Enterprise Manager 13c – Change Memory Settings with emctl

In Enterprise Manager Grid Control 11g, changes in the Oracle Management Server JVM memory settings could be done in a file called startEMServer.sh located in a domain subdirectory like /u00/app/oracle/product/gc_inst/user_projects/domains/GCDomain/bin/

And after an OMS restart, the JVM has used this new settings for the OMS.  Since 12c, it can be done by an emctl command.

emctl – Get your actual Settings OMS_HEAP_MAX

emctl – Change the Value

For example, the Memory will be resized to 2304M.

Verification

Restart your Oracle Management Server. In one of my tests this did not work. The OMS still used the old memory value. Another start/stop with emctl stop oms -all has worked.

The new value is now active:

In Linux, you can search for the java process with ps -ef | grep “java -server -Xms256M -Xmx”  – here are the first lines from my output where the Xmx parameter is located:

As you can see, the -Xmx Parameter is now set to 2304M, the Java virtual machine for EMGC_OMS1 is now using 2304M.

Link

Enterprise Manager Cloud Control Advanced Installation and Configuration Guide – Sizing Your Enterprise Manager Deployment