From: Noam Postavsky <npostavs@gmail.com>
Date: Thu, 12 Jul 2018 00:13:25 +0000 (-0400)
Subject: Speed up smerge-refine-regions by avoiding fsync
X-Git-Tag: emacs-27.0.90~4685
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=01dbf2a347944497fdcf2ec156f4605020d7ba2a;p=emacs.git

Speed up smerge-refine-regions by avoiding fsync

* lisp/vc/smerge-mode.el (smerge-refine-regions): Bind
write-region-inhibit-fsync to t.  This was reported in
https://github.com/magit/magit/pull/2834 to give a noticable speedup.
---

diff --git a/lisp/vc/smerge-mode.el b/lisp/vc/smerge-mode.el
index cb51fbab8eb..ff41473435c 100644
--- a/lisp/vc/smerge-mode.el
+++ b/lisp/vc/smerge-mode.el
@@ -1075,9 +1075,10 @@ used to replace chars to try and eliminate some spurious differences."
           (if smerge-refine-weight-hack (make-hash-table :test #'equal))))
     (unless (markerp beg1) (setq beg1 (copy-marker beg1)))
     (unless (markerp beg2) (setq beg2 (copy-marker beg2)))
-    ;; Chop up regions into smaller elements and save into files.
-    (smerge--refine-chopup-region beg1 end1 file1 preproc)
-    (smerge--refine-chopup-region beg2 end2 file2 preproc)
+    (let ((write-region-inhibit-fsync t)) ; Don't fsync temp files (Bug#12747).
+      ;; Chop up regions into smaller elements and save into files.
+      (smerge--refine-chopup-region beg1 end1 file1 preproc)
+      (smerge--refine-chopup-region beg2 end2 file2 preproc))
 
     ;; Call diff on those files.
     (unwind-protect