactory {
-  const size_t count_;
+  size_t count_;
 
  public:
-  explicit VectorRepFactory(size_t count = 0) : count_(count) {}
+  explicit VectorRepFactory(size_t count = 0);
 
+  // Methods for Configurable/Customizable class overrides
+  static const char* kClassName() { return "VectorRepFactory"; }
+  static const char* kNickName() { return "vector"; }
+  const char* Name() const override { return kClassName(); }
+  const char* NickName() const override { return kNickName(); }
+
+  // Methods for MemTableRepFactory class overrides
   using MemTableRepFactory::CreateMemTableRep;
   virtual MemTableRep* CreateMemTableRep(const MemTableRep::KeyComparator&,
                                          Allocator*, const SliceTransform*,
                                          Logger* logger) override;
-
-  virtual const char* Name() const override { return "VectorRepFactory"; }
 };
 
 // This class contains a fixed array of buckets, each

include/rocksdb/utilities/options_type.h

@@ -36,7 +36,6 @@ enum class OptionType {
   kSliceTransform,
   kCompressionType,
   kCompactionStopStyle,
-  kMemTableRepFactory,
   kFilterPolicy,
   kChecksumType,
   kEncodingType,

memtable/hash_linklist_rep.cc

@@ -5,10 +5,10 @@
 //
 
 #ifndef ROCKSDB_LITE
-#include "memtable/hash_linklist_rep.h"
 
 #include <algorithm>
 #include <atomic>
+
 #include "db/memtable.h"
 #include "memory/arena.h"
 #include "memtable/skiplist.h"
@@ -17,6 +17,7 @@
 #include "rocksdb/memtablerep.h"
 #include "rocksdb/slice.h"
 #include "rocksdb/slice_transform.h"
+#include "rocksdb/utilities/options_type.h"
 #include "util/hash.h"
 
 namespace ROCKSDB_NAMESPACE {
@@ -820,15 +821,77 @@ Node* HashLinkListRep::FindGreaterOrEqualInBucket(Node* head,
   return x;
 }
 
-} // anon namespace
+struct HashLinkListRepOptions {
+  static const char* kName() { return "HashLinkListRepFactoryOptions"; }
+  size_t bucket_count;
+  uint32_t threshold_use_skiplist;
+  size_t huge_page_tlb_size;
+  int bucket_entries_logging_threshold;
+  bool if_log_bucket_dist_when_flash;
+};
+
+static std::unordered_map<std::string, OptionTypeInfo> hash_linklist_info = {
+    {"bucket_count",
+     {offsetof(struct HashLinkListRepOptions, bucket_count), OptionType::kSizeT,
+      OptionVerificationType::kNormal, OptionTypeFlags::kNone}},
+    {"threshold",
+     {offsetof(struct HashLinkListRepOptions, threshold_use_skiplist),
+      OptionType::kUInt32T, OptionVerificationType::kNormal,
+      OptionTypeFlags::kNone}},
+    {"huge_page_size",
+     {offsetof(struct HashLinkListRepOptions, huge_page_tlb_size),
+      OptionType::kSizeT, OptionVerificationType::kNormal,
+      OptionTypeFlags::kNone}},
+    {"logging_threshold",
+     {offsetof(struct HashLinkListRepOptions, bucket_entries_logging_threshold),
+      OptionType::kInt, OptionVerificationType::kNormal,
+      OptionTypeFlags::kNone}},
+    {"log_when_flash",
+     {offsetof(struct HashLinkListRepOptions, if_log_bucket_dist_when_flash),
+      OptionType::kBoolean, OptionVerificationType::kNormal,
+      OptionTypeFlags::kNone}},
+};
+
+class HashLinkListRepFactory : public MemTableRepFactory {
+ public:
+  explicit HashLinkListRepFactory(size_t bucket_count,
+                                  uint32_t threshold_use_skiplist,
+                                  size_t huge_page_tlb_size,
+                                  int bucket_entries_logging_threshold,
+                                  bool if_log_bucket_dist_when_flash) {
+    options_.bucket_count = bucket_count;
+    options_.threshold_use_skiplist = threshold_use_skiplist;
+    options_.huge_page_tlb_size = huge_page_tlb_size;
+    options_.bucket_entries_logging_threshold =
+        bucket_entries_logging_threshold;
+    options_.if_log_bucket_dist_when_flash = if_log_bucket_dist_when_flash;
+    RegisterOptions(&options_, &hash_linklist_info);
+  }
+
+  using MemTableRepFactory::CreateMemTableRep;
+  virtual MemTableRep* CreateMemTableRep(
+      const MemTableRep::KeyComparator& compare, Allocator* allocator,
+      const SliceTransform* transform, Logger* logger) override;
+
+  static const char* kClassName() { return "HashLinkListRepFactory"; }
+  static const char* kNickName() { return "hash_linkedlist"; }
+  virtual const char* Name() const override { return kClassName(); }
+  virtual const char* NickName() const override { return kNickName(); }
+
+ private:
+  HashLinkListRepOptions options_;
+};
+
+}  // namespace
 
 MemTableRep* HashLinkListRepFactory::CreateMemTableRep(
     const MemTableRep::KeyComparator& compare, Allocator* allocator,
     const SliceTransform* transform, Logger* logger) {
-  return new HashLinkListRep(compare, allocator, transform, bucket_count_,
+  return new HashLinkListRep(
-                             threshold_use_skiplist_, huge_page_tlb_size_,
+      compare, allocator, transform, options_.bucket_count,
-                             logger, bucket_entries_logging_threshold_,
+      options_.threshold_use_skiplist, options_.huge_page_tlb_size, logger,
-                             if_log_bucket_dist_when_flash_);
+      options_.bucket_entries_logging_threshold,
+      options_.if_log_bucket_dist_when_flash);
 }
 
 MemTableRepFactory* NewHashLinkListRepFactory(

memtable/hash_linklist_rep.h

@@ -1,49 +0,0 @@
-// Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
-//  This source code is licensed under both the GPLv2 (found in the
-//  COPYING file in the root directory) and Apache 2.0 License
-//  (found in the LICENSE.Apache file in the root directory).
-// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file. See the AUTHORS file for names of contributors.
-
-#pragma once
-#ifndef ROCKSDB_LITE
-#include "rocksdb/slice_transform.h"
-#include "rocksdb/memtablerep.h"
-
-namespace ROCKSDB_NAMESPACE {
-
-class HashLinkListRepFactory : public MemTableRepFactory {
- public:
-  explicit HashLinkListRepFactory(size_t bucket_count,
-                                  uint32_t threshold_use_skiplist,
-                                  size_t huge_page_tlb_size,
-                                  int bucket_entries_logging_threshold,
-                                  bool if_log_bucket_dist_when_flash)
-      : bucket_count_(bucket_count),
-        threshold_use_skiplist_(threshold_use_skiplist),
-        huge_page_tlb_size_(huge_page_tlb_size),
-        bucket_entries_logging_threshold_(bucket_entries_logging_threshold),
-        if_log_bucket_dist_when_flash_(if_log_bucket_dist_when_flash) {}
-
-  virtual ~HashLinkListRepFactory() {}
-
-  using MemTableRepFactory::CreateMemTableRep;
-  virtual MemTableRep* CreateMemTableRep(
-      const MemTableRep::KeyComparator& compare, Allocator* allocator,
-      const SliceTransform* transform, Logger* logger) override;
-
-  virtual const char* Name() const override {
-    return "HashLinkListRepFactory";
-  }
-
- private:
-  const size_t bucket_count_;
-  const uint32_t threshold_use_skiplist_;
-  const size_t huge_page_tlb_size_;
-  int bucket_entries_logging_threshold_;
-  bool if_log_bucket_dist_when_flash_;
-};
-
-}  // namespace ROCKSDB_NAMESPACE
-#endif  // ROCKSDB_LITE

memtable/hash_skiplist_rep.cc

@@ -5,8 +5,6 @@
 //
 
 #ifndef ROCKSDB_LITE
-#include "memtable/hash_skiplist_rep.h"
-
 #include <atomic>
 
