From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Shawn O. Pearce" <spearce@spearce.org>
Subject: Re: git-index-pack really does suck..
Date: Tue, 3 Apr 2007 17:37:10 -0400
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References: <Pine.LNX.4.64.0704030754020.6730@woody.linux-foundation.org> <db69205d0704031227q1009eabfhdd82aa3636f25bb6@mail.gmail.com> <Pine.LNX.4.64.0704031304420.6730@woody.linux-foundation.org> <alpine.LFD.0.98.0704031625050.28181@xanadu.home> <Pine.LNX.4.64.0704031346250.6730@woody.linux-foundation.org> <20070403210319.GH27706@spearce.org> <Pine.LNX.4.64.0704031411320.6730@woody.linux-foundation.org> <20070403211709.GJ27706@spearce.org> <alpine.LFD.0.98.0704031730300.28181@xanadu.home>
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Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	Chris Lee <clee@kde.org>, Junio C Hamano <junkio@cox.net>,
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To: Nicolas Pitre <nico@cam.org>
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Nicolas Pitre <nico@cam.org> wrote:
> First, I truly believe we should have a 64-bit pack index and fewer 
> larger packs than many small packs.

I'll buy that.  ;-)
 
> Which leaves us with the actual pack index lookup.  At that point the 
> cost of finding an existing object and finding that a given object 
> doesn't exist is about the same thing, isn't it?

Here's the rub:  in the missing object case we didn't find it
in the pack index, but it could be loose.  That's one failed
syscall per object if the object isn't loose.  If the object
isn't loose, it could be that it was *just* removed by a
running prune-packed, and the packfile that it was moved
to was created after we scanned for packfiles, so time to
rescan...

-- 
Shawn.