From: Nicolas Pitre <nico@cam.org>
Date: Thu, 31 May 2007 03:24:55 GMT
Subject: Re: [PATCH] always start looking up objects in the last used pack first
Message-ID: <alpine.LFD.0.99.0705302320530.11491@xanadu.home>
In-Reply-To: <alpine.LFD.0.99.0705302152180.11491@xanadu.home>

On Wed, 30 May 2007, Nicolas Pitre wrote:

> To test this I split the Linux repository into 66 packs and performed a
> "time git-rev-list --objects --all > /dev/null".  Best results are as 
> follows:
> 
> 	Pack Sort			w/o this patch	w/ this patch
> 	-------------------------------------------------------------
> 	recent objects last		26.4s		20.9s
> 	recent objects first		24.9s		18.4s
> 
> This shows that the pack order based on object age has some influence, 
> but that the last-used-pack heuristic is even more significant in 
> reducing object lookup.

For reference, the same operation on a fully packed into a single pack 
repository takes 17.1s.  So this looks damn good to me.


Nicolas