Subject: Re: [PATCHES] Infrastructure changes for recovery
From: Simon Riggs <simon@2ndQuadrant.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: List pgsql-patches <pgsql-patches@postgresql.org>,
	pgsql-hackers <pgsql-hackers@postgresql.org>
In-Reply-To: <18549.1221746983@sss.pgh.pa.us>
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Date: Thu, 18 Sep 2008 15:24:55 +0100
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On Thu, 2008-09-18 at 10:09 -0400, Tom Lane wrote:
> Simon Riggs <simon@2ndQuadrant.com> writes:
> > On Thu, 2008-09-18 at 09:06 -0400, Tom Lane wrote:
> >> Do we really need a checkpoint there at all?
> 
> > "Timelines only change at shutdown checkpoints".
> 
> Hmm.  I *think* that that is just a debugging crosscheck rather than a
> critical property.  But yeah, it would take some close investigation,
> which maybe isn't warranted if you have a less-invasive solution.

The important thing is that everybody uses the new timelineid.

AFAICS we actually write new timelineids into the WAL file if the
previous timelineid, so it can't be that risky.

Ignore v5 then and look for v6 on Monday. Hopefully the final one :-)

-- 
 Simon Riggs           www.2ndQuadrant.com
 PostgreSQL Training, Services and Support