Intermittent Login issue R12.1 - 500 Internal Server Error

Problem Description:

Users are unable to get application login page.

Users are frequently getting below error while accessing the EBS application URL.

Cause:

This issue occurred due to low oacore heap size.

Solution:

Increase the oacore heap size and restart application services.

Change the parameters in $ORA_CONFIG_HOME/10.1.3/opmn/conf/opmn.xml

of both form nodes as shown below:

From:

-Xmx512M -Xms128M -XX:MaxPermSize=160M

To:

-Xmx1536M -Xms128M -XX:MaxPermSize=160M

Reference:

JVM: Guidelines to setup the Java Virtual Machine in Apps E-Business Suite 11i and R12 (Doc ID 362851.1)