UNIX for Dummies Questions & Answers

Hi folks,

Lately my RS 6000 server is giving some problems.
Needs a reboot from time to time (4-8 days)

Specs:

IBM/RS6000
Unix 4.3
3 gigabyte memory

I keep getting messages like :

" The fork function failed "

I have raised the paging space from 1 gigabyte to 3 gigabyte,
But when I monitor my system using the monitor command it states:

Memory Real Virtual
free 1802 MB 0 MB
files 416 MB
total 1024 MB 612 MB

When i use the lsps -a command :

Page Space Physical Volume Volume Group Size %Used
hd6 hdisk0 rootvg 3072MB 28

Can anyone explain, or tell me how to read the screen from the monitor command?

Thanx in advance,

Hi,

When fork fails it usally means that there are no room for more processes.

There should be some kernel parameter you can raise in AIX to allow more processes. I doubt that you are running out of processes because of high usage. It sounds like you have a program that bugged out and just keeps on forking new processes until the system dies..

Keep a close watch with the ps command and check how many processes are running and if you get more and more every day check whoes spawning them..

Just a thought..

Hope it helps

/Peter

To look if the problem is with the total number of processes
you can install and configure the PDT (Perfomance Diagnostic
Tool). To configure run:

/usr/sbin/perf/diag_tool/pdt_config

Collect data for a week and run the report

/usr/sbin/perf/diag_tool/pdt_report

If the problem is with nprocess change it.

To see the actual value

lsattr -E -l sys0

to change:

chdev -l sys0 -a maxuproc=600

Regards. Hugo.