 #include "db/memtable.h"
@@ -16,6 +14,7 @@
 #include "rocksdb/memtablerep.h"
 #include "rocksdb/slice.h"
 #include "rocksdb/slice_transform.h"
+#include "rocksdb/utilities/options_type.h"
 #include "util/murmurhash.h"
 
 namespace ROCKSDB_NAMESPACE {
@@ -329,13 +328,60 @@ MemTableRep::Iterator* HashSkipListRep::GetDynamicPrefixIterator(Arena* arena) {
   }
 }
 
-} // anon namespace
+struct HashSkipListRepOptions {
+  static const char* kName() { return "HashSkipListRepFactoryOptions"; }
+  size_t bucket_count;
+  int32_t skiplist_height;
+  int32_t skiplist_branching_factor;
+};
+
+static std::unordered_map<std::string, OptionTypeInfo> hash_skiplist_info = {
+    {"bucket_count",
+     {offsetof(struct HashSkipListRepOptions, bucket_count), OptionType::kSizeT,
+      OptionVerificationType::kNormal, OptionTypeFlags::kNone}},
+    {"skiplist_height",
+     {offsetof(struct HashSkipListRepOptions, skiplist_height),
+      OptionType::kInt32T, OptionVerificationType::kNormal,
+      OptionTypeFlags::kNone}},
+    {"branching_factor",
+     {offsetof(struct HashSkipListRepOptions, skiplist_branching_factor),
+      OptionType::kInt32T, OptionVerificationType::kNormal,
+      OptionTypeFlags::kNone}},
+};
+
+class HashSkipListRepFactory : public MemTableRepFactory {
+ public:
+  explicit HashSkipListRepFactory(size_t bucket_count, int32_t skiplist_height,
+                                  int32_t skiplist_branching_factor) {
+    options_.bucket_count = bucket_count;
+    options_.skiplist_height = skiplist_height;
+    options_.skiplist_branching_factor = skiplist_branching_factor;
+    RegisterOptions(&options_, &hash_skiplist_info);
+  }
+
+  using MemTableRepFactory::CreateMemTableRep;
+  virtual MemTableRep* CreateMemTableRep(
+      const MemTableRep::KeyComparator& compare, Allocator* allocator,
+      const SliceTransform* transform, Logger* logger) override;
+
+  static const char* kClassName() { return "HashSkipListRepFactory"; }
+  static const char* kNickName() { return "prefix_hash"; }
+
+  virtual const char* Name() const override { return kClassName(); }
+  virtual const char* NickName() const override { return kNickName(); }
+
+ private:
+  HashSkipListRepOptions options_;
+};
+
+}  // namespace
 
 MemTableRep* HashSkipListRepFactory::CreateMemTableRep(
     const MemTableRep::KeyComparator& compare, Allocator* allocator,
     const SliceTransform* transform, Logger* /*logger*/) {
-  return new HashSkipListRep(compare, allocator, transform, bucket_count_,
+  return new HashSkipListRep(compare, allocator, transform,
-                             skiplist_height_, skiplist_branching_factor_);
+                             options_.bucket_count, options_.skiplist_height,
+                             options_.skiplist_branching_factor);
 }
 
 MemTableRepFactory* NewHashSkipListRepFactory(

memtable/hash_skiplist_rep.h

@@ -1,44 +0,0 @@
-// Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
-//  This source code is licensed under both the GPLv2 (found in the
-//  COPYING file in the root directory) and Apache 2.0 License
-//  (found in the LICENSE.Apache file in the root directory).
-// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file. See the AUTHORS file for names of contributors.
-
-#pragma once
-#ifndef ROCKSDB_LITE
-#include "rocksdb/slice_transform.h"
-#include "rocksdb/memtablerep.h"
-
-namespace ROCKSDB_NAMESPACE {
-
-class HashSkipListRepFactory : public MemTableRepFactory {
- public:
-  explicit HashSkipListRepFactory(
-    size_t bucket_count,
-    int32_t skiplist_height,
-    int32_t skiplist_branching_factor)
-      : bucket_count_(bucket_count),
-        skiplist_height_(skiplist_height),
-        skiplist_branching_factor_(skiplist_branching_factor) { }
-
-  virtual ~HashSkipListRepFactory() {}
-
-  using MemTableRepFactory::CreateMemTableRep;
-  virtual MemTableRep* CreateMemTableRep(
-      const MemTableRep::KeyComparator& compare, Allocator* allocator,
-      const SliceTransform* transform, Logger* logger) override;
-
-  virtual const char* Name() const override {
-    return "HashSkipListRepFactory";
-  }
-
- private:
-  const size_t bucket_count_;
-  const int32_t skiplist_height_;
-  const int32_t skiplist_branching_factor_;
-};
-
-}  // namespace ROCKSDB_NAMESPACE
-#endif  // ROCKSDB_LITE

memtable/memtablerep_bench.cc

@@ -28,6 +28,7 @@ int main() {
 #include "port/port.h"
 #include "port/stack_trace.h"
 #include "rocksdb/comparator.h"
+#include "rocksdb/convenience.h"
 #include "rocksdb/memtablerep.h"
 #include "rocksdb/options.h"
 #include "rocksdb/slice_transform.h"
@@ -581,13 +582,15 @@ int main(int argc, char** argv) {
 #ifndef ROCKSDB_LITE
   } else if (FLAGS_memtablerep == "vector") {
     factory.reset(new ROCKSDB_NAMESPACE::VectorRepFactory);
-  } else if (FLAGS_memtablerep == "hashskiplist") {
+  } else if (FLAGS_memtablerep == "hashskiplist" ||
+             FLAGS_memtablerep == "prefix_hash") {
     factory.reset(ROCKSDB_NAMESPACE::NewHashSkipListRepFactory(
         FLAGS_bucket_count, FLAGS_hashskiplist_height,
         FLAGS_hashskiplist_branching_factor));
     options.prefix_extractor.reset(
         ROCKSDB_NAMESPACE::NewFixedPrefixTransform(FLAGS_prefix_length));
-  } else if (FLAGS_memtablerep == "hashlinklist") {
+  } else if (FLAGS_memtablerep == "hashlinklist" ||
+             FLAGS_memtablerep == "hash_linkedlist") {
     factory.reset(ROCKSDB_NAMESPACE::NewHashLinkListRepFactory(
         FLAGS_bucket_count, FLAGS_huge_page_tlb_size,
         FLAGS_bucket_entries_logging_threshold,
@@ -596,9 +599,17 @@ int main(int argc, char** argv) {
         ROCKSDB_NAMESPACE::NewFixedPrefixTransform(FLAGS_prefix_length));
 #endif  // ROCKSDB_LITE
   } else {
-    fprintf(stdout, "Unknown memtablerep: %s\n", FLAGS_memtablerep.c_str());
+    ROCKSDB_NAMESPACE::ConfigOptions config_options;
+    config_options.ignore_unsupported_options = false;
+
+    ROCKSDB_NAMESPACE::Status s =
+        ROCKSDB_NAMESPACE::MemTableRepFactory::CreateFromString(
+            config_options, FLAGS_memtablerep, &factory);
+    if (!s.ok()) {
+      fprintf(stdout, "Unknown memtablerep: %s\n", s.ToString().c_str());
       exit(1);
     }
+  }
 
