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Re: absurdly slow git-diff

From
Mike Hommey <mh@glandium.org>
Date
Nov 7, 2008, 21:28 UTC
Message-ID
<20081107212836.GA22717@glandium.org>
In-Reply-To
<20081107200126.GA20284@toroid.org>
On Sat, Nov 08, 2008 at 01:31:27AM +0530, Abhijit Menon-Sen wrote:
Show 9 quoted lines
> I have a 240k-line file, and I change one character on every sixth line.
> The resulting diff gives git serious indigestion:
> 
> $ git --version
> git version 1.6.0.3.640.g6331a
> $ mkdir a; cd a; git init
> Initialized empty Git repository in /home/ams/a/.git/
> $ cp ../1 .; git add 1; git commit -q -m 1
> $ cp ../2 1; git add 1; git commit -q -m 2

You don't need to go that far. You can stop at cp ../2 1 and run git diff from there.

All the time is spent in the two loops in xdiff/xprepare.c:xdl_cleanup_records, on line 400 and 412.

I'll leave the rest of the investigation to people actually knowing this code ;)

Mike
Previous: Abhijit Menon-SenNext: Linus Torvalds
Message 2 of 13 in “absurdly slow git-diff”
  1. Abhijit Menon-SenNov 7, 2008
  2. Mike HommeyNov 7, 2008
  3. Linus TorvaldsNov 7, 2008
  4. Davide LibenziNov 7, 2008
  5. Davide LibenziNov 7, 2008
  6. Linus TorvaldsNov 7, 2008
  7. Davide LibenziNov 7, 2008
  8. Linus TorvaldsNov 7, 2008
  9. Abhijit Menon-SenNov 8, 2008
  10. Junio C HamanoNov 8, 2008
  11. Junio C HamanoNov 8, 2008
  12. Davide LibenziNov 8, 2008
  13. Pierre HabouzitNov 8, 2008

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