From mboxrd@z Thu Jan  1 00:00:00 1970
From: Anders Kaseorg <andersk@MIT.EDU>
Subject: Re: Performance issue of 'git branch'
Date: Thu, 23 Jul 2009 12:48:20 -0400 (EDT)
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Cc: "Carlos R. Mafra" <crmafra2@gmail.com>,
	Git Mailing List <git@vger.kernel.org>,
	Junio C Hamano <gitster@pobox.com>
To: Linus Torvalds <torvalds@linux-foundation.org>
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On Wed, 22 Jul 2009, Linus Torvalds wrote:
> It uses the "raw" version of 'for_each_ref()' (which doesn't verify t=
hat=20
> the ref is valid), and then does the "type verification" before it st=
arts=20
> doing any gentle commit lookup.

I submitted essentially the same patch in May:
  http://article.gmane.org/gmane.comp.version-control.git/120097
with the additional optimization that we don=E2=80=99t need to lookup c=
ommits at=20
all unless we=E2=80=99re using -v, --merged, --no-merged, or --contains=
=2E  In my=20
tests, it makes `git branch` 5 times faster on an uncached linux-2.6=20
repository.

Anders