From mboxrd@z Thu Jan  1 00:00:00 1970
From: Vicent Marti <tanoku@gmail.com>
Subject: Re: Using libgit2 code in git.git as a Google Summer of Code project?
Date: Fri, 11 Mar 2011 14:22:25 +0200
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Cc: Jonathan Nieder <jrnieder@gmail.com>, libgit2@librelist.com,
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To: Junio C Hamano <gitster@pobox.com>
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Hey,

On Thu, Mar 10, 2011 at 9:27 PM, Junio C Hamano <gitster@pobox.com> wrote:
> How big a performance penalty does libgit2 have to pay to depart from many
> "we run once and let exit take care of cleaning up after us" patterns used
> in git.git primarily in order to avoid the housekeeping cost?

It's not significant. We try to use custom memory allocation wherever
possible, and the most complex structures (interdependencies in parsed
objects from the DAG) are internally garbage collected, so we don't do
any unnecessary free's. We try to offset the cost of 'proper' memory
management by using smarter/more performance tuned algorithms. So far,
some stuff ranges from varying degrees of faster-than-git (see: new
revision walker, index writing, streaming loose object writes) to
slightly slower (see object parsing :/).

We are working on it. Performance is our main concern.

Cheers,
Vicent