Agent Performance

A friend writes:

"Do you have any tips for keeping the emagent from making a bad situation worse. For instance when everything is working well emagent hardly takes any CPU or memory, but once the host or db's start getting a high load emagent seems to start using more CPU than just about anything else. It's kind of counter intuitive to me, that something designed to monitor and notify you about problems actually becomes the problem when a server becomes short on resources."

My response:

One point to remember is that you should always upgrade to the latest version of the agent. For eg. If your central OMS is on EM11g, then your agents should also be EM11g agents and not EM10g agents. Upgrading to the latest version at the agent level will also fix some performance issues for the agent.

The issue you describe happens when there is a contention for resources at both sides. Make sure the agent is properly configured, it has enough free disk space to store its temporary work, etc. Remember the agent pre-requisites should always be followed - for eg, if you install the EM 10g agent on a box running Oracle 9i, you must ensure the OS is patched etc upto the level required if you were installing an Oracle 10g database on the same box. All such pre-requisites for an Oracle 10g database should be followed in such a case.

Many times the prerequisites are not followed, and the agent then struggles to perform on the older boxes since the OS is not patched to the level required, some packages are older than the requirement, swap space is lower than required, etc. Then, there are performance issues. So please check the setup first.