From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCHv2 2/3] revision.c: introduce --min-parents and
 --max-parents
Date: Mon, 21 Mar 2011 10:45:53 -0700
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Cc: git@vger.kernel.org, Jeff King <peff@peff.net>,
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To: Michael J Gruber <git@drmicha.warpmail.net>
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In-Reply-To: <41d12c53966faa9c9cb5acc7646e9098dcd911ea.1300702130.git.git@drmicha.warpmail.net> (Michael J. Gruber's message of "Mon, 21 Mar 2011 11:14:06 +0100")
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Michael J Gruber <git@drmicha.warpmail.net> writes:

> Implementation note:
>
> We compute the number of parents only when we limit by that, so there
> is no performance impact when there are no limiters.

Only about 16% of the commits in git.git (and 7% in the kernel) are two
parent merges and the rest are mostly single strand of pearls, so even the
cost of counting all the parents in a loop that does not exit early when
it reaches max-parents limit should be negligible, and checking against
max-parents in each iteration would probably costs even more.

So I think this is a good to go.

Thanks.