   ROCKSDB_NAMESPACE::InternalKeyComparator internal_key_comp(
       ROCKSDB_NAMESPACE::BytewiseComparator());

memtable/skiplistrep.cc

@@ -9,6 +9,8 @@
 #include "memory/arena.h"
 #include "memtable/inlineskiplist.h"
 #include "rocksdb/memtablerep.h"
+#include "rocksdb/utilities/options_type.h"
+#include "util/string_util.h"
 
 namespace ROCKSDB_NAMESPACE {
 namespace {
@@ -335,6 +337,27 @@ public:
 };
 }
 
+static std::unordered_map<std::string, OptionTypeInfo> skiplist_factory_info = {
+#ifndef ROCKSDB_LITE
+    {"lookahead",
+     {0, OptionType::kSizeT, OptionVerificationType::kNormal,
+      OptionTypeFlags::kDontSerialize /*Since it is part of the ID*/}},
+#endif
+};
+
+SkipListFactory::SkipListFactory(size_t lookahead) : lookahead_(lookahead) {
+  RegisterOptions("SkipListFactoryOptions", &lookahead_,
+                  &skiplist_factory_info);
+}
+
+std::string SkipListFactory::GetId() const {
+  std::string id = Name();
+  if (lookahead_ > 0) {
+    id.append(":").append(ROCKSDB_NAMESPACE::ToString(lookahead_));
+  }
+  return id;
+}
+
 MemTableRep* SkipListFactory::CreateMemTableRep(
     const MemTableRep::KeyComparator& compare, Allocator* allocator,
     const SliceTransform* transform, Logger* /*logger*/) {

memtable/vectorrep.cc

@@ -4,18 +4,18 @@
 //  (found in the LICENSE.Apache file in the root directory).
 //
 #ifndef ROCKSDB_LITE
-#include "rocksdb/memtablerep.h"
-
-#include <unordered_set>
-#include <set>
-#include <memory>
 #include <algorithm>
+#include <memory>
+#include <set>
 #include <type_traits>
+#include <unordered_set>
 
 #include "db/memtable.h"
 #include "memory/arena.h"
 #include "memtable/stl_wrappers.h"
 #include "port/port.h"
+#include "rocksdb/memtablerep.h"
+#include "rocksdb/utilities/options_type.h"
 #include "util/mutexlock.h"
 
 namespace ROCKSDB_NAMESPACE {
@@ -292,6 +292,16 @@ MemTableRep::Iterator* VectorRep::GetIterator(Arena* arena) {
 }
 } // anon namespace
 
+static std::unordered_map<std::string, OptionTypeInfo> vector_rep_table_info = {
+    {"count",
+     {0, OptionType::kSizeT, OptionVerificationType::kNormal,
+      OptionTypeFlags::kNone}},
+};
+
+VectorRepFactory::VectorRepFactory(size_t count) : count_(count) {
+  RegisterOptions("VectorRepFactoryOptions", &count_, &vector_rep_table_info);
+}
+
 MemTableRep* VectorRepFactory::CreateMemTableRep(
     const MemTableRep::KeyComparator& compare, Allocator* allocator,
     const SliceTransform*, Logger* /*logger*/) {

options/cf_options.cc

@@ -573,21 +573,33 @@ static std::unordered_map<std::string, OptionTypeInfo>
           OptionTypeFlags::kNone}},
         {"memtable_factory",
          {offset_of(&ImmutableCFOptions::memtable_factory),
-          OptionType::kMemTableRepFactory, OptionVerificationType::kByName,
+          OptionType::kCustomizable, OptionVerificationType::kByName,
-          OptionTypeFlags::kNone}},
+          OptionTypeFlags::kShared,
+          [](const ConfigOptions& opts, const std::string&,
+             const std::string& value, void* addr) {
+            std::unique_ptr<MemTableRepFactory> factory;
+            auto* shared =
+                static_cast<std::shared_ptr<MemTableRepFactory>*>(addr);
+            Status s =
+                MemTableRepFactory::CreateFromString(opts, value, &factory);
+            if (s.ok()) {
+              shared->reset(factory.release());
+            }
+            return s;
+          }}},
         {"memtable",
          {offset_of(&ImmutableCFOptions::memtable_factory),
-          OptionType::kMemTableRepFactory, OptionVerificationType::kAlias,
+          OptionType::kCustomizable, OptionVerificationType::kAlias,
-          OptionTypeFlags::kNone,
+          OptionTypeFlags::kShared,
-          // Parses the value string and updates the memtable_factory
+          [](const ConfigOptions& opts, const std::string&,
-          [](const ConfigOptions& /*opts*/, const std::string& /*name*/,
              const std::string& value, void* addr) {
-            std::unique_ptr<MemTableRepFactory> new_mem_factory;
+            std::unique_ptr<MemTableRepFactory> factory;
-            Status s = GetMemTableRepFactoryFromString(value, &new_mem_factory);
+            auto* shared =
-            if (s.ok()) {
-              auto memtable_factory =
                 static_cast<std::shared_ptr<MemTableRepFactory>*>(addr);
-              memtable_factory->reset(new_mem_factory.release());
+            Status s =
+                MemTableRepFactory::CreateFromString(opts, value, &factory);
+            if (s.ok()) {
+              shared->reset(factory.release());
             }
             return s;
           }}},

options/customizable_test.cc

@@ -1302,6 +1302,23 @@ TEST_F(LoadCustomizableTest, LoadComparatorTest) {
   }
 }
 
