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To: Simon Riggs <simon@2ndQuadrant.com>
cc: "Jonah H. Harris" <jonah.harris@gmail.com>,
	Alex Hunsaker <badalex@gmail.com>, Kenneth Marshall <ktm@rice.edu>,
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Subject: Re: hash index improving v3 
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Comments: In-reply-to Simon Riggs <simon@2ndQuadrant.com>
	message dated "Tue, 23 Sep 2008 06:15:36 +0100"
Date: Tue, 23 Sep 2008 08:16:34 -0400
Message-ID: <25193.1222172194@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Simon Riggs <simon@2ndQuadrant.com> writes:
> maintenance_work_mem is already used for 3 separate operations that bear
> little resemblance to each other. If it's appropriate for all of those
> then its appropriate for this usage also.

No, it isn't.

The fundamental point here is that this isn't a memory allocation
parameter; it's a switchover threshold between two different behaviors.

			regards, tom lane