Re: pack-object poor performance (with large number of objects?)

From: Piotr Krukowiecki <piotr.krukowiecki@gmail.com>
Date: Oct 4, 2011, 13:21 UTC
Message-ID: <CAA01Csp2rouKk4jvCH0Wu+0gc3+cvyH__d-yw8EHEkeZhRpX1Q@mail.gmail.com>
In-Reply-To: <20111004124502.GB30162@sigill.intra.peff.net>

On Tue, Oct 4, 2011 at 2:45 PM, Jeff King <peff@peff.net> wrote:

Show 12 quoted lines

> On Tue, Oct 04, 2011 at 02:22:55PM +0200, Piotr Krukowiecki wrote:
>
>> > So my guess is that it is simply taking an enormous amount of disk
>> > space, and git is mostly waiting on the disk to read in files. What does
>> > "du -sh .git/objects" say?
>>
>> It isn't that big - it's 11G.
>> .git/objects/pack/ is 666MB currently.
>
> But you have 4G of RAM, no? So depending on the access patterns, you are
> thrashing your disk cache and always pulling each object straight from
> disk.

I have 4GB ram + 4GB swap. Is it possible the RAM is the problem if I always have free RAM left and my swap is almost not used? For example at the moment repack finished counting objects ("Counting objects: 1742200, done."):

$ free -m
             total       used       free     shared    buffers     cached
Mem:          3960       3814        146          0        441        215
-/+ buffers/cache:       3157        803
Swap:         6143        694       5449

$ ps auxwwww | grep git pkruk 13541 0.0 0.0 15704 716 pts/2 S+ 13:19 0:00 git repack -a -d -f pkruk 13542 0.0 0.0 4220 540 pts/2 S+ 13:19 0:00 /bin/sh /usr/local/stow/git-master/libexec/git-core/git-repack -a -d -f pkruk 13556 3.9 9.8 1143628 401232 pts/2 DN+ 13:19 4:25 git pack-objects --keep-true-parents --honor-pack-keep --non-empty --all --reflog --no-reuse-delta --delta-base-offset /home/pkruk/dv/devel1_git_repos/.git/objects/pack/.tmp-13542-pack

I have updated to 1.7.7 btw.

-- 
Piotr Krukowiecki