Thanks heaps for the advice. I will do some benchmarks to see how long it takes to cluster all of the database tables.
Cheers,
Jeremy
-----Original Message-----
From: Kevin Grittner [mailto:Kevin.Grittner@wicourts.gov]
Sent: Tuesday, 25 January 2011 1:02 p.m.
To: Jeremy Palmer; Tom Lane
Cc: Robert Haas; pgsql-performance@postgresql.org; andy@squeakycode.net
Subject: RE: [PERFORM] Possible to improve query plan?
Jeremy Palmer <JPalmer@linz.govt.nz> wrote:
> My only question is how often will I need to re-cluster the
> table, because it comes at quite a cost.
I probably should have mentioned that the CLUSTER will run faster if
the data is already mostly in the right sequence. You'll be doing a
nearly sequential pass over the heap, which should minimize seek
time, especially if the OS notices the pattern and starts doing
sequential read-ahead.
-Kevin
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