diff --git a/weed/util/log_buffer/log_buffer.go b/weed/util/log_buffer/log_buffer.go
index fb1f8dc2f..8683dfffc 100644
--- a/weed/util/log_buffer/log_buffer.go
+++ b/weed/util/log_buffer/log_buffer.go
@@ -75,6 +75,24 @@ func (logBuffer *LogBuffer) AddToBuffer(message *mq_pb.DataMessage) {
 
 func (logBuffer *LogBuffer) AddDataToBuffer(partitionKey, data []byte, processingTsNs int64) {
 
+	// PERFORMANCE OPTIMIZATION: Pre-process expensive operations OUTSIDE the lock
+	var ts time.Time
+	if processingTsNs == 0 {
+		ts = time.Now()
+		processingTsNs = ts.UnixNano()
+	} else {
+		ts = time.Unix(0, processingTsNs)
+	}
+
+	logEntry := &filer_pb.LogEntry{
+		TsNs:             processingTsNs, // Will be updated if needed
+		PartitionKeyHash: util.HashToInt32(partitionKey),
+		Data:             data,
+		Key:              partitionKey,
+	}
+
+	logEntryData, _ := proto.Marshal(logEntry)
+
 	var toFlush *dataToFlush
 	logBuffer.Lock()
 	defer func() {
@@ -87,28 +105,16 @@ func (logBuffer *LogBuffer) AddDataToBuffer(partitionKey, data []byte, processin
 		}
 	}()
 
-	// need to put the timestamp inside the lock
-	var ts time.Time
-	if processingTsNs == 0 {
-		ts = time.Now()
-		processingTsNs = ts.UnixNano()
-	} else {
-		ts = time.Unix(0, processingTsNs)
-	}
+	// Handle timestamp collision inside lock (rare case)
 	if logBuffer.LastTsNs.Load() >= processingTsNs {
-		// this is unlikely to happen, but just in case
 		processingTsNs = logBuffer.LastTsNs.Add(1)
 		ts = time.Unix(0, processingTsNs)
+		// Re-marshal with corrected timestamp
+		logEntry.TsNs = processingTsNs
+		logEntryData, _ = proto.Marshal(logEntry)
+	} else {
+		logBuffer.LastTsNs.Store(processingTsNs)
 	}
-	logBuffer.LastTsNs.Store(processingTsNs)
-	logEntry := &filer_pb.LogEntry{
-		TsNs:             processingTsNs,
-		PartitionKeyHash: util.HashToInt32(partitionKey),
-		Data:             data,
-		Key:              partitionKey,
-	}
-
-	logEntryData, _ := proto.Marshal(logEntry)
 
 	size := len(logEntryData)