From mboxrd@z Thu Jan  1 00:00:00 1970
From: Yiannis Marangos <yiannis.marangos@gmail.com>
Subject: Re: [PATCH v7 2/2] Verify index file before we opportunistically
 update it
Date: Fri, 11 Apr 2014 18:58:57 +0300
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To: Torsten =?iso-8859-1?Q?B=F6gershausen?= <tboegi@web.de>
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On Fri, Apr 11, 2014 at 09:47:09AM +0200, Torsten B=F6gershausen wrote:
>   6. process A applies a commit:
>       - read the index into memory
>       - take the lock
>       - update the index file on disc
>       - release the lock

So here we can have race condition. Maybe we should implement Duy's
idea of verifying the sha1 in write_index()?


> The new code works like this:
>
>   8. process B applies a commit:
>       - take the lock
>       - verifies tha the index file on disc has the same sha as the o=
ne read before
>       # And if not: What do we do? die() or retry() ?
>       - update the index file on disc
>       - release the lock

IMO, we must never die() if we want to do opportunistic update and we
should never retry because it's a bit expensive if we do opportunistic =
update.


--
Yiannis