Network Management / (OpenView-NNM) Practitioners Forum

The memory region 'PS Old Gen' is at 95.17% usage.

Nestor Herrera
Frequent Visitor

The memory region 'PS Old Gen' is at 95.17% usage.

Hello Team

I presented a NNMi alert:

The memory region 'PS Old gene' is at 95.17% usage.

the increase in the memory in the file and parameter ‑Xmx already registered, but the problem persists occasionally.

Any ideas?


Best regards


Re: The memory region 'PS Old Gen' is at 95.17% usage.

Hello Nestor,


Beyond the obvious suggestion to improve physical memory, I did some changes in NNMi 9.1x to optimize memory usage that could help you:


1. Change the relation between old and young gen:




2. Set the same value to -Xms and -Xmx to minimize the overhead to allocate memory. For instance:





3. Set the -Xms and -Xmx to use the maximum memory available excluding 1-2GB for OS and 2-4GB for DB. Only with some time of monitoring is possible to define the best configuration for your system.


This recomendations are based in Oracle Java Documentation and empirical tests.


To monitoring JVM memory utilization, you can use jconsole tool. Please see the link below for more details:



Hope this helps,



“The greatest challenge to any thinker is stating the problem in a way that will allow a solution.”
Bertrand Russell

Re: The memory region 'PS Old Gen' is at 95.17% usage.

There are a few reasons this may happen.

I would recommend opening a support case for this (if this high utilization behavior has persisted for a while).


You could take a look at the trend of this behavior in the health.logs ($NNMDataDir/logs/nnm/).


These logs, in conjunction with the jbossServer.logs (or nnm.logs for version 9.2x) could point to a more specific problem as the root cause of such behavior.


It would also be helpful to know the NNMi version and patch info (nnmversion.ovpl).


And as far as troubleshooting PS Old Gen issues go, the most recent health report (nnmhealth.ovpl -print verbose > someTextFile.txt) would help.

Mohit Sharma,
HP Software Support

The views expressed in my contributions are my own and do not necessarily reflect the views and strategy of HP.

If you find this or any post resolves your issue, please be sure to mark it as an accepted solution.
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