+TEST_F(LoadCustomizableTest, LoadMemTableRepFactoryTest) {
+  std::unique_ptr<MemTableRepFactory> result;
+  ASSERT_NOK(MemTableRepFactory::CreateFromString(
+      config_options_, "SpecialSkipListFactory", &result));
+  ASSERT_OK(MemTableRepFactory::CreateFromString(
+      config_options_, SkipListFactory::kClassName(), &result));
+  ASSERT_NE(result.get(), nullptr);
+  ASSERT_TRUE(result->IsInstanceOf(SkipListFactory::kClassName()));
+
+  if (RegisterTests("Test")) {
+    ASSERT_OK(MemTableRepFactory::CreateFromString(
+        config_options_, "SpecialSkipListFactory", &result));
+    ASSERT_NE(result, nullptr);
+    ASSERT_STREQ(result->Name(), "SpecialSkipListFactory");
+  }
+}
+
 TEST_F(LoadCustomizableTest, LoadMergeOperatorTest) {
   std::shared_ptr<MergeOperator> result;
 

options/options_helper.cc

@@ -562,12 +562,6 @@ bool SerializeSingleOptionHelper(const void* opt_address,
                                           : kNullptrString;
       break;
     }
-    case OptionType::kMemTableRepFactory: {
-      const auto* ptr =
-          static_cast<const std::shared_ptr<MemTableRepFactory>*>(opt_address);
-      *value = ptr->get() ? ptr->get()->Name() : kNullptrString;
-      break;
-    }
     case OptionType::kFilterPolicy: {
       const auto* ptr =
           static_cast<const std::shared_ptr<FilterPolicy>*>(opt_address);

options/options_test.cc

@@ -575,6 +575,7 @@ TEST_F(OptionsTest, GetColumnFamilyOptionsFromStringTest) {
       &new_cf_opt));
   ASSERT_TRUE(new_cf_opt.memtable_factory != nullptr);
   ASSERT_EQ(std::string(new_cf_opt.memtable_factory->Name()), "SkipListFactory");
+  ASSERT_TRUE(new_cf_opt.memtable_factory->IsInstanceOf("SkipListFactory"));
 }
 
 TEST_F(OptionsTest, CompressionOptionsFromString) {
@@ -1137,14 +1138,14 @@ TEST_F(OptionsTest, GetMemTableRepFactoryFromString) {
 
   ASSERT_OK(GetMemTableRepFactoryFromString("skip_list", &new_mem_factory));
   ASSERT_OK(GetMemTableRepFactoryFromString("skip_list:16", &new_mem_factory));
-  ASSERT_EQ(std::string(new_mem_factory->Name()), "SkipListFactory");
+  ASSERT_STREQ(new_mem_factory->Name(), "SkipListFactory");
   ASSERT_NOK(GetMemTableRepFactoryFromString("skip_list:16:invalid_opt",
                                              &new_mem_factory));
 
   ASSERT_OK(GetMemTableRepFactoryFromString("prefix_hash", &new_mem_factory));
   ASSERT_OK(GetMemTableRepFactoryFromString("prefix_hash:1000",
                                             &new_mem_factory));
-  ASSERT_EQ(std::string(new_mem_factory->Name()), "HashSkipListRepFactory");
+  ASSERT_STREQ(new_mem_factory->Name(), "HashSkipListRepFactory");
   ASSERT_NOK(GetMemTableRepFactoryFromString("prefix_hash:1000:invalid_opt",
                                              &new_mem_factory));
 
@@ -1170,6 +1171,99 @@ TEST_F(OptionsTest, GetMemTableRepFactoryFromString) {
 }
 #endif  // !ROCKSDB_LITE
 
+TEST_F(OptionsTest, MemTableRepFactoryCreateFromString) {
+  std::unique_ptr<MemTableRepFactory> new_mem_factory = nullptr;
+  ConfigOptions config_options;
+  config_options.ignore_unsupported_options = false;
+  config_options.ignore_unknown_options = false;
+
+  ASSERT_OK(MemTableRepFactory::CreateFromString(config_options, "skip_list",
+                                                 &new_mem_factory));
+  ASSERT_OK(MemTableRepFactory::CreateFromString(config_options, "skip_list:16",
+                                                 &new_mem_factory));
+  ASSERT_STREQ(new_mem_factory->Name(), "SkipListFactory");
+  ASSERT_TRUE(new_mem_factory->IsInstanceOf("skip_list"));
+  ASSERT_TRUE(new_mem_factory->IsInstanceOf("SkipListFactory"));
+  ASSERT_NOK(MemTableRepFactory::CreateFromString(
+      config_options, "skip_list:16:invalid_opt", &new_mem_factory));
+
+  ASSERT_NOK(MemTableRepFactory::CreateFromString(
+      config_options, "invalid_opt=10", &new_mem_factory));
+
+  // Test a reset
+  ASSERT_OK(MemTableRepFactory::CreateFromString(config_options, "",
+                                                 &new_mem_factory));
+  ASSERT_EQ(new_mem_factory, nullptr);
+  ASSERT_NOK(MemTableRepFactory::CreateFromString(
+      config_options, "invalid_opt=10", &new_mem_factory));
+
+#ifndef ROCKSDB_LITE
+  ASSERT_OK(MemTableRepFactory::CreateFromString(
+      config_options, "id=skip_list; lookahead=32", &new_mem_factory));
+  ASSERT_OK(MemTableRepFactory::CreateFromString(config_options, "prefix_hash",
+                                                 &new_mem_factory));
+  ASSERT_OK(MemTableRepFactory::CreateFromString(
+      config_options, "prefix_hash:1000", &new_mem_factory));
+  ASSERT_STREQ(new_mem_factory->Name(), "HashSkipListRepFactory");
+  ASSERT_TRUE(new_mem_factory->IsInstanceOf("prefix_hash"));
+  ASSERT_TRUE(new_mem_factory->IsInstanceOf("HashSkipListRepFactory"));
+  ASSERT_NOK(MemTableRepFactory::CreateFromString(
+      config_options, "prefix_hash:1000:invalid_opt", &new_mem_factory));
+  ASSERT_OK(MemTableRepFactory::CreateFromString(
+      config_options,
+      "id=prefix_hash; bucket_count=32; skiplist_height=64; "
+      "branching_factor=16",
+      &new_mem_factory));
+  ASSERT_NOK(MemTableRepFactory::CreateFromString(
+      config_options,
+      "id=prefix_hash; bucket_count=32; skiplist_height=64; "
+      "branching_factor=16; invalid=unknown",
+      &new_mem_factory));
+
+  ASSERT_OK(MemTableRepFactory::CreateFromString(
+      config_options, "hash_linkedlist", &new_mem_factory));
+  ASSERT_OK(MemTableRepFactory::CreateFromString(
+      config_options, "hash_linkedlist:1000", &new_mem_factory));
+  ASSERT_STREQ(new_mem_factory->Name(), "HashLinkListRepFactory");
+  ASSERT_TRUE(new_mem_factory->IsInstanceOf("hash_linkedlist"));
+  ASSERT_TRUE(new_mem_factory->IsInstanceOf("HashLinkListRepFactory"));
+  ASSERT_NOK(MemTableRepFactory::CreateFromString(
+      config_options, "hash_linkedlist:1000:invalid_opt", &new_mem_factory));
+  ASSERT_OK(MemTableRepFactory::CreateFromString(
+      config_options,
+      "id=hash_linkedlist; bucket_count=32; threshold=64; huge_page_size=16; "
+      "logging_threshold=12; log_when_flash=true",
+      &new_mem_factory));
+  ASSERT_NOK(MemTableRepFactory::CreateFromString(
+      config_options,
+      "id=hash_linkedlist; bucket_count=32; threshold=64; huge_page_size=16; "
+      "logging_threshold=12; log_when_flash=true; invalid=unknown",
+      &new_mem_factory));
+
+  ASSERT_OK(MemTableRepFactory::CreateFromString(config_options, "vector",
+                                                 &new_mem_factory));
+  ASSERT_OK(MemTableRepFactory::CreateFromString(config_options, "vector:1024",
+                                                 &new_mem_factory));
+  ASSERT_STREQ(new_mem_factory->Name(), "VectorRepFactory");
+  ASSERT_TRUE(new_mem_factory->IsInstanceOf("vector"));
+  ASSERT_TRUE(new_mem_factory->IsInstanceOf("VectorRepFactory"));
+  ASSERT_NOK(MemTableRepFactory::CreateFromString(
+      config_options, "vector:1024:invalid_opt", &new_mem_factory));
+  ASSERT_OK(MemTableRepFactory::CreateFromString(
+      config_options, "id=vector; count=42", &new_mem_factory));
+  ASSERT_NOK(MemTableRepFactory::CreateFromString(
+      config_options, "id=vector; invalid=unknown", &new_mem_factory));
+#endif  // ROCKSDB_LITE
+  ASSERT_NOK(MemTableRepFactory::CreateFromString(config_options, "cuckoo",
+                                                  &new_mem_factory));
+  // CuckooHash memtable is already removed.
+  ASSERT_NOK(MemTableRepFactory::CreateFromString(config_options, "cuckoo:1024",
+                                                  &new_mem_factory));
+
+  ASSERT_NOK(MemTableRepFactory::CreateFromString(config_options, "bad_factory",
+                                                  &new_mem_factory));
+}
+
 #ifndef ROCKSDB_LITE  // GetOptionsFromString is not supported in RocksDB Lite
 TEST_F(OptionsTest, GetOptionsFromStringTest) {
   Options base_options, new_options;
@@ -2454,7 +2548,7 @@ TEST_F(OptionsOldApiTest, GetColumnFamilyOptionsFromStringTest) {
             "memtable=skip_list:10;arena_block_size=1024",
             &new_cf_opt));
   ASSERT_TRUE(new_cf_opt.memtable_factory != nullptr);
-  ASSERT_EQ(std::string(new_cf_opt.memtable_factory->Name()), "SkipListFactory");
+  ASSERT_TRUE(new_cf_opt.memtable_factory->IsInstanceOf("SkipListFactory"));
 }
 
