Enterprise Manager and the disadvantages of WLS' Dynamic Monitoring Service (lots of metricdump files)

Had an interesting problem this morning with a customers Windows Server where Enterprise Manager 12c is running: Disk C: - where the EM Software is installed - was full. By the way: Imho, oracle software should never ever be installed in C: ...

The Problem:

Reason for the full disk was Weblogic's Dynamic Monitoring Service (or a weak housekeeping tool ;-)).
Explained:
Weblogic has a feature, called DMS, which is checking some domain metrics and saves them to a file in directory (DOMAIN_HOME/server/<ServerName>/logs/metrics) for each managed server. Each file is about 600 to 800k in size, which is not that much - except You have thousands of those files. Filename is, by the way, somewhat like metricdump*. The files are created per default in a 3 hour cycle.

The Solution:

For this customer's system, I decided to stop the Dynamic Monitoring Service for the AdminServer as well as for the EMGC_OMS1 managed server. To achieve this, search for the file dms_config.xml (DOMAIN_HOME/config/fmwconfig/servers/<ServerName>) and change the value of 'enabled' to "false"

<dumpConfiguration>

  <dump intervalSeconds="10800" maxSizeMBytes="75" enabled="false"/>

</dumpConfiguration>




Restart EM to activate the change. 

Another option could be, to change the value of intervalSeconds to a higher value - for example once a day (86'400 secs) or twice a day (43'200 secs). Or, in case you have a proper working housekeeping tool running each day, configure it that it deletes all files older than 'whatever-you-might-think'.