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cmd/kava/opendb/opendb_rocksdb.go

@@ -43,7 +43,9 @@ const (
 
 	defaultColumnFamilyName = "default"
 
-	enableRocksdbMetricsOptName = "enable_rocksdb_metrics"
+	enableMetricsOptName             = "enable_rocksdb_metrics"
+	reportMetricsIntervalSecsOptName = "report_rocksdb_metrics_interval_secs"
+	defaultReportMetricsIntervalSecs = 15
 
 	maxOpenFilesDBOptName          = "max_open_files"
 	maxFileOpeningThreadsDBOptName = "max_file_opening_threads"
@@ -71,9 +73,8 @@ func openRocksdb(dir string, appOpts types.AppOptions) (dbm.DB, error) {
 	// customize rocksdb options
 	dbOpts = overrideDBOpts(dbOpts, appOpts)
 	cfOpts = overrideCFOpts(cfOpts, appOpts)
-	enableMetrics := cast.ToBool(appOpts.Get(enableRocksdbMetricsOptName))
 
-	return newRocksDBWithOptions("application", dir, dbOpts, cfOpts, enableMetrics)
+	return newRocksDBWithOptions("application", dir, dbOpts, cfOpts, appOpts)
 }
 
 // loadLatestOptions loads and returns database and column family options
@@ -132,14 +133,21 @@ func overrideCFOpts(cfOpts *grocksdb.Options, appOpts types.AppOptions) *grocksd
 
 // newRocksDBWithOptions opens rocksdb with provided database and column family options
 // newRocksDBWithOptions expects that db has only one column family named default
-func newRocksDBWithOptions(name string, dir string, dbOpts, cfOpts *grocksdb.Options, enableMetrics bool) (*dbm.RocksDB, error) {
+func newRocksDBWithOptions(name string, dir string, dbOpts, cfOpts *grocksdb.Options, appOpts types.AppOptions) (*dbm.RocksDB, error) {
+	enableMetrics := cast.ToBool(appOpts.Get(enableMetricsOptName))
+	reportMetricsIntervalSecs := cast.ToInt64(appOpts.Get(reportMetricsIntervalSecsOptName))
+	if reportMetricsIntervalSecs == 0 {
+		reportMetricsIntervalSecs = defaultReportMetricsIntervalSecs
+	}
+
 	dbPath := filepath.Join(dir, name+".db")
 
 	// Ensure path exists
 	if err := os.MkdirAll(dbPath, 0755); err != nil {
 		return nil, fmt.Errorf("failed to create db path: %w", err)
 	}
 
+	// EnableStatistics adds overhead so shouldn't be enabled in production
 	if enableMetrics {
 		dbOpts.EnableStatistics()
 	}
@@ -151,7 +159,7 @@ func newRocksDBWithOptions(name string, dir string, dbOpts, cfOpts *grocksdb.Opt
 
 	if enableMetrics {
 		registerMetrics()
-		go reportMetrics(db)
+		go reportMetrics(db, time.Second*time.Duration(reportMetricsIntervalSecs))
 	}
 
 	ro := grocksdb.NewDefaultReadOptions()
@@ -183,8 +191,10 @@ func newDefaultOptions() *grocksdb.Options {
 	return opts
 }
 
-func reportMetrics(db *grocksdb.DB) {
-	ticker := time.NewTicker(time.Second * 15)
+// reportMetrics periodically requests stats from rocksdb and reports to prometheus
+// NOTE: should be launched as a goroutine
+func reportMetrics(db *grocksdb.DB, interval time.Duration) {
+	ticker := time.NewTicker(interval)
 	for {
 		select {
 		case <-ticker.C:
@@ -198,6 +208,7 @@ func reportMetrics(db *grocksdb.DB) {
 	}
 }
 
+// getPropsAndStats gets statistics from rocksdb
 func getPropsAndStats(db *grocksdb.DB) (*properties, *stats, error) {
 	propsLoader := newPropsLoader(db)
 	props, err := propsLoader.load()