From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH 0/2] Retry attempts to acquire the packed-refs lock
Date: Sat, 02 May 2015 19:12:06 -0700
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References: <1430491977-25817-1-git-send-email-mhagger@alum.mit.edu>
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Cc: Stefan Beller <sbeller@google.com>, Jeff King <peff@peff.net>,
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To: Michael Haggerty <mhagger@alum.mit.edu>
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In-Reply-To: <1430491977-25817-1-git-send-email-mhagger@alum.mit.edu> (Michael
	Haggerty's message of "Fri, 1 May 2015 16:52:55 +0200")
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Michael Haggerty <mhagger@alum.mit.edu> writes:

> At GitHub we were seeing occasional lock contention over packed-refs.
> It wasn't very common, but when you have as much git traffic as we
> have, anything that *can* happen *will* happen.
>
> The problem is that Git only tries to acquire locks a single time. If
> that attempt fails, the whole process fails. So, for example, if two
> processes are trying to delete two different references, one of them
> can fail due to inability to acquire the packed-refs lock, even though
> it could have succeeded if it had just waited a moment.

Yeah, try and abort may be perfectly fine for Git used interactively
by humans, but is totally unsuitable for the server side.  Thanks
for looking into this.