A couple a days ago we had a client contact us and ask us to take a look as their Oracle Cloud Control 12c. They were having issues with a few targets that were reporting as being down on one screen and up on another.
We logged into the server and tried to run ./emctl status oms and we recieved the below error.
Oracle Enterprise Manager Cloud Control 12c Release 184.108.40.206.0
Copyright (c) 1996, 2011 Oracle Corporation. All rights reserved.
Error occurred during initialization of VM
Could not reserve enough space for object heap
This error is usually asscioated with a memory issue. A quick look at the memory usage on the server quickly showed us an issue with low memory. We noticed that the opmn process was consuming 31.9GB of 32GB of RAM. We knew this was extremely high because there isn’t anything besides the Cloud Control loaded on this server. We noticed this by using top. The commands below will show you processed sorted by RAM usage.
>press ‘n’ and enter
Once we found what process was consuming all the memory we simply restarted the process. We were lucky it was opmn because we can use opmnctl to stopall and startall without having to reboot the whole box. After that was done the targets reporting to be down before now showed up and available.
I hope this quick blurp helps someone else quickly identify and fix a run away process.