diff --git a/weed/topology/volume_layout.go b/weed/topology/volume_layout.go
index b6044e29f..33c08e0a5 100644
--- a/weed/topology/volume_layout.go
+++ b/weed/topology/volume_layout.go
@@ -53,7 +53,7 @@ func (vl *VolumeLayout) RegisterVolume(v *storage.VolumeInfo, dn *DataNode) {
 		vl.vid2location[v.Id] = NewVolumeLocationList()
 	}
 	vl.vid2location[v.Id].Set(dn)
-	glog.V(4).Infof("volume %d added to %s len %s copy %d", v.Id, dn.Id(), vl.vid2location[v.Id].Length(), v.ReplicaPlacement.GetCopyCount())
+	glog.V(4).Infof("volume %d added to %s len %d copy %d", v.Id, dn.Id(), vl.vid2location[v.Id].Length(), v.ReplicaPlacement.GetCopyCount())
 	for _, dn := range vl.vid2location[v.Id].list {
 		if v_info, err := dn.GetVolumesById(v.Id); err == nil {
 			if v_info.ReadOnly {