Add EventLogging option

db.go

@@ -270,13 +270,18 @@ func Open(opt Options) (db *DB, err error) {
 		}
 	}()
 
+	elog := noEventLog
+	if opt.EventLogging {
+		elog = trace.NewEventLog("Badger", "DB")
+	}
+
 	db = &DB{
 		imm:           make([]*skl.Skiplist, 0, opt.NumMemtables),
 		flushChan:     make(chan flushTask, opt.NumMemtables),
 		writeCh:       make(chan *request, kvWriteChCapacity),
 		opt:           opt,
 		manifest:      manifestFile,
-		elog:          trace.NewEventLog("Badger", "DB"),
+		elog:          elog,
 		dirLockGuard:  dirLockGuard,
 		valueDirGuard: valueDirLockGuard,
 		orc:           newOracle(opt),

nil_event_log.go

@@ -0,0 +1,15 @@
+package badger
+
+import "golang.org/x/net/trace"
+
+var (
+	noEventLog trace.EventLog = nilEventLog{}
+)
+
+type nilEventLog struct{}
+
+func (nel nilEventLog) Printf(format string, a ...interface{}) {}
+
+func (nel nilEventLog) Errorf(format string, a ...interface{}) {}
+
+func (nel nilEventLog) Finish() {}

options.go

@@ -44,6 +44,7 @@ type Options struct {
 	ReadOnly            bool
 	Truncate            bool
 	Logger              Logger
+	EventLogging        bool
 
 	// Fine tuning options.
 
@@ -114,6 +115,7 @@ func DefaultOptions(path string) Options {
 		ValueThreshold:     32,
 		Truncate:           false,
 		Logger:             defaultLogger,
+		EventLogging:       true,
 		LogRotatesToFlush:  2,
 	}
 }
@@ -237,6 +239,16 @@ func (opt Options) WithLogger(val Logger) Options {
 	return opt
 }
 
+// WithEventLogging returns a new Options value with EventLogging set to the given value.
+//
+// EventLogging provides a way to enable or disable trace.EventLog logging.
+//
+// The default value of EventLogging is true.
+func (opt Options) WithEventLogging(enabled bool) Options {
+	opt.EventLogging = enabled
+	return opt
+}
+
 // WithMaxTableSize returns a new Options value with MaxTableSize set to the given value.
 //
 // MaxTableSize sets the maximum size in bytes for each LSM table or file.