System Memory Increases by 7% at 01:30

[Simon P White]

We are running HP-UX 11.11 and recently added extra memory into 4 servers. We have monitored system memory and on all 4 servers the amount used increased by 7% at 01:30. We have checked cron, accounting and perfview but can't find anything that kicks off around this time. The system memory has stayed 7% higher since 01:30. Does anyone have any ideas what may have caused this or how to find out?

[Jitesh purohit_1]

You can use a kmeminfo tool, This does not comes by default with OS, Its a HP Daignostic tool , You can get the latest version from

http://forums11.itrc.hp.com/service/forums/questionanswer.do?admit=109447626+1245746460034+28353475&threadId=1048211

Thanks
Jitesh

[Venkatesh BL]

What about other metrics - like CPU, FS, DISK etc? Do you see fluctuation in those as well?

[Aneesh Mohan]

Hi Simon,

Are there any backup schedules at 1:30?

You can find the list of new process with high memory consumption by executing the below commands after and before 1:30.

#UNIX95=1 ps -e -o vsz,ruser,uid,pid,args |sort -rnk1 |more

Regards,
Aneesh

[Simon P White]

System CPU did increase from 6% to 10% and went back down to 6% afterwards. No backups run on these servers.

[Aneesh Mohan]

Any messages in syslog or mail at 1:30 ?

Any database/application house keeping jobs are executing on those servers ?

If there is no inputs then I feel better you can compare process lists taken before and after 1:30.

Regards,
Aneesh

[Simon P White]

I have run the kmeminfo tool on all 4 servers. Would the static part of the system memory be expected to increase. If so why would this increase? I'm just wondering if we have a kernel parameter set incorrect. The only kernel parmater we changed after the memory upgrade (from 4Gb to 8Gb) was max_dbc_pct which we halved.

We are seeing the same behaviour on all 4 servers even though 3 are running as standby (basically running at 1% CPU) and the other is duty (running at 65% CPU).

[Venkatesh BL]

> System CPU did increase from 6% to 10% and went back down to 6% afterwards

Then something has happened for sure. The thing is if an existing or new process utilizes more memory, that memory is not immediately freed back to the system if there is no memory pressure on the system.

[Jitesh purohit_1]

Hi Simon,

Please can you check the following

1)Are you running any Oracle/Sybase/Informatica Applicatins, which uses more amount of system resources, if so then did you have done any changes int the past in Application, OS.

2) Does the high system utilization , are you seeing any performance issues, Its always not necessary , if your system is using more resources, you should have a performance issues

Thanks
Jitesh

[Simon P White]

The duty server is running Oracle, the other 3 are not running any application. We are not experiencing any performance issues. We plan to increase various parameters within Oracle but the extra memory has already started getting used.