offload periodic work

db/db_impl/db_impl.cc

@@ -773,16 +773,17 @@ void DBImpl::PrintStatistics() {
 void DBImpl::StartPeriodicWorkScheduler() {
 #ifndef ROCKSDB_LITE
 
+  bool disable_scheduler =
+      immutable_db_options_.disable_periodic_work_scheduler;
 #ifndef NDEBUG
   // It only used by test to disable scheduler
-  bool disable_scheduler = false;
   TEST_SYNC_POINT_CALLBACK(
       "DBImpl::StartPeriodicWorkScheduler:DisableScheduler",
       &disable_scheduler);
+#endif  // !NDEBUG
   if (disable_scheduler) {
     return;
   }
-#endif  // !NDEBUG
 
   {
     InstrumentedMutexLock l(&mutex_);

db/db_impl/db_impl.h

@@ -1131,6 +1131,21 @@ class DBImpl : public DB {
   // flush LOG out of application buffer
   void FlushInfoLog();
 
+  Status DoPeriodicWork(PeriodicWorkType type) override {
+    switch (type) {
+      case PeriodicWorkType::kFlushInfoLog:
+        FlushInfoLog();
+        break;
+      case PeriodicWorkType::kDumpStats:
+        DumpStats();
+        break;
+      case PeriodicWorkType::kPersistStats:
+        PersistStats();
+        break;
+    }
+    return Status::OK();
+  }
+
   // Interface to block and signal the DB in case of stalling writes by
   // WriteBufferManager. Each DBImpl object contains ptr to WBMStallInterface.
   // When DB needs to be blocked or signalled by WriteBufferManager,

include/rocksdb/db.h

@@ -1823,6 +1823,15 @@ class DB {
     return Status::NotSupported("GetStatsHistory() is not implemented.");
   }
 
+  enum PeriodicWorkType {
+    kFlushInfoLog = 0,
+    kDumpStats = 2,
+    kPersistStats = 1,
+  };
+  virtual Status DoPeriodicWork(PeriodicWorkType type) {
+    return Status::NotSupported("DoPeriodicWork() is not implemented.");
+  }
+
 #ifndef ROCKSDB_LITE
   // Make the secondary instance catch up with the primary by tailing and
   // replaying the MANIFEST and WAL of the primary.

include/rocksdb/options.h

@@ -829,6 +829,10 @@ struct DBOptions {
   // NOT SUPPORTED ANYMORE -- this options is no longer used
   bool skip_log_error_on_recovery = false;
 
+  // Disable periodic work scheduler. User should manually run periodic work
+  // with `DB::DoPeriodicWork()`. Default: false
+  bool disable_periodic_work_scheduler = false;
+
   // if not zero, dump rocksdb.stats to LOG every stats_dump_period_sec
   //
   // Default: 600 (10 min)

options/db_options.cc

@@ -541,6 +541,10 @@ static std::unordered_map<std::string, OptionTypeInfo>
          OptionTypeInfo::Enum<CacheTier>(
              offsetof(struct ImmutableDBOptions, lowest_used_cache_tier),
              &cache_tier_string_map, OptionTypeFlags::kNone)},
+        {"disable_periodic_work_scheduler",
+         {offsetof(struct ImmutableDBOptions, disable_periodic_work_scheduler),
+          OptionType::kBoolean, OptionVerificationType::kNormal,
+          OptionTypeFlags::kNone}},
 };
 
 const std::string OptionsHelper::kDBOptionsName = "DBOptions";
@@ -741,7 +745,8 @@ ImmutableDBOptions::ImmutableDBOptions(const DBOptions& options)
       db_host_id(options.db_host_id),
       checksum_handoff_file_types(options.checksum_handoff_file_types),
       lowest_used_cache_tier(options.lowest_used_cache_tier),
-      compaction_service(options.compaction_service) {
+      compaction_service(options.compaction_service),
+      disable_periodic_work_scheduler(options.disable_periodic_work_scheduler) {
   stats = statistics.get();
   fs = env->GetFileSystem();
   if (env != nullptr) {
@@ -919,6 +924,10 @@ void ImmutableDBOptions::Dump(Logger* log) const {
                    allow_data_in_errors);
   ROCKS_LOG_HEADER(log, "            Options.db_host_id: %s",
                    db_host_id.c_str());
+  ROCKS_LOG_HEADER(log,
+                   "                       "
+                   "Options.disable_periodic_work_scheduler: %d",
+                   disable_periodic_work_scheduler);
 }
 
 bool ImmutableDBOptions::IsWalDirSameAsDBPath() const {

options/db_options.h

@@ -106,6 +106,7 @@ struct ImmutableDBOptions {
   Statistics* stats;
   Logger* logger;
   std::shared_ptr<CompactionService> compaction_service;
+  bool disable_periodic_work_scheduler;
 
   bool IsWalDirSameAsDBPath() const;
   bool IsWalDirSameAsDBPath(const std::string& path) const;

options/options_helper.cc

@@ -188,6 +188,8 @@ DBOptions BuildDBOptions(const ImmutableDBOptions& immutable_db_options,
   options.checksum_handoff_file_types =
       immutable_db_options.checksum_handoff_file_types;
   options.lowest_used_cache_tier = immutable_db_options.lowest_used_cache_tier;
+  options.disable_periodic_work_scheduler =
+      immutable_db_options.disable_periodic_work_scheduler;
   return options;
 }