dynamic setting of stats_dump_period_sec through SetDBOption()

Summary:
Resolved the following issue: https://github.com/facebook/rocksdb/issues/1930
Closes https://github.com/facebook/rocksdb/pull/2004

Differential Revision: D4736764

Pulled By: yiwu-arbug

fbshipit-source-id: 64fe0b7

HISTORY.md

@@ -1,5 +1,7 @@
 # Rocksdb Change Log
 ## Unreleased
+### Public API Change
+* Support dynamically change `stats_dump_period_sec` option via SetDBOptions().
 
 ## 5.3.0 (03/08/2017)
 ### Public API Change

db/db_impl.cc

@@ -618,12 +618,15 @@ static void DumpMallocStats(std::string* stats) {
 #endif  // !ROCKSDB_LITE
 
 void DBImpl::MaybeDumpStats() {
-  if (immutable_db_options_.stats_dump_period_sec == 0) return;
+  mutex_.Lock();
+  unsigned int stats_dump_period_sec =
+      mutable_db_options_.stats_dump_period_sec;
+  mutex_.Unlock();
+  if (stats_dump_period_sec == 0) return;
 
   const uint64_t now_micros = env_->NowMicros();
 
-  if (last_stats_dump_time_microsec_ +
-          immutable_db_options_.stats_dump_period_sec * 1000000 <=
+  if (last_stats_dump_time_microsec_ + stats_dump_period_sec * 1000000 <=
       now_micros) {
     // Multiple threads could race in here simultaneously.
     // However, the last one will update last_stats_dump_time_microsec_

db/db_options_test.cc

@@ -326,6 +326,22 @@ TEST_F(DBOptionsTest, MaxTotalWalSizeChange) {
   }
 }
 
+TEST_F(DBOptionsTest, SetStatsDumpPeriodSec) {
+  Options options;
+  options.create_if_missing = true;
+  options.stats_dump_period_sec = 5;
+  options.env = env_;
+  Reopen(options);
+  ASSERT_EQ(5, dbfull()->GetDBOptions().stats_dump_period_sec);
+
+  for (int i = 0; i < 20; i++) {
+    int num = rand() % 5000 + 1;
+    ASSERT_OK(dbfull()->SetDBOptions(
+        {{"stats_dump_period_sec", std::to_string(num)}}));
+    ASSERT_EQ(num, dbfull()->GetDBOptions().stats_dump_period_sec);
+  }
+}
+
 static void assert_candidate_files_empty(DBImpl* dbfull, const bool empty) {
   dbfull->TEST_LockMutex();
   JobContext job_context(0);

java/src/main/java/org/rocksdb/DBOptionsInterface.java

@@ -715,7 +715,7 @@ public interface DBOptionsInterface {
 
   /**
    * if not zero, dump rocksdb.stats to LOG every stats_dump_period_sec
-   * Default: 3600 (1 hour)
+   * Default: 600 (10 minutes)
    *
    * @param statsDumpPeriodSec time interval in seconds.
    * @return the instance of the current Object.
@@ -724,7 +724,7 @@ public interface DBOptionsInterface {
 
   /**
    * If not zero, dump rocksdb.stats to LOG every stats_dump_period_sec
-   * Default: 3600 (1 hour)
+   * Default: 600 (10 minutes)
    *
    * @return time interval in seconds.
    */

util/db_options.cc

@@ -56,7 +56,6 @@ ImmutableDBOptions::ImmutableDBOptions(const DBOptions& options)
       use_direct_writes(options.use_direct_writes),
       allow_fallocate(options.allow_fallocate),
       is_fd_close_on_exec(options.is_fd_close_on_exec),
-      stats_dump_period_sec(options.stats_dump_period_sec),
       advise_random_on_open(options.advise_random_on_open),
       db_write_buffer_size(options.db_write_buffer_size),
       write_buffer_manager(options.write_buffer_manager),
@@ -154,8 +153,6 @@ void ImmutableDBOptions::Dump(Logger* log) const {
       manifest_preallocation_size);
   ROCKS_LOG_HEADER(log, "                    Options.is_fd_close_on_exec: %d",
                    is_fd_close_on_exec);
-  ROCKS_LOG_HEADER(log, "                  Options.stats_dump_period_sec: %u",
-                   stats_dump_period_sec);
   ROCKS_LOG_HEADER(log, "                  Options.advise_random_on_open: %d",
                    advise_random_on_open);
   ROCKS_LOG_HEADER(
@@ -223,7 +220,8 @@ MutableDBOptions::MutableDBOptions()
       avoid_flush_during_shutdown(false),
       delayed_write_rate(2 * 1024U * 1024U),
       max_total_wal_size(0),
-      delete_obsolete_files_period_micros(6ULL * 60 * 60 * 1000000) {}
+      delete_obsolete_files_period_micros(6ULL * 60 * 60 * 1000000),
+      stats_dump_period_sec(600) {}
 
