updated for version 7.0185
diff --git a/src/diff.c b/src/diff.c
index 1a382e3..b095854 100644
--- a/src/diff.c
+++ b/src/diff.c
@@ -441,9 +441,10 @@
     }
     diff_redraw(TRUE);
 
-    /* Recompute the scroll binding, may remove or add filler lines (e.g.,
-     * when adding lines above w_topline). */
-    check_scrollbind((linenr_T)0, 0L);
+    /* Need to recompute the scroll binding, may remove or add filler lines
+     * (e.g., when adding lines above w_topline). But it's slow when making
+     * many changes, postpone until redrawing. */
+    diff_need_scrollbind = TRUE;
 }
 
 /*