We are about to upgrade to a 6 x 750 MHZ from a 4 x 450 MHZ.  At that point,
I will consider doing more bufferpool.  The problem is the buffer processing
does use some CPU resources, especially during expiration.  So, I will be
able to model the benefits.  We are adding 2GB of memory (total 4GB), so I
may run my bufferpool up to a gigabyte.

Paul D. Seay, Jr.
Technical Specialist
Naptheon Inc.
757-688-8180


-----Original Message-----
From: Paul Ripke [mailto:stixpjr AT BIGPOND.NET DOT AU]
Sent: Friday, January 17, 2003 8:48 PM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: Sizing of Bufpoolsize, everyone take note of this response


On Saturday, January 18, 2003, at 02:36 AM, Seay, Paul wrote:

> As Zorg would say, I know the sound of this music.
>
> The default maxperm is probably killing you.  I am guessing you are
> swapping
>
> <snip>

I agree whole-heartedly! I'd go a step further, and knock maxperm down to
about 10%, or even less. Given the nature of TSM I/O, the AIX buffer cache
is going to be next to useless. It may then be possible to expand the TSM
bufpoolsize beyond recommendations... I've set mine to about 60-70% physical
RAM, up from 30-40%. The speed of selects and "q actlog" have increased by
an order of magnitude. Definitely stay below the level where the system
starts to swap, and don't go too large... TSM buffer cache management can
then become a bottleneck. How big is too large? No idea - it'd be very
dependent on hardware - experiment and see!

Cheers,
--
Paul Ripke
Unix/OpenVMS/DBA
101 reasons why you can't find your Sysadmin:
68: It's 9AM. He/She is not working that late.
-- Koos van den Hout