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

Re: [GENERAL] Upgrade to dual processor machine?

From: Josh Berkus <josh(at)agliodbs(dot)com>
To: "Henrik Steffen" <steffen(at)city-map(dot)de>
Cc: <pgsql-performance(at)postgresql(dot)org>
Subject: Re: [GENERAL] Upgrade to dual processor machine?
Date: 2002-11-15 18:55:11
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-generalpgsql-performance

> > Well, now it gets more complicated.   You need to determine:
> > A) The median processing time of each of those requests.
> > B) The amount of Sort_mem actually required for each request.
> as I am dealing with postgres for a webserver the median processing
> time of each request has got to be <1 sec. how can i measure
> the amount of sort_mem needed?

Through experimentation, mostly.  SInce you are in a high-volume, small-query 
environment, I would try *lowering* your sort mem to see if that has an 
adverse impact on queries.   A good quick test would be to cut your sort_mem 
in half, and then run an EXPLAIN on the query from which you expect the 
largest result set, and see if the SORT time on the query has been increased.

-Josh Berkus
 Aglio Database Solutions
 San Francisco

In response to

pgsql-performance by date

Next:From: Josh BerkusDate: 2002-11-15 19:27:29
Subject: Re: Sort time
Previous:From: Rod TaylorDate: 2002-11-15 18:48:23
Subject: Re: Sort time

pgsql-general by date

Next:From: Robert TreatDate: 2002-11-15 19:01:48
Subject: Re: Postgres Support
Previous:From: Stephan SzaboDate: 2002-11-15 18:41:39
Subject: Re: Basic Trigger Question

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