diff --git a/weed/server/volume_grpc_copy.go b/weed/server/volume_grpc_copy.go
index 5f59f7c23..92fe0a1be 100644
--- a/weed/server/volume_grpc_copy.go
+++ b/weed/server/volume_grpc_copy.go
@@ -147,7 +147,7 @@ func (vs *VolumeServer) VolumeCopy(req *volume_server_pb.VolumeCopyRequest, stre
 			os.Chtimes(indexBaseFileName+".idx", time.Unix(0, modifiedTsNs), time.Unix(0, modifiedTsNs))
 		}
 
-		if modifiedTsNs, err = vs.doCopyFileWithThrottler(client, false, req.Collection, req.VolumeId, volFileInfoResp.CompactionRevision, volFileInfoResp.DatFileSize, dataBaseFileName, ".vif", false, true, nil, throttler); err != nil {
+		if modifiedTsNs, err = vs.doCopyFileWithThrottler(client, false, req.Collection, req.VolumeId, volFileInfoResp.CompactionRevision, 1024*1024, dataBaseFileName, ".vif", false, true, nil, throttler); err != nil {
 			return err
 		}
 		if modifiedTsNs > 0 {