Re: Slow count(*) again...

From: david(at)lang(dot)hm
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Neil Whelchel <neil(dot)whelchel(at)gmail(dot)com>, pgsql-performance(at)postgresql(dot)org
Subject: Re: Slow count(*) again...
Date: 2010-10-13 19:37:45
Message-ID: alpine.DEB.2.00.1010131237010.30818@asgard.lang.hm
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers pgsql-performance

On Wed, 13 Oct 2010, Tom Lane wrote:

> Neil Whelchel <neil(dot)whelchel(at)gmail(dot)com> writes:
>
> That's probably got little to do with caching and everything to do with
> setting hint bits on the first SELECT pass.
>
> I concur with Mark's question about whether your UPDATE pushed the table
> size across the limit of what would fit in RAM.

Neil, can you just double the size of your initial test to make sure that
it's too large to fit in ram to start with?

David Lang

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Neil Whelchel 2010-10-13 20:08:26 Re: Slow count(*) again...
Previous Message Peter Eisentraut 2010-10-13 19:37:03 Re: host name support in pg_hba.conf

Browse pgsql-performance by date

  From Date Subject
Next Message Neil Whelchel 2010-10-13 20:08:26 Re: Slow count(*) again...
Previous Message Mladen Gogala 2010-10-13 19:35:02 Re: Bogus startup cost for WindowAgg