diff --git a/backend/hdfs/object.go b/backend/hdfs/object.go
index d6d25297f..688e663ea 100644
--- a/backend/hdfs/object.go
+++ b/backend/hdfs/object.go
@@ -50,7 +50,10 @@ func (o *Object) SetModTime(ctx context.Context, modTime time.Time) error {
 	if err != nil {
 		return err
 	}
-	o.modTime = modTime
+	// Chtimes sets the modtime with second precision so truncate
+	// here too to keep the in-memory modtime identical to the one a
+	// fresh listing returns.
+	o.modTime = modTime.Truncate(time.Second)
 	return nil
 }