From mboxrd@z Thu Jan  1 00:00:00 1970
From: Chris Mason <mason@suse.com>
Subject: Re: kernel.org and GIT tree rebuilding
Date: Sun, 26 Jun 2005 16:52:57 -0400
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References: <20050624.212009.92584730.davem@davemloft.net> <Pine.LNX.4.58.0506242257450.11175@ppc970.osdl.org> <Pine.LNX.4.58.0506260905200.19755@ppc970.osdl.org>
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Cc: Jeff Garzik <jgarzik@pobox.com>,
	"David S. Miller" <davem@davemloft.net>,
	Git Mailing List <git@vger.kernel.org>,
	Nicolas Pitre <nico@cam.org>
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To: Linus Torvalds <torvalds@osdl.org>
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On Sunday 26 June 2005 12:41, Linus Torvalds wrote:
> On Fri, 24 Jun 2005, Linus Torvalds wrote:
> > yeah, it clearly needs some refining to be useful, but I think you can
> > kind of see how it would work.
>
> Ok, here's how it works.
>
>  - Pick a starting commit (or a hundred)
>
>  - Pick an ending commit (or a hundred)
>
>  - generate the list of objects in between them
>
> 	git-rev-list --object end ^start > object-list
>
>  - Pack that list of objects into an "object pack":
>
> 	git-pack-objects out < object-list

Without having read the code, the big thing that hurt performance in my early 
packed file work was compressing the whole packed file instead of individual 
sub-objects.  It takes more room to compress each object, but when I 
compressed the whole thing read performance was quite bad.

-chris