From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <junkio@cox.net>
Subject: Re: git-index-pack really does suck..
Date: Tue, 03 Apr 2007 14:44:13 -0700
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Cc: Nicolas Pitre <nico@cam.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Chris Lee <clee@kde.org>,
	Git Mailing List <git@vger.kernel.org>
To: "Shawn O. Pearce" <spearce@spearce.org>
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"Shawn O. Pearce" <spearce@spearce.org> writes:

> 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...

If that is the only reason we have these reprepare_packed_git()
sprinkled all over in sha1_file.c (by 637cdd9d), perhaps we
should rethink that.  Is there a cheap way to trigger these
rescanning only when a prune-packed is in progress, I wonder...