Re: 'git gc --aggressive' effectively unusable

From: Michael Witten <mfwitten@gmail.com>
Date: Apr 3, 2010, 23:42 UTC
Message-ID: <j2pb4087cc51004031642qa9444506s8d0d34e57e541953@mail.gmail.com>
In-Reply-To: <201004040123.06877.elendil@planet.nl>

On Sat, Apr 3, 2010 at 17:23, Frans Pop <elendil@planet.nl> wrote:

Show 13 quoted lines

> On Saturday 03 April 2010, Michael Witten wrote:
>> On Fri, Apr 2, 2010 at 16:05, Frans Pop <elendil@planet.nl> wrote:
>> > I haven't had the patience to let it finish
> ...
> I've tried it today on my linux-2.6 repo as well and the same thing
> happened. At first the progress is not fast but reasonable. When it gets
> to about 45% percent it starts slowing down a lot: from ~1500 objects per
> update of the counters to ~300 objects per update. And who knows what
> the progress is going to be when it reaches 70% or 90%: 10 per update?
>
> With a total of over 2 milion objects in the repository such a low speed is
> simply not going to work, ever. So I maintain that it is effectively
> unusable.

Well, all I can do is quote myself:

    Last time I used this option (on Linus's Linux repo),
    I let the algorithm do its thing for a couple of hours.
    Maybe the efficiency could be vastly improved, but
    it does finish if you let it.

On Fri, Apr 2, 2010 at 16:12, Frans Pop <elendil@planet.nl> wrote:

> I'm seeing this with both git 1.6.6.1 and 1.7.0.3 on the same repo.

I think I must have run gc with 1.7.0.2.199.g90a2bf9; perhaps you could use something like oprofile to figure out where gc is spending most of its time.