 MutableDBOptions::MutableDBOptions(const DBOptions& options)
     : base_background_compactions(options.base_background_compactions),
@@ -232,7 +230,8 @@ MutableDBOptions::MutableDBOptions(const DBOptions& options)
       delayed_write_rate(options.delayed_write_rate),
       max_total_wal_size(options.max_total_wal_size),
       delete_obsolete_files_period_micros(
-          options.delete_obsolete_files_period_micros) {}
+          options.delete_obsolete_files_period_micros),
+      stats_dump_period_sec(options.stats_dump_period_sec) {}
 
 void MutableDBOptions::Dump(Logger* log) const {
   ROCKS_LOG_HEADER(log, "            Options.base_background_compactions: %d",
@@ -248,6 +247,8 @@ void MutableDBOptions::Dump(Logger* log) const {
   ROCKS_LOG_HEADER(
       log, "            Options.delete_obsolete_files_period_micros: %" PRIu64,
       delete_obsolete_files_period_micros);
+  ROCKS_LOG_HEADER(log, "                  Options.stats_dump_period_sec: %u",
+                   stats_dump_period_sec);
 }
 
 }  // namespace rocksdb

util/db_options.h

@@ -51,7 +51,6 @@ struct ImmutableDBOptions {
   bool use_direct_writes;
   bool allow_fallocate;
   bool is_fd_close_on_exec;
-  unsigned int stats_dump_period_sec;
   bool advise_random_on_open;
   size_t db_write_buffer_size;
   std::shared_ptr<WriteBufferManager> write_buffer_manager;
@@ -94,6 +93,7 @@ struct MutableDBOptions {
   uint64_t delayed_write_rate;
   uint64_t max_total_wal_size;
   uint64_t delete_obsolete_files_period_micros;
+  unsigned int stats_dump_period_sec;
 };
 
 }  // namespace rocksdb

util/options_helper.cc

@@ -76,7 +76,7 @@ DBOptions BuildDBOptions(const ImmutableDBOptions& immutable_db_options,
   options.use_direct_writes = immutable_db_options.use_direct_writes;
   options.allow_fallocate = immutable_db_options.allow_fallocate;
   options.is_fd_close_on_exec = immutable_db_options.is_fd_close_on_exec;
-  options.stats_dump_period_sec = immutable_db_options.stats_dump_period_sec;
+  options.stats_dump_period_sec = mutable_db_options.stats_dump_period_sec;
   options.advise_random_on_open = immutable_db_options.advise_random_on_open;
   options.db_write_buffer_size = immutable_db_options.db_write_buffer_size;
   options.write_buffer_manager = immutable_db_options.write_buffer_manager;

util/options_helper.h

@@ -330,7 +330,8 @@ static std::unordered_map<std::string, OptionTypeInfo> db_options_type_info = {
       OptionVerificationType::kNormal, false, 0}},
     {"stats_dump_period_sec",
      {offsetof(struct DBOptions, stats_dump_period_sec), OptionType::kUInt,
-      OptionVerificationType::kNormal, false, 0}},
+      OptionVerificationType::kNormal, true,
+      offsetof(struct MutableDBOptions, stats_dump_period_sec)}},
     {"fail_if_options_file_error",
      {offsetof(struct DBOptions, fail_if_options_file_error),
       OptionType::kBoolean, OptionVerificationType::kNormal, false, 0}},