Skip site navigation (1) Skip section navigation (2)

Re: 2GB or not 2GB

From: Simon Riggs <simon(at)2ndquadrant(dot)com>
To: josh(at)agliodbs(dot)com
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: 2GB or not 2GB
Date: 2008-05-31 07:44:57
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-performance
On Wed, 2008-05-28 at 16:59 -0700, Josh Berkus wrote:

> sort_mem: My tests with 8.2 and DBT3 seemed to show that, due to 
> limitations of our tape sort algorithm, allocating over 2GB for a single 
> sort had no benefit.  However, Magnus and others have claimed otherwise.  
> Has this improved in 8.3?

There is an optimum for each specific sort. 

Your results cannot be used to make a global recommendation about the
setting of work_mem. So not finding any benefit in your tests *and*
Magnus seeing an improvement are not inconsistent events.

 Simon Riggs 
 PostgreSQL Training, Services and Support

In response to


pgsql-performance by date

Next:From: Tom LaneDate: 2008-05-31 15:51:49
Subject: Re: Statistics issue
Previous:From: Vlad ArkhipovDate: 2008-05-30 11:02:41
Subject: Statistics issue

Privacy Policy | About PostgreSQL
Copyright © 1996-2017 The PostgreSQL Global Development Group