From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: Git Scaling: What factors most affect Git performance for a large repo?
Date: Fri, 20 Feb 2015 13:04:30 -0800
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Cc: Duy Nguyen <pclouds@gmail.com>,
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To: =?utf-8?B?w4Z2YXIgQXJuZmrDtnLDsA==?= Bjarmason <avarab@gmail.com>
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=C3=86var Arnfj=C3=B6r=C3=B0 Bjarmason <avarab@gmail.com> writes:

> I actually ran this a few times while testing it, so this is a before
> and after on a hot cache of linux.git with 406 tags v.s. ~140k. I ran
> the gc + repack + bitmaps for both repos noted in an earlier reply of
> mine, and took the fastest run out of 3:
>
>     $ time (git log master -100 >/dev/null)
>     Before: real    0m0.021s
>     After: real    0m2.929s

Do you force --decorate with some config?  Or do you see similar
performance difference with "git rev-parse master", too?

>     $ time (git status >/dev/null)
>     # Around 150ms, no noticeable difference

This is understandable, as it will not look at any ref other than
HEAD.