Re: [PATCH v6 2/2] refs.c: SSE4.2 optimizations for check_refname_component

From: David Turner <dturner@twopensource.com>
Date: Jun 5, 2014, 19:26 UTC
Message-ID: <1401996362.18134.179.camel@stross>
In-Reply-To: <539062D9.60000@web.de>

On Thu, 2014-06-05 at 14:30 +0200, Torsten Bögershausen wrote:

Show 12 quoted lines

> On 2014-06-04 23.16, David Turner wrote:
> > 
> > Sure!  I actually went with > 120k to make measurement easier:
> > https://github.com/dturner-tw/many-refs
> Hm, I didn't get so man
> 
> git remote -v
> origin  https://github.com/dturner-tw/many-refs 
> 
>  wc .git/packed-refs 
>      750    1130   38868 .git/packed-refs
>

Oops. It looks like I forgot to push all of the refs. And when I try, it fails with "fatal: cannot exec 'send-pack': Argument list too long"

I hacked git to send batches of 1000; maybe I'll actually make a real patch with ARG_MAX at some point. Anyway, this is uploading now, but I estimate that it will take at least five hours, because github is being really slow about this.

...

> where only patch 1/2 doesn't seem to speed up things on my system:

...

I would not expect a noticeable change on a tiny number of refs; it's only when ref parsing takes up a large percentage of runtime -- tens of thousands of refs.