From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH] check_refname_component: Optimize
Date: Thu, 29 May 2014 09:36:33 -0700
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Cc: David Turner <dturner@twopensource.com>,
	Michael Haggerty <mhagger@alum.mit.edu>,
	Git Mailing List <git@vger.kernel.org>,
	David Turner <dturner@twitter.com>
To: Duy Nguyen <pclouds@gmail.com>
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	(Duy Nguyen's message of "Thu, 29 May 2014 20:41:52 +0700")
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Duy Nguyen <pclouds@gmail.com> writes:

> On Thu, May 29, 2014 at 6:49 AM, David Turner <dturner@twopensource.com> wrote:
>>> I assume that most of the time spent in check_refname_component() is
>>> while reading the packed-refs file, right?
>>
>> Yes.
>
> I wonder if we can get away without SSE code by saving stat info of
> the packed-refs version that we have verified. When we read pack-refs,
> if stat info matches, skip check_refname_component(). Assuming that
> pack-refs does not change often, of course.

Can you elaborate a bit more?

Regardless, I think I would prefer to see this patch done as at
least a two step series, one that does only the look-up table thing,
and then the other with arch-specific tweaks as a follow-up on top.