Re: Poor performance of git describe in big repos

From: Alex Bennée <kernel-hacker@bennee.com>
Date: May 30, 2013, 13:16 UTC
Message-ID: <CAJ-05NOyQu7pfY7jwKTJ2ZS_h9pBtnyeMAxJVzjC7R0kVoLUBw@mail.gmail.com>
In-Reply-To: <20130530114808.GD17475@serenity.lan>

> You may find that performance improves if you repack with "git gc

--aggressive".

It seems that increases the time to get to where it wants to:

14:12 ajb@sloy/x86_64 [work.git] >time /usr/bin/git --no-pager
describe --long --tags --debug
searching to describe HEAD
 lightweight       10 ajb-build-test-5224
 lightweight       41 ajb-build-test-5222
 annotated        146 vnms-2-1-36-32
 annotated        155 vnms-2-1-36-31
 annotated        174 vnms-2-1-36-30
 annotated        183 vnms-2-1-36-29
 lightweight      188 vnms-2-1-36-28
 annotated        193 vnms-2-1-36-27
 annotated        206 vnms-2-1-36-26
 annotated        215 vectastar-4-2-83-5
traversed 223 commits
more than 10 tags found; listed 10 most recent
gave up search at 2b69df72d47be8440e3ce4cee91b9b7ceaf8b77c
ajb-build-test-5224-10-gfa296e6

real 0m14.658s user 0m12.845s sys 0m1.776s

On 30 May 2013 12:48, John Keeping <john@keeping.me.uk> wrote:

Show 10 quoted lines

> On Thu, May 30, 2013 at 11:38:32AM +0100, Alex Bennée wrote:
>> One factor might be the size of my repo (.git is around 2.4G). Could
>> this just be due to computational cost of searching through large
>> packs to walk the commit chain? Is there any way to make this easier
>> for git to do?
>
> What does "git count-objects -v" say for your repository?
>
> You may find that performance improves if you repack with "git gc
> --aggressive".

-- 
Alex, homepage: http://www.bennee.com/~alex/