 TEST_F(OptionsOldApiTest, GetBlockBasedTableOptionsFromString) {
@@ -2650,6 +2744,14 @@ TEST_F(OptionsOldApiTest, GetPlainTableOptionsFromString) {
   ASSERT_TRUE(new_opt.full_scan_mode);
   ASSERT_TRUE(new_opt.store_index_in_file);
 
+  std::unordered_map<std::string, std::string> opt_map;
+  ASSERT_OK(StringToMap(
+      "user_key_len=55;bloom_bits_per_key=10;huge_page_tlb_size=8;", &opt_map));
+  ASSERT_OK(GetPlainTableOptionsFromMap(table_opt, opt_map, &new_opt));
+  ASSERT_EQ(new_opt.user_key_len, 55u);
+  ASSERT_EQ(new_opt.bloom_bits_per_key, 10);
+  ASSERT_EQ(new_opt.huge_page_tlb_size, 8);
+
   // unknown option
   ASSERT_NOK(GetPlainTableOptionsFromString(table_opt,
              "user_key_len=66;bloom_bits_per_key=20;hash_table_ratio=0.5;"

table/plain/plain_table_factory.cc

@@ -3,7 +3,6 @@
 // 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.
 
-#ifndef ROCKSDB_LITE
 #include "table/plain/plain_table_factory.h"
 
 #include <stdint.h>
@@ -11,15 +10,17 @@
 #include <memory>
 
 #include "db/dbformat.h"
-#include "options/configurable_helper.h"
 #include "port/port.h"
 #include "rocksdb/convenience.h"
+#include "rocksdb/utilities/customizable_util.h"
+#include "rocksdb/utilities/object_registry.h"
 #include "rocksdb/utilities/options_type.h"
 #include "table/plain/plain_table_builder.h"
 #include "table/plain/plain_table_reader.h"
 #include "util/string_util.h"
 
 namespace ROCKSDB_NAMESPACE {
+#ifndef ROCKSDB_LITE
 static std::unordered_map<std::string, OptionTypeInfo> plain_table_type_info = {
     {"user_key_len",
      {offsetof(struct PlainTableOptions, user_key_len), OptionType::kUInt32T,
@@ -151,73 +152,146 @@ Status GetPlainTableOptionsFromString(const ConfigOptions& config_options,
     return Status::InvalidArgument(s.getState());
   }
 }
+#endif  // ROCKSDB_LITE
 
+#ifndef ROCKSDB_LITE
+static int RegisterBuiltinMemTableRepFactory(ObjectLibrary& library,
+                                             const std::string& /*arg*/) {
+  // The MemTableRepFactory built-in classes will be either a class
+  // (VectorRepFactory) or a nickname (vector), followed optionally by ":#",
+  // where # is the "size" of the factory.
+  auto AsRegex = [](const std::string& name, const std::string& alt) {
+    std::string regex;
+    regex.append("(").append(name);
+    regex.append("|").append(alt).append(")(:[0-9]*)?");
+    return regex;
+  };
+
+  library.Register<MemTableRepFactory>(
+      AsRegex(VectorRepFactory::kClassName(), VectorRepFactory::kNickName()),
+      [](const std::string& uri, std::unique_ptr<MemTableRepFactory>* guard,
+         std::string* /*errmsg*/) {
+        auto colon = uri.find(":");
+        if (colon != std::string::npos) {
+          size_t count = ParseSizeT(uri.substr(colon + 1));
+          guard->reset(new VectorRepFactory(count));
+        } else {
+          guard->reset(new VectorRepFactory());
+        }
+        return guard->get();
+      });
+  library.Register<MemTableRepFactory>(
+      AsRegex(SkipListFactory::kClassName(), SkipListFactory::kNickName()),
+      [](const std::string& uri, std::unique_ptr<MemTableRepFactory>* guard,
+         std::string* /*errmsg*/) {
+        auto colon = uri.find(":");
+        if (colon != std::string::npos) {
+          size_t lookahead = ParseSizeT(uri.substr(colon + 1));
+          guard->reset(new SkipListFactory(lookahead));
+        } else {
+          guard->reset(new SkipListFactory());
+        }
+        return guard->get();
+      });
+  library.Register<MemTableRepFactory>(
+      AsRegex("HashLinkListRepFactory", "hash_linkedlist"),
+      [](const std::string& uri, std::unique_ptr<MemTableRepFactory>* guard,
+         std::string* /*errmsg*/) {
+        // Expecting format: hash_linkedlist:<hash_bucket_count>
+        auto colon = uri.find(":");
+        if (colon != std::string::npos) {
+          size_t hash_bucket_count = ParseSizeT(uri.substr(colon + 1));
+          guard->reset(NewHashLinkListRepFactory(hash_bucket_count));
+        } else {
+          guard->reset(NewHashLinkListRepFactory());
+        }
+        return guard->get();
+      });
+  library.Register<MemTableRepFactory>(
+      AsRegex("HashSkipListRepFactory", "prefix_hash"),
+      [](const std::string& uri, std::unique_ptr<MemTableRepFactory>* guard,
+         std::string* /*errmsg*/) {
+        // Expecting format: prefix_hash:<hash_bucket_count>
+        auto colon = uri.find(":");
+        if (colon != std::string::npos) {
+          size_t hash_bucket_count = ParseSizeT(uri.substr(colon + 1));
+          guard->reset(NewHashSkipListRepFactory(hash_bucket_count));
+        } else {
+          guard->reset(NewHashSkipListRepFactory());
+        }
+        return guard->get();
+      });
+  library.Register<MemTableRepFactory>(
+      "cuckoo",
+      [](const std::string& /*uri*/,
+         std::unique_ptr<MemTableRepFactory>* /*guard*/, std::string* errmsg) {
+        *errmsg = "cuckoo hash memtable is not supported anymore.";
+        return nullptr;
+      });
+
+  return 5;
+}
+#endif  // ROCKSDB_LITE
 Status GetMemTableRepFactoryFromString(
-    const std::string& opts_str,
+    const std::string& opts_str, std::unique_ptr<MemTableRepFactory>* result) {
-    std::unique_ptr<MemTableRepFactory>* new_mem_factory) {
+  ConfigOptions config_options;
-  std::vector<std::string> opts_list = StringSplit(opts_str, ':');
+  config_options.ignore_unsupported_options = false;
-  size_t len = opts_list.size();
+  config_options.ignore_unknown_options = false;
-
+  return MemTableRepFactory::CreateFromString(config_options, opts_str, result);
-  if (opts_list.empty() || opts_list.size() > 2) {
-    return Status::InvalidArgument("Can't parse memtable_factory option ",
-                                   opts_str);
 }
 
