From mboxrd@z Thu Jan  1 00:00:00 1970
From: Adrian Bunk <bunk@kernel.org>
Subject: git-revert is a memory hog
Date: Sun, 27 Jan 2008 19:27:48 +0200
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I'm not sure whether this is already known, but when recently working 
for some time from a computer with "only" 512 MB RAM I ran into the huge 
memory usage of git-revert when it tries to revert old commits.

Example (in Linus' kernel tree with git 1.5.3.8):

<--  snip  -->

$ git-revert d19fbe8a7
Auto-merged drivers/input/input.c
CONFLICT (content): Merge conflict in drivers/input/input.c
Auto-merged include/linux/input.h
CONFLICT (content): Merge conflict in include/linux/input.h
Automatic revert failed.  After resolving the conflicts,
mark the corrected paths with 'git add <paths>' and commit the result.
$ 

<--  snip  -->

In top you can see that this took > 800 MB of RAM !

I don't know how easy it would be to implement, but shouldn't git-revert 
be able to be as fast and less memory consuming as
  git-show d19fbe8a7 | patch -p1 -R
?

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed