pg.ddx.io  pgsql-performance@postgresql.org mailing list archive  
help / color / mirror / Atom feed
From: Glenn Sullivan <glenn.sullivan@varianinc.com>
To: pgsql-performance@postgresql.org
Subject: Performance of ORDER BY
Date: Tue, 05 Dec 2006 10:12:03 -0700
Message-ID: <4575A863.6040504@varianinc.com> (raw)

I am wanting some ideas about improving the performance of ORDER BY in
our use.  I have a DB on the order of 500,000 rows and 50 columns.
The results are always sorted with ORDER BY.  Sometimes, the users end up
with a search that matches most of the rows.  In that case, I have a
LIMIT 5000 to keep the returned results under control.  However, the
sorting seems to take 10-60 sec.  If I do the same search without the
ORDER BY, it takes about a second.  

I am currently on version 8.0.1 on Windows XP using a Dell Optiplex 280
with 1Gb of ram.  I have set sort_mem=100000 set.

Any ideas?

Thanks,
Glenn




view thread (8+ messages)  latest in thread

Message-ID: <4575A863.6040504@varianinc.com>
Permalink:  ../4575A863.6040504@varianinc.com/
Also on:    postgresql.org/message-id/4575A863.6040504@varianinc.com

 · 

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: pgsql-performance@postgresql.org
  Cc: glenn.sullivan@varianinc.com
  Subject: Re: Performance of ORDER BY
  In-Reply-To: <4575A863.6040504@varianinc.com>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox