Message-ID: <519E873D.5000406@nasby.net>
Date: Thu, 23 May 2013 16:16:45 -0500
From: Jim Nasby <jim@nasby.net>
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To: Greg Smith <greg@2ndQuadrant.com>
CC: Amit Kapila <amit.kapila@huawei.com>,
	'PostgreSQL-development' <pgsql-hackers@postgreSQL.org>
Subject: Re: Move unused buffers to freelist
References: <002f01ce50a8$e057c7a0$a10756e0$@kapila@huawei.com>
	<51928CDA.7030009@2ndQuadrant.com>
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On 5/14/13 2:13 PM, Greg Smith wrote:
> It is possible that we are told to put something in the freelist that
> is already in it; don't screw up the list if so.
>
> I don't see where the code does anything to handle that though.  What was your intention here?

IIRC, the code that pulls from the freelist already deals with the possibility that a block was on the freelist but has since been put to use. If that's the case then there shouldn't be much penalty to adding a block multiple times (at least within reason...)
-- 
Jim C. Nasby, Data Architect                       jim@nasby.net
512.569.9461 (cell)                         http://jim.nasby.net


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