From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ramkumar Ramachandra <artagnon@gmail.com>
Subject: Re: Poor performance of git describe in big repos
Date: Thu, 30 May 2013 17:03:27 +0530
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Alex Benn=C3=A9e wrote:
>>time /usr/bin/git --no-pager
> traversed 223 commits
>
> real    0m4.817s
> user    0m4.320s
> sys     0m0.464s

I'm quite clueless about why it is taking this long: I think it's IO
because there's nothing to compute?  I really can't trace anything
unless you can reproduce it on a public repository.  On linux.git with
my rotating hard disk:

$ time git describe --debug --long --tags HEAD~10000
searching to describe HEAD~10000
 annotated       5445 v2.6.33
 annotated       5660 v2.6.33-rc8
 annotated       5884 v2.6.33-rc7
 annotated       6140 v2.6.33-rc6
 annotated       6467 v2.6.33-rc5
 annotated       6999 v2.6.33-rc4
 annotated       7430 v2.6.33-rc3
 annotated       7746 v2.6.33-rc2
 annotated       8212 v2.6.33-rc1
 annotated      13854 v2.6.32
traversed 18895 commits
more than 10 tags found; listed 10 most recent
gave up search at 648f4e3e50c4793d9dbf9a09afa193631f76fa26
v2.6.33-5445-ge7c84ee

real    0m0.509s
user    0m0.470s
sys     0m0.037s

18k+ commits traversed in half a second here, so I really don't know
what is going on.