HP-UX

Hi Experts,

We encountered problem in one of the production system where some processes were taking higher CPU and after some time it came back to normal..

From system prespective, is there any way to check why processes took more cpu during that particular period.

What processes are you talking about?
To see why is to be monitoring constantly... without more information from you it will be difficult to answer...

From system perspective, no. It's not psychic. Only the process itself "knows" what it's actually doing.

Maybe you can try tusc.
tusc-8.1(1)

There is nothing wrong with processes using CPU

Problem is, if your machine is constantly using 100% of CPU (you should have atleast 5% for system).

In general, you need to find out what is being ran @ that time you saw a spike of CPU usage (database layer if db is used).

The tools for developers are : tusc, gdb and execution plans (db)
The tools for system folks are : sar, lsof, iostat, vmstat, glance

I would like to emphasize sar here, as a most useful tool (at least for me) for constant monitoring on HPUX systems. Have it run in cron collecting data all the time.

Something like :

Code:

0       *       *       *       *       /usr/lbin/sa/sa1 300 12

Be sure to inspect the /usr/lbin/sa/sa1 script and select where you want the actual log (/var/adm/sa being default)

Then you will be able to inspect the files generated using sar -A -f /var/admsa/sadate
Check man sar for additional switches, there is plenty for everything.

There is also free software which will enable you to draw graphs from those files, or use awk to draw some conclusions.


Regards
Peasant.

And first of all, is there a problem and why/how?

Thanks all for the reply. As per your feedbacks I have sent along the ouput of sar command to them.

However my higher management is asking the reason for sudden spike in cpu usage,so wanted to check if that can be checked from system side (i.e why process took higher cpu during that particular time) or it should be checked from application team...