From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH v2 04/12] refs: implement simple transactions for the packed-refs file
Date: Thu, 20 Jun 2013 10:11:02 -0700
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Cc: Jeff King <peff@peff.net>, Johan Herland <johan@herland.net>,
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To: Michael Haggerty <mhagger@alum.mit.edu>
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In-Reply-To: <51C2B41F.2050708@alum.mit.edu> (Michael Haggerty's message of
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Michael Haggerty <mhagger@alum.mit.edu> writes:

> But currently only the main packed ref cache can be locked, so it would
> be possible for lock_packed_refs() to use the static packlock instance
> for locking.

Perhaps I am missing something from the previous discussions, but I
am having trouble understanding the "main packed ref cache" part of
the above.  "main" as opposed to...?  Is it envisioned that later
somebody can lock one subpart while another can lock a different and
non-overlapping subpart, to make changes independently, and somehow
their non-overlapping changes will be consolidated into a single
consistent result?