Recommended BUFFERS Wont Work for import

[Azeemuddin, Basheer]

Hi
From the IBM tutorials -- Performance Problem Determination, recommends
that BUFFERS should be set to 50% - 75% of Available Free mem

I have 2 GB (2097152) on my AIX 4.3.3 (No Apps other than 1 Informix App)

50% of 2097152 = 1048576

I tried dbimport (about 10 GB DB) with BUFFERS 140000

Got 567 & 116 ISAM Can't Allocate memory,
It reduced import time by 4 Hours.

What percentages you have. Anybody have close to 50 -75 %


Thanks
Basheer

sending to informix-list

[Mark Denham]

Look at the settings for SHMVIRSIZE, SHMADD and SHMTOTAL.

At the time of the failure a sort was in progress. Don't know how much data
you are loading, so I am assuming that you have not got these settings
correct. Shat values do you have? As a yardstick for the import you might
want to start with SHMVIRTSIZE = 256000 and SHMADD to 128000. Set SHMTOTAL =
0. This will allow the engine to allocate as much as it needs [can grab].

Mark

----- Original Message -----
From: "Azeemuddin, Basheer" <bahmed@knrq.com>
To: <informix-list@iiug.org>
Sent: Tuesday, October 21, 2003 12:33
Subject: Recommended BUFFERS Wont Work for import

> Hi
> From the IBM tutorials -- Performance Problem Determination, recommends
> that BUFFERS should be set to 50% - 75% of Available Free mem
>
> I have 2 GB (2097152) on my AIX 4.3.3 (No Apps other than 1 Informix App)
>
> 50% of 2097152 = 1048576
>
> I tried dbimport (about 10 GB DB) with BUFFERS 140000
>
> Got 567 & 116 ISAM Can't Allocate memory,
> It reduced import time by 4 Hours.
>
> What percentages you have. Anybody have close to 50 -75 %
>
>
> Thanks
> Basheer
>
> sending to informix-list

sending to informix-list

[Richard Kofler]

"Azeemuddin, Basheer" wrote:

>
> Hi
> From the IBM tutorials -- Performance Problem Determination, recommends
> that BUFFERS should be set to 50% - 75% of Available Free mem
>
> I have 2 GB (2097152) on my AIX 4.3.3 (No Apps other than 1 Informix App)
>
> 50% of 2097152 = 1048576
>
> I tried dbimport (about 10 GB DB) with BUFFERS 140000
>
> Got 567 & 116 ISAM Can't Allocate memory,
> It reduced import time by 4 Hours.
>
> What percentages you have. Anybody have close to 50 -75 %
>
> Thanks
> Basheer
>
> sending to informix-list

I do it this way:
sum(Buffers + shmvirtsize) approx 50%
if only a DB server, else less

In very short:
onstat -
shows you half of the physical memory
in the machine, if you have only 1 V type seg
in your onstat -g seg output
That is always a starting point for me.

dic_k
--
Richard Kofler
SOLID STATE EDV
Dienstleistungen GmbH
Vienna/Austria/Europe