Subject: Re: Re: [COMMITTERS] pgsql: Make standby server
	continuously retry restoring the next WAL
From: Simon Riggs <simon@2ndQuadrant.com>
To: Fujii Masao <masao.fujii@gmail.com>
Cc: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>,
	Aidan Van Dyk <aidan@highrise.ca>,
	PostgreSQL-development <pgsql-hackers@postgresql.org>
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Date: Fri, 19 Mar 2010 08:52:04 +0000
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On Thu, 2010-03-18 at 23:27 +0900, Fujii Masao wrote:

> I agree that this is a bigger problem. Since the standby always starts
> walreceiver before replaying any WAL files in pg_xlog, walreceiver tries
> to receive the WAL files following the REDO starting point even if they
> have already been in pg_xlog. IOW, the same WAL files might be shipped
> from the primary to the standby many times. This behavior is unsmart,
> and should be addressed.

We might also have written half a file many times. The files in pg_xlog
are suspect whereas the files in the archive are not. If we have both we
should prefer the archive.

-- 
 Simon Riggs           www.2ndQuadrant.com