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Date: Thu, 13 Oct 2011 21:59:00 -0000
From: Jan Kratochvil <jan.kratochvil@redhat.com>
To: "Joseph S. Myers" <joseph@codesourcery.com>
Cc: Phil Muldoon <pmuldoon@redhat.com>, gdb@sourceware.org
Subject: Re: GIT and CVS
Message-ID: <20111013215927.GA13931@host1.jankratochvil.net>
References: <m3sjmwn0nh.fsf@redhat.com> <Pine.LNX.4.64.1110132017120.23193@digraph.polyomino.org.uk> <m3obxkmx2i.fsf@redhat.com> <Pine.LNX.4.64.1110132135270.23193@digraph.polyomino.org.uk>
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On Thu, 13 Oct 2011 23:50:33 +0200, Joseph S. Myers wrote:
> Even with local disk, git is much more I/O intensive.  I timed looking at 
> logs from a glibc checkout on local disk:
> 
> $ time git log > /dev/null
> 
> real    0m18.324s
> user    0m0.560s
> sys     0m0.304s

$ time git log >/dev/null

real	0m0.374s
user	0m0.330s
sys	0m0.041s

You cannot count the first operation, before ./.git gets cached.  The first
read is deficiency of kernel filesystem, pre-read and/or no SSD on your system.


Regards,
Jan