diff --git a/weed/glog/glog.go b/weed/glog/glog.go
index 7ee718e30..2eaa9d2be 100644
--- a/weed/glog/glog.go
+++ b/weed/glog/glog.go
@@ -576,8 +576,8 @@ func (l *loggingT) formatHeader(s severity, file string, line int) *buffer {
 	buf.twoDigits(12, second)
 	buf.tmp[14] = '.'
 	buf.nDigits(6, 15, now.Nanosecond()/1000, '0')
-	buf.tmp[20] = ' '
-	buf.Write(buf.tmp[:21])
+	buf.tmp[21] = ' '
+	buf.Write(buf.tmp[:22])
 	buf.WriteString(file)
 	buf.tmp[0] = ':'
 	n := buf.someDigits(1, line)