From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <junkio@cox.net>
Subject: Re: how to speed up "git log"?
Date: Sun, 11 Feb 2007 20:08:37 -0800
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Cc: Bruno Haible <bruno@clisp.org>,
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To: Robin Rosenberg <robin.rosenberg.lists@dewire.com>
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Robin Rosenberg <robin.rosenberg.lists@dewire.com> writes:

>> No, it became even worse: git-1.5.0-rc4 is twice as slow as git-1.4.4 for
>> this command:
>>   git-1.4.4: 25 seconds real time, 24 seconds of CPU time (12 user, 12 system)
>>   git-1.5.0: 50 seconds real time, 39 seconds of CPU time (20 user, 19 system)
>
> Could the UTF-8 stuff have anything to do with this?

I doubt it -- sliding mmap() in the current git, while is a good
change overall for handling really huge repos, would most likely
perform poorer than the fixed mmap() in 1.4.4 series on
platforms with slow mmap(), most notably on MacOS X.

It _might_ be possible that turning some sliding mmap() calls
into pread() makes it perform better on MacOS X.

I wonder what happens it git is compiled with NO_MMAP there...