Re: How much expensive are row level statistics?

From: Alvaro Herrera <alvherre(at)commandprompt(dot)com>
To: Michael Fuhr <mike(at)fuhr(dot)org>
Cc: Carlos Benkendorf <carlosbenkendorf(at)yahoo(dot)com(dot)br>, pgsql-performance(at)postgresql(dot)org
Subject: Re: How much expensive are row level statistics?
Date: 2005-12-12 13:23:42
Message-ID: 20051212132342.GE19555@surnet.cl
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

Michael Fuhr wrote:
> On Sun, Dec 11, 2005 at 11:53:36AM +0000, Carlos Benkendorf wrote:
> > I would like to use autovacuum but is not too much expensive
> > collecting row level statistics?
>
> The cost depends on your usage patterns. I did tests with one of
> my applications and saw no significant performance difference for
> simple selects, but a series of insert/update/delete operations ran
> about 30% slower when block- and row-level statistics were enabled
> versus when the statistics collector was disabled.

This series of i/u/d operations ran with no sleep in between, right?
I wouldn't expect a normal OLTP operation to be like this. (If it is
you have a serious shortage of hardware ...)

--
Alvaro Herrera http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support

In response to

Responses

Browse pgsql-performance by date

  From Date Subject
Next Message Bealach-na Bo 2005-12-12 16:24:40 Re: Very slow queries - please help
Previous Message Steinar H. Gunderson 2005-12-12 12:04:54 Re: 7.4.7 vs. 8.1