Re: Possible to improve query plan?

From: "Kevin Grittner" <Kevin(dot)Grittner(at)wicourts(dot)gov>
To: "Jeremy Palmer" <JPalmer(at)linz(dot)govt(dot)nz>, "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: "Robert Haas" <robertmhaas(at)gmail(dot)com>, "pgsql-performance(at)postgresql(dot)org" <pgsql-performance(at)postgresql(dot)org>, "andy(at)squeakycode(dot)net" <andy(at)squeakycode(dot)net>
Subject: Re: Possible to improve query plan?
Date: 2011-01-25 00:01:31
Message-ID: 4D3DBE7B0200002500039B94@gw.wicourts.gov
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

Jeremy Palmer <JPalmer(at)linz(dot)govt(dot)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

In response to

Responses

Browse pgsql-performance by date

  From Date Subject
Next Message Jeremy Palmer 2011-01-25 00:24:48 Re: Possible to improve query plan?
Previous Message Kevin Grittner 2011-01-24 23:54:53 Re: Possible to improve query plan?