-  MemTableRepFactory* mem_factory = nullptr;
+Status MemTableRepFactory::CreateFromString(
-
+    const ConfigOptions& config_options, const std::string& value,
-  if (opts_list[0] == "skip_list" || opts_list[0] == "SkipListFactory") {
+    std::unique_ptr<MemTableRepFactory>* result) {
+#ifndef ROCKSDB_LITE
+  static std::once_flag once;
+  std::call_once(once, [&]() {
+    RegisterBuiltinMemTableRepFactory(*(ObjectLibrary::Default().get()), "");
+  });
+#endif  // ROCKSDB_LITE
+  std::string id;
+  std::unordered_map<std::string, std::string> opt_map;
+  Status status = Customizable::GetOptionsMap(config_options, result->get(),
+                                              value, &id, &opt_map);
+  if (!status.ok()) {  // GetOptionsMap failed
+    return status;
+  } else if (value.empty()) {
+    // No Id and no options.  Clear the object
+    result->reset();
+    return Status::OK();
+  } else if (id.empty()) {  // We have no Id but have options.  Not good
+    return Status::NotSupported("Cannot reset object ", id);
+  } else {
+#ifndef ROCKSDB_LITE
+    status = NewUniqueObject<MemTableRepFactory>(config_options, id, opt_map,
+                                                 result);
+#else
+    // To make it possible to configure the memtables in LITE mode, the ID
+    // is of the form <name>:<size>, where name is the name of the class and
+    // <size> is the length of the object (e.g. skip_list:10).
+    std::vector<std::string> opts_list = StringSplit(id, ':');
+    if (opts_list.empty() || opts_list.size() > 2 || !opt_map.empty()) {
+      status = Status::InvalidArgument("Can't parse memtable_factory option ",
+                                       value);
+    } else if (opts_list[0] == "skip_list" ||
+               opts_list[0] == SkipListFactory::kClassName()) {
       // Expecting format
       // skip_list:<lookahead>
-    if (2 == len) {
+      if (opts_list.size() == 2) {
         size_t lookahead = ParseSizeT(opts_list[1]);
-      mem_factory = new SkipListFactory(lookahead);
+        result->reset(new SkipListFactory(lookahead));
-    } else if (1 == len) {
-      mem_factory = new SkipListFactory();
-    }
-  } else if (opts_list[0] == "prefix_hash" ||
-             opts_list[0] == "HashSkipListRepFactory") {
-    // Expecting format
-    // prfix_hash:<hash_bucket_count>
-    if (2 == len) {
-      size_t hash_bucket_count = ParseSizeT(opts_list[1]);
-      mem_factory = NewHashSkipListRepFactory(hash_bucket_count);
-    } else if (1 == len) {
-      mem_factory = NewHashSkipListRepFactory();
-    }
-  } else if (opts_list[0] == "hash_linkedlist" ||
-             opts_list[0] == "HashLinkListRepFactory") {
-    // Expecting format
-    // hash_linkedlist:<hash_bucket_count>
-    if (2 == len) {
-      size_t hash_bucket_count = ParseSizeT(opts_list[1]);
-      mem_factory = NewHashLinkListRepFactory(hash_bucket_count);
-    } else if (1 == len) {
-      mem_factory = NewHashLinkListRepFactory();
-    }
-  } else if (opts_list[0] == "vector" || opts_list[0] == "VectorRepFactory") {
-    // Expecting format
-    // vector:<count>
-    if (2 == len) {
-      size_t count = ParseSizeT(opts_list[1]);
-      mem_factory = new VectorRepFactory(count);
-    } else if (1 == len) {
-      mem_factory = new VectorRepFactory();
-    }
-  } else if (opts_list[0] == "cuckoo") {
-    return Status::NotSupported(
-        "cuckoo hash memtable is not supported anymore.");
       } else {
-    return Status::InvalidArgument("Unrecognized memtable_factory option ",
+        result->reset(new SkipListFactory());
-                                   opts_str);
+      }
-  }
+    } else if (!config_options.ignore_unsupported_options) {
-
+      status = Status::NotSupported("Cannot load object in LITE mode ", id);
-  if (mem_factory != nullptr) {
+    }
-    new_mem_factory->reset(mem_factory);
+#endif  // ROCKSDB_LITE
-  }
+  }
-
+  return status;
-  return Status::OK();
 }
 
+#ifndef ROCKSDB_LITE
 Status GetPlainTableOptionsFromMap(
     const PlainTableOptions& table_options,
     const std::unordered_map<std::string, std::string>& opts_map,
@@ -259,5 +333,5 @@ const std::string PlainTablePropertyNames::kBloomVersion =
 const std::string PlainTablePropertyNames::kNumBloomBlocks =
     "rocksdb.plain.table.bloom.numblocks";
 
-}  // namespace ROCKSDB_NAMESPACE
 #endif  // ROCKSDB_LITE
+}  // namespace ROCKSDB_NAMESPACE

