From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: git pull takes ~8 seconds on up-to-date Linux git tree
Date: Thu, 04 Oct 2012 13:44:06 -0700
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Cc: Markus Trippelsdorf <markus@trippelsdorf.de>, git@vger.kernel.org
To: Jeff King <peff@peff.net>
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In-Reply-To: <7vhaqaxawh.fsf@alter.siamese.dyndns.org> (Junio C. Hamano's
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Junio C Hamano <gitster@pobox.com> writes:

> It gets more curious, though.
> ...
> However.
>
> If I revert 5802f81 that updated the implementation of fmt-merge-msg
> on top of 'master', *without* reverting 34f5130^2, I get ~4.5 seconds.
> As we are doing an "Already up-to-date" pull, I thought there is no
> need to call fmt-merge-msg in the first place?
>
> Which may indicate that "git merge" has been broken for a long time
> and making unnecessary calls.
>
> Hrmmm...

Actually there is nothing curious about this.  "git pull" prepares
the merge message before it calls "git rebase" or "git merge", and
there is no fast-path that detects "Already up-to-date" in it.