From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Turner <dturner@twopensource.com>
Subject: Re: git reset for index restoration?
Date: Thu, 22 May 2014 14:08:16 -0400
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To: Jeff King <peff@peff.net>
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On Thu, 2014-05-22 at 12:46 -0400, Jeff King wrote:
> On Thu, May 22, 2014 at 12:22:43PM -0400, David Turner wrote:
> 
> > If I have a git repository with a clean working tree, and I delete the
> > index, then I can use git reset (with no arguments) to recreate it.
> > However, when I do recreate it, it doesn't come back the same.  I have
> > not analyzed this in detail, but the effect is that commands like git
> > status take much longer because they must read objects out of a pack
> > file.  In other words, the index seems to not realize that the index (or
> > at least most of it) represents the same state as HEAD.  If I do git
> > reset --hard, the index is restored to the original state (it's
> > byte-for-byte identical), and the pack file is no longer read.
> 
> Are you sure it's reading a packfile?

Well, it's calling inflate(), and strace says it is reading
e.g. .git/objects/pack/pack-....{idx,pack}.

So, I would say so.