Date: Fri, 7 Apr 2006 16:16:02 -0400
From: "D'Arcy J.M. Cain" <darcy@druid.net>
To: Gavin Hamill <gdh@laterooms.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: pg 8.1.3, AIX, huge box, painfully slow.
Message-Id: <20060407161602.7ed5f672.darcy@druid.net>
In-Reply-To: <20060407205919.a091da26.gdh@laterooms.com>
References: <20060407185823.abe93017.gdh@laterooms.com>
	<1144436060.32269.13.camel@state.g2switchworks.com>
	<20060407205919.a091da26.gdh@laterooms.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit

On Fri, 7 Apr 2006 20:59:19 +0100
Gavin Hamill <gdh@laterooms.com> wrote:
> > I'd put the old 4 way Xeon back in production and do some serious
> > testing of this pSeries machine.  IBM should be willing to help you, I
> > hope.
> 
> They probably would if this had been bought new - as it is, we have
> rented the machine for a month from a 2nd-user dealer to see if it's
> capable of taking the load. I'm now glad we did this. 

We also had problems with a high end AIX system and we got no help from
IBM.  They expected you to put Oracle on and if you used anything else
you were on your own.  We had exactly the same issue.  We expected to
get an order of magnitude improvement and instead the app bogged down.
It also got worse over time.  We had to reboot every night to get
anything out of it.  Needless to say, they got their system back.

> 
> > My guess is that this is an OS issue.  Maybe there are AIX tweaks that
> > will get it up to the same or higher level of performance as your four
> > way xeon.  Maybe there aren't.
> 
> The pSeries isn't much older than our Xeon machine, and I expected the
> performance level to be exemplary out of the box.. we've enabled the
> 64-bit kernel+userspace, and compiled pg for 64-bitness with the gcc
> flags as reccommended by Senica Cunningham on this very list..

That's Seneca.

We found that our money was better spent on multiple servers running
NetBSD with a home grown multi-master replication system.  Need more
power?  Just add more servers.

-- 
D'Arcy J.M. Cain <darcy@druid.net>         |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.