test_util/testutil.cc

@@ -601,6 +601,106 @@ Status CreateEnvFromSystem(const ConfigOptions& config_options, Env** result,
     return Status::OK();
   }
 }
+namespace {
+// A hacky skip list mem table that triggers flush after number of entries.
+class SpecialMemTableRep : public MemTableRep {
+ public:
+  explicit SpecialMemTableRep(Allocator* allocator, MemTableRep* memtable,
+                              int num_entries_flush)
+      : MemTableRep(allocator),
+        memtable_(memtable),
+        num_entries_flush_(num_entries_flush),
+        num_entries_(0) {}
+
+  virtual KeyHandle Allocate(const size_t len, char** buf) override {
+    return memtable_->Allocate(len, buf);
+  }
+
+  // Insert key into the list.
+  // REQUIRES: nothing that compares equal to key is currently in the list.
+  virtual void Insert(KeyHandle handle) override {
+    num_entries_++;
+    memtable_->Insert(handle);
+  }
+
+  void InsertConcurrently(KeyHandle handle) override {
+    num_entries_++;
+    memtable_->Insert(handle);
+  }
+
+  // Returns true iff an entry that compares equal to key is in the list.
+  virtual bool Contains(const char* key) const override {
+    return memtable_->Contains(key);
+  }
+
+  virtual size_t ApproximateMemoryUsage() override {
+    // Return a high memory usage when number of entries exceeds the threshold
+    // to trigger a flush.
+    return (num_entries_ < num_entries_flush_) ? 0 : 1024 * 1024 * 1024;
+  }
+
+  virtual void Get(const LookupKey& k, void* callback_args,
+                   bool (*callback_func)(void* arg,
+                                         const char* entry)) override {
+    memtable_->Get(k, callback_args, callback_func);
+  }
+
+  uint64_t ApproximateNumEntries(const Slice& start_ikey,
+                                 const Slice& end_ikey) override {
+    return memtable_->ApproximateNumEntries(start_ikey, end_ikey);
+  }
+
+  virtual MemTableRep::Iterator* GetIterator(Arena* arena = nullptr) override {
+    return memtable_->GetIterator(arena);
+  }
+
+  virtual ~SpecialMemTableRep() override {}
+
+ private:
+  std::unique_ptr<MemTableRep> memtable_;
+  int num_entries_flush_;
+  int num_entries_;
+};
+class SpecialSkipListFactory : public MemTableRepFactory {
+ public:
+  // After number of inserts exceeds `num_entries_flush` in a mem table, trigger
+  // flush.
+  explicit SpecialSkipListFactory(int num_entries_flush)
+      : num_entries_flush_(num_entries_flush) {}
+
+  using MemTableRepFactory::CreateMemTableRep;
+  virtual MemTableRep* CreateMemTableRep(
+      const MemTableRep::KeyComparator& compare, Allocator* allocator,
+      const SliceTransform* transform, Logger* /*logger*/) override {
+    return new SpecialMemTableRep(
+        allocator,
+        factory_.CreateMemTableRep(compare, allocator, transform, nullptr),
+        num_entries_flush_);
+  }
+  static const char* kClassName() { return "SpecialSkipListFactory"; }
+  virtual const char* Name() const override { return kClassName(); }
+  std::string GetId() const override {
+    std::string id = Name();
+    if (num_entries_flush_ > 0) {
+      id.append(":").append(ROCKSDB_NAMESPACE::ToString(num_entries_flush_));
+    }
+    return id;
+  }
+
+  bool IsInsertConcurrentlySupported() const override {
+    return factory_.IsInsertConcurrentlySupported();
+  }
+
+ private:
+  SkipListFactory factory_;
+  int num_entries_flush_;
+};
+}  // namespace
+
+MemTableRepFactory* NewSpecialSkipListFactory(int num_entries_per_flush) {
+  RegisterTestLibrary();
+  return new SpecialSkipListFactory(num_entries_per_flush);
+}
 
 #ifndef ROCKSDB_LITE
 // This method loads existing test classes into the ObjectRegistry
@@ -614,6 +714,19 @@ int RegisterTestObjects(ObjectLibrary& library, const std::string& /*arg*/) {
         static test::SimpleSuffixReverseComparator ssrc;
         return &ssrc;
       });
+  library.Register<MemTableRepFactory>(
+      std::string(SpecialSkipListFactory::kClassName()) + "(:[0-9]*)?",
+      [](const std::string& uri, std::unique_ptr<MemTableRepFactory>* guard,
+         std::string* /* errmsg */) {
+        auto colon = uri.find(":");
+        if (colon != std::string::npos) {
+          auto count = ParseInt(uri.substr(colon + 1));
+          guard->reset(new SpecialSkipListFactory(count));
+        } else {
+          guard->reset(new SpecialSkipListFactory(2));
+        }
+        return guard->get();
+      });
   library.Register<MergeOperator>(
       "Changling",
       [](const std::string& uri, std::unique_ptr<MergeOperator>* guard,
@@ -637,6 +750,19 @@ int RegisterTestObjects(ObjectLibrary& library, const std::string& /*arg*/) {
 
   return static_cast<int>(library.GetFactoryCount(&num_types));
 }
+
 #endif  // ROCKSDB_LITE
+
+void RegisterTestLibrary(const std::string& arg) {
+  static bool registered = false;
+  if (!registered) {
+    registered = true;
+#ifndef ROCKSDB_LITE
+    ObjectRegistry::Default()->AddLibrary("test", RegisterTestObjects, arg);
+#else
+    (void)arg;
+#endif  // ROCKSDB_LITE
+  }
+}
 }  // namespace test
 }  // namespace ROCKSDB_NAMESPACE

test_util/testutil.h

@@ -27,6 +27,7 @@
 
 namespace ROCKSDB_NAMESPACE {
 class FileSystem;
+class MemTableRepFactory;
 class ObjectLibrary;
 class Random;
 class SequentialFile;
@@ -853,6 +854,10 @@ class ChanglingCompactionFilterFactory : public CompactionFilterFactory {
   std::string name_;
 };
 
+// The factory for the hacky skip list mem table that triggers flush after
+// number of entries exceeds a threshold.
+extern MemTableRepFactory* NewSpecialSkipListFactory(int num_entries_per_flush);
+
 extern const Comparator* ComparatorWithU64Ts();
 
 CompressionType RandomCompressionType(Random* rnd);
@@ -901,5 +906,8 @@ Status CreateEnvFromSystem(const ConfigOptions& options, Env** result,
 // Registers the testutil classes with the ObjectLibrary
 int RegisterTestObjects(ObjectLibrary& library, const std::string& /*arg*/);
 #endif  // ROCKSDB_LITE
+
+// Register the testutil classes with the default ObjectRegistry/Library
+void RegisterTestLibrary(const std::string& arg = "");
 }  // namespace test
 }  // namespace ROCKSDB_NAMESPACE

tools/db_bench_tool.cc

@@ -1447,30 +1447,6 @@ DEFINE_int64(multiread_stride, 0,
              "Stride length for the keys in a MultiGet batch");
 DEFINE_bool(multiread_batched, false, "Use the new MultiGet API");
 
