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From: Nicolas Pitre <nico@cam.org>
To: Jon Smirl <jonsmirl@gmail.com>
Cc: Git Mailing List <git@vger.kernel.org>
Subject: Re: Performance problem, long run of identical hashes
Date: Mon, 10 Dec 2007 10:45:49 -0500 (EST)	[thread overview]
Message-ID: <alpine.LFD.0.99999.0712101037270.555@xanadu.home> (raw)
In-Reply-To: <9e4733910712100707i66e185bofe22805b8e0ba4d8@mail.gmail.com>

On Mon, 10 Dec 2007, Jon Smirl wrote:

> Running oprofile during my gcc repack shows this loop as the hottest
> place in the code by far.

Well, that is kind of expected.

> I added some debug printfs which show that I
> have a 100,000+ run of identical hash entries. Processing the 100,000
> entries also causes RAM consumption to explode.

That is impossible.  If you look at the code where those hash entries 
are created in create_delta_index(), you'll notice a hard limit of 
HASH_LIMIT (currently 64) is imposed on the number of identical hash 
entries.


Nicolas

  reply	other threads:[~2007-12-10 15:46 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-12-10 15:07 Performance problem, long run of identical hashes Jon Smirl
2007-12-10 15:45 ` Nicolas Pitre [this message]
2007-12-10 16:14   ` David Kastrup
2007-12-10 16:20   ` Jon Smirl
2007-12-10 16:30     ` Nicolas Pitre
2007-12-10 19:39   ` David Kastrup
2007-12-10 20:11     ` Nicolas Pitre

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