diff --git a/metric/metric.go b/metric/metric.go
index c520214..82b4cf3 100644
--- a/metric/metric.go
+++ b/metric/metric.go
@@ -85,8 +85,15 @@ func (mw *metric_int64) Add(inc int64) {
 }
 
 func (mc *metricCollection) metricWriter() {
+	defer func() {
+		r := recover()
+		if r != nil {
+			logger.Error(r)
+		}
+	}()
+
 	// head + metric_key_size + 8byte + tail + cr = 19
-	var buff [20]byte
+	var buff [19]byte
 	buff[0] = METRIC_HEAD_INLINE
 	buff[17] = METRIC_TAIL_INLINE
 	buff[18] = '\n'