-enum RepFactory {
-  kSkipList,
-  kPrefixHash,
-  kVectorRep,
-  kHashLinkedList,
-};
-
-static enum RepFactory StringToRepFactory(const char* ctype) {
-  assert(ctype);
-
-  if (!strcasecmp(ctype, "skip_list"))
-    return kSkipList;
-  else if (!strcasecmp(ctype, "prefix_hash"))
-    return kPrefixHash;
-  else if (!strcasecmp(ctype, "vector"))
-    return kVectorRep;
-  else if (!strcasecmp(ctype, "hash_linkedlist"))
-    return kHashLinkedList;
-
-  fprintf(stdout, "Cannot parse memreptable %s\n", ctype);
-  return kSkipList;
-}
-
-static enum RepFactory FLAGS_rep_factory;
 DEFINE_string(memtablerep, "skip_list", "");
 DEFINE_int64(hash_bucket_count, 1024 * 1024, "hash bucket count");
 DEFINE_bool(use_plain_table, false, "if use plain table "
@@ -1534,8 +1510,33 @@ static const bool FLAGS_table_cache_numshardbits_dummy __attribute__((__unused__
                           &ValidateTableCacheNumshardbits);
 
 namespace ROCKSDB_NAMESPACE {
-
 namespace {
+static Status CreateMemTableRepFactory(
+    const ConfigOptions& config_options,
+    std::shared_ptr<MemTableRepFactory>* factory) {
+  Status s;
+  if (!strcasecmp(FLAGS_memtablerep.c_str(), SkipListFactory::kNickName())) {
+    factory->reset(new SkipListFactory(FLAGS_skip_list_lookahead));
+#ifndef ROCKSDB_LITE
+  } else if (!strcasecmp(FLAGS_memtablerep.c_str(), "prefix_hash")) {
+    factory->reset(NewHashSkipListRepFactory(FLAGS_hash_bucket_count));
+  } else if (!strcasecmp(FLAGS_memtablerep.c_str(),
+                         VectorRepFactory::kNickName())) {
+    factory->reset(new VectorRepFactory());
+  } else if (!strcasecmp(FLAGS_memtablerep.c_str(), "hash_linkedlist")) {
+    factory->reset(NewHashLinkListRepFactory(FLAGS_hash_bucket_count));
+#endif  // ROCKSDB_LITE
+  } else {
+    std::unique_ptr<MemTableRepFactory> unique;
+    s = MemTableRepFactory::CreateFromString(config_options, FLAGS_memtablerep,
+                                             &unique);
+    if (s.ok()) {
+      factory->reset(unique.release());
+    }
+  }
+  return s;
+}
+
 struct ReportFileOpCounters {
   std::atomic<int> open_counter_;
   std::atomic<int> delete_counter_;
@@ -2681,7 +2682,7 @@ class Benchmark {
                         compressed);
   }
 
-  void PrintHeader() {
+  void PrintHeader(const Options& options) {
     PrintEnvironment();
     fprintf(stdout,
             "Keys:       %d bytes each (+ %d bytes user-defined timestamp)\n",
@@ -2731,20 +2732,9 @@ class Benchmark {
     fprintf(stdout, "Compression: %s\n", compression.c_str());
     fprintf(stdout, "Compression sampling rate: %" PRId64 "\n",
             FLAGS_sample_for_compression);
-
+    if (options.memtable_factory != nullptr) {
-    switch (FLAGS_rep_factory) {
+      fprintf(stdout, "Memtablerep: %s\n",
-      case kPrefixHash:
+              options.memtable_factory->GetId().c_str());
-        fprintf(stdout, "Memtablerep: prefix_hash\n");
-        break;
-      case kSkipList:
-        fprintf(stdout, "Memtablerep: skip_list\n");
-        break;
-      case kVectorRep:
-        fprintf(stdout, "Memtablerep: vector\n");
-        break;
-      case kHashLinkedList:
-        fprintf(stdout, "Memtablerep: hash_linkedlist\n");
-        break;
     }
     fprintf(stdout, "Perf Level: %d\n", FLAGS_perf_level);
 
@@ -3209,7 +3199,7 @@ class Benchmark {
       ErrorExit();
     }
     Open(&open_options_);
-    PrintHeader();
+    PrintHeader(open_options_);
     std::stringstream benchmark_stream(FLAGS_benchmarks);
     std::string name;
     std::unique_ptr<ExpiredTimeFilter> filter;
@@ -3932,6 +3922,7 @@ class Benchmark {
     printf("Initializing RocksDB Options from command-line flags\n");
     Options& options = *opts;
     ConfigOptions config_options(options);
+    config_options.ignore_unsupported_options = false;
 
     assert(db_.db == nullptr);
 
@@ -4007,42 +3998,25 @@ class Benchmark {
         FLAGS_level_compaction_dynamic_level_bytes;
     options.max_bytes_for_level_multiplier =
         FLAGS_max_bytes_for_level_multiplier;
-    if ((FLAGS_prefix_size == 0) && (FLAGS_rep_factory == kPrefixHash ||
+    Status s =
-                                     FLAGS_rep_factory == kHashLinkedList)) {
+        CreateMemTableRepFactory(config_options, &options.memtable_factory);
+    if (!s.ok()) {
+      fprintf(stderr, "Could not create memtable factory: %s\n",
+              s.ToString().c_str());
+      exit(1);
+    } else if ((FLAGS_prefix_size == 0) &&
+               (options.memtable_factory->IsInstanceOf("prefix_hash") ||
+                options.memtable_factory->IsInstanceOf("hash_linkedlist"))) {
       fprintf(stderr, "prefix_size should be non-zero if PrefixHash or "
                       "HashLinkedList memtablerep is used\n");
       exit(1);
     }
-    switch (FLAGS_rep_factory) {
-      case kSkipList:
-        options.memtable_factory.reset(new SkipListFactory(
-            FLAGS_skip_list_lookahead));
-        break;
-#ifndef ROCKSDB_LITE
-      case kPrefixHash:
-        options.memtable_factory.reset(
-            NewHashSkipListRepFactory(FLAGS_hash_bucket_count));
-        break;
-      case kHashLinkedList:
-        options.memtable_factory.reset(NewHashLinkListRepFactory(
-            FLAGS_hash_bucket_count));
-        break;
-      case kVectorRep:
-        options.memtable_factory.reset(
-          new VectorRepFactory
-        );
-        break;
-#else
-      default:
-        fprintf(stderr, "Only skip list is supported in lite mode\n");
-        exit(1);
-#endif  // ROCKSDB_LITE
-    }
     if (FLAGS_use_plain_table) {
 #ifndef ROCKSDB_LITE
-      if (FLAGS_rep_factory != kPrefixHash &&
+      if (!options.memtable_factory->IsInstanceOf("prefix_hash") &&
-          FLAGS_rep_factory != kHashLinkedList) {
+          !options.memtable_factory->IsInstanceOf("hash_linkedlist")) {
-        fprintf(stderr, "Waring: plain table is used with skipList\n");
+        fprintf(stderr, "Warning: plain table is used with %s\n",
+                options.memtable_factory->Name());
       }
 
       int bloom_bits_per_key = FLAGS_bloom_bits;
@@ -4298,8 +4272,8 @@ class Benchmark {
 
     // merge operator options
     if (!FLAGS_merge_operator.empty()) {
-      Status s = MergeOperator::CreateFromString(
+      s = MergeOperator::CreateFromString(config_options, FLAGS_merge_operator,
-          config_options, FLAGS_merge_operator, &options.merge_operator);
+                                          &options.merge_operator);
       if (!s.ok()) {
         fprintf(stderr, "invalid merge operator[%s]: %s\n",
                 FLAGS_merge_operator.c_str(), s.ToString().c_str());
@@ -8148,8 +8122,6 @@ int db_bench_tool(int argc, char** argv) {
   FLAGS_value_size_distribution_type_e =
     StringToDistributionType(FLAGS_value_size_distribution_type.c_str());
 
-  FLAGS_rep_factory = StringToRepFactory(FLAGS_memtablerep.c_str());
-
   // Note options sanitization may increase thread pool sizes according to
   // max_background_flushes/max_background_compactions/max_background_jobs
   FLAGS_env->SetBackgroundThreads(FLAGS_num_high_pri_threads,