memory allocation for programs

[Tom Wallin_1]

Michael,
I tried the ps -o but the ps cmd did not like the RSS or VSZ. It gives the msg - "ps: unknown variable in format: RSS".

I was wrong about the stack size not changing in my previous msg. The size did change.

[Hein van den Heuvel]

Oh, RSS could be the column header for display purposes, and rss the option field.
Just use 'man ps' and '/RSS'

Hein.

[Michael Schulte zur Sur · Accepted solution]

Hi,

try this:
ps -eo pid,rssize,vsize,command

greetings,

Michael

[Tom Wallin_1]

I got the ps -O thing now. Attached is the ps cmd from each server as a MS text file.

Tom Wallin

[Tom Wallin_1]

I have tried tha things suggested. We are still stuck with the same problem. I have moved the question to the "General" part of the forum.

Tom Wallin

[Tom Wallin_1]

I wanted to update this thread with the final fixes. Both were settings in sysconfigtab. One in the vm: section - vm_segmentation and one in the rt: section aio_task_max_num.
We started with a program that was taking 10MB of RSS per user. It turns out that the program itself takes 1.8MB of RSS. Another 3.6MB was taken when vm_segmentation was set to 1. This setting causes all libraries referenced by the program to be loaded with it into memory. This was for security purposes.
And the last amount of RSS 4.6MB was taken because we had the aio_task_max_num set to 60108. This setting causes the initialization routines in libaio to allocate 60108 aio result blocks. These are used to contain context for outstanding aio requests. At 80 bytes per result block the resulting memory allocation is 587 pages (4.6 Mbytes).
We think that the 60108 was set for Database purposes. But we are unsure why. We did not need the setting for Informix.

Tom Wallin