From mboxrd@z Thu Jan  1 00:00:00 1970
From: Duy Nguyen <pclouds@gmail.com>
Subject: Re: [PATCH 2/2] lookup_commit_reference_gently: do not read non-{tag,commit}
Date: Fri, 31 May 2013 07:52:09 +0700
Message-ID: <CACsJy8BDM=1xfZLvLs-G-0xnneaOAvzZOOXjdTZEtsT9PEvHeg@mail.gmail.com>
References: <2d926e4dbd218b2305f50652c00a5c1d87e81208.1369943791.git.trast@inf.ethz.ch>
 <5cc40825d5b4fb3382e4c054c49adf5e6b6fe110.1369943791.git.trast@inf.ethz.ch> <20130530212223.GA2135@sigill.intra.peff.net>
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Cc: Thomas Rast <trast@inf.ethz.ch>,
	Git Mailing List <git@vger.kernel.org>,
	Junio C Hamano <gitster@pobox.com>,
	Ramkumar Ramachandra <artagnon@gmail.com>,
	=?UTF-8?B?QWxleCBCZW5uw6ll?= <kernel-hacker@bennee.com>,
	Antoine Pelisse <apelisse@gmail.com>,
	John Keeping <john@keeping.me.uk>
To: Jeff King <peff@peff.net>
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On Fri, May 31, 2013 at 4:22 AM, Jeff King <peff@peff.net> wrote:
> On Thu, May 30, 2013 at 10:00:23PM +0200, Thomas Rast wrote:
>
>> lookup_commit_reference_gently unconditionally parses the object given
>> to it.  This slows down git-describe a lot if you have a repository
>> with large tagged blobs in it: parse_object() will read the entire
>> blob and verify that its sha1 matches, only to then throw it away.
>>
>> Speed it up by checking the type with sha1_object_info() prior to
>> unpacking.
>
> This would speed up the case where we do not end up looking at the
> object at all, but it will slow down the (presumably common) case where
> we will in fact find a commit and end up parsing the object anyway.

Perhaps turn "quiet" into a bitmap and only let git-describe do this?
--
Duy