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To: Simon Riggs <simon@2ndQuadrant.com>
cc: List pgsql-patches <pgsql-patches@postgresql.org>,
	pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: [PATCHES] Infrastructure changes for recovery 
In-reply-to: <1222691596.4445.1188.camel@ebony.2ndQuadrant> 
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Comments: In-reply-to Simon Riggs <simon@2ndQuadrant.com>
	message dated "Mon, 29 Sep 2008 13:33:16 +0100"
Date: Mon, 29 Sep 2008 08:46:46 -0400
Message-ID: <10307.1222692406@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Simon Riggs <simon@2ndQuadrant.com> writes:
> ... That kinda works, but the problem is that restartpoints are time based,
> not log based. We need them to be deterministic for us to rely upon them
> in the above way.

Right, but the performance disadvantages of making them strictly
log-distance-based are pretty daunting.  We don't really want slaves
doing that while they're in catchup mode.

			regards, tom lane