From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ross Lagerwall <rosslagerwall@gmail.com>
Subject: Re: git grep performance regression
Date: Tue, 15 Jan 2013 07:36:28 +0000
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References: <20130114223800.GA12708@hobo.wolfson.cam.ac.uk>
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To: Duy Nguyen <pclouds@gmail.com>
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On Tue, Jan 15, 2013 at 11:38:32AM +0700, Duy Nguyen wrote:
> dirlen is not expected to include the trailing slash, but
> find_basename() does that. It messes up with the path filters for
> push/pop in the next code. This brings grep performance closely back
> to before for me. Ross, can you check (patch could be whitespace
> damaged by gmail)?
> 

Yes, that did seem to bring back the performance to the old level.

I noticed that before the patch, the strace output was something like
this:
open("tools/vm/.gitattributes", O_RDONLY) = -1 ENOENT
open("tools/vm//.gitattributes", O_RDONLY) = -1 ENOENT
open("tools/vm//.gitattributes", O_RDONLY) = -1 ENOENT
open("tools/vm//.gitattributes", O_RDONLY) = -1 ENOENT
open("usr/.gitattributes", O_RDONLY)    = -1 ENOENT
open("usr//.gitattributes", O_RDONLY)   = -1 ENOENT
open("usr//.gitattributes", O_RDONLY)   = -1 ENOENT
open("usr//.gitattributes", O_RDONLY)   = -1 ENOENT
open("usr//.gitattributes", O_RDONLY)   = -1 ENOENT
open("usr//.gitattributes", O_RDONLY)   = -1 ENOENT

(and yes, the whitespace was damaged by Gmail!)

Regards
-- 
Ross Lagerwall