R12.2 Forms Server Fails With "Could not reserve enough space for object heap" on OEL6

Issue :

Not able to start the forms managed server  with XMX as 2G.

Cause:

It was working fine. No changes has been made.

Solution:

Unlike oacore, Forms servers are running on top of 32 bit JVM. There is a bug (or) limitation on 32 bit libraries  to reserve the memory more than 1G.  Please see the output 32 and 64 bit  java output below.

$COMMON_TOP/util/jdk32/jre/bin/java  -Xms32m -Xmx3072m -XX:MaxPermSize=256m -version

Error occurred during initialization of VM

Could not reserve enough space for object heap