From: David Bremner <david@tethera.net>
To: Mark Walters <markwalters1009@gmail.com>, notmuch@notmuchmail.org
Subject: Re: [PATCH] dump: make dump take Xapian write lock
In-Reply-To: <1403554349-8888-1-git-send-email-markwalters1009@gmail.com>
References: <87zjhh67e7.fsf@qmul.ac.uk>
	<1403554349-8888-1-git-send-email-markwalters1009@gmail.com>
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Date: Tue, 15 Jul 2014 11:10:51 -0300
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Mark Walters <markwalters1009@gmail.com> writes:

>
> Discussion with Olly on irc indicates that this is currently the best
> solution: in xapian trunk there may be better possibilities using
> snapshots but they need to make it to a release and propogate out to
> users before we can switch approach.

I agree that this seems to be the only feasible approach to make dump
atomic.  I'm a little unsure about the benefits to the end user though.
Currently, the user has to check the return code of dump to ensure it
completed correctly.  With this change, the user will still have to
check that dump did not error out when trying to acquire a write lock.
The following ticket

      http://trac.xapian.org/ticket/275

suggests that if we wanted to a blocking open, we'd be on our own.

Did I miss something here about the benefits? I agree that failing
earlier is nicer, but is that it?

d