Problems with Performance of Oracle Java Cloud Service—Coherence Service Instances

Depending on access patterns and memory usage, an Oracle Java Cloud Service — Coherence instance might show performance problems under a heavy load. You might see long, multi-second garbage collection times on Managed Servers of the Coherence data tier. To address this issue, you can change the garbage collection scheme to CMS.

To change the garbage collection scheme on a Managed Server on the Coherence data tier:

1. Navigate to the Oracle Java Cloud Service Console.
2. Open the Administration Console for your service by selecting it from the drop-down menu.
3. On the Administration Console, under Domain Structure, expand Environment and select Servers.
   The Summary of Servers page is displayed.
4. On the Configuration page, in the Servers table, click the name of a Managed Server of the Coherence data tier.
   The Settings page is displayed.
5. Click the Configuration tab, then the Server Start tab.
6. Click Lock & Edit.
7. In the Arguments pane, add the —XX:+UseConcMarkSweepGC flag to the end of the list.
8. Click Activate Changes.
9. Restart the Managed Server.

   See Use the WebLogic Server Administration Console to Shut Down Servers and Use the WebLogic Server Administration Console to Start Managed Servers.

10. Repeat this process for all Managed Servers of the Coherence data tier.