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Message-ID: <4FD458CA.3070902@optrak.com>
Date: Sun, 10 Jun 2012 09:20:26 +0100
From: Mark Thornton <mthornton@optrak.com>
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To: pgsql-performance@postgresql.org
Subject: Performance of CLUSTER
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What is the expected performance of cluster and what tuning parameters 
have most effect?

I have a set of 5 tables with identical structure (all inherit a common 
table). The sizes given are total relation size. The clustering index is 
a gist index on a (non null) geographic(linestring) column

1. 327600 rows, 105MB, 15.8s
2. 770165 rows, 232MB, 59.5s
3. 1437041 rows, 424MB, 140s
4. 3980922 rows, 1167MB, 276s
5. 31843368 rows, 9709MB, ~ 10 hours

Server is version 9.1. with postgis 1.5.4.

Regards,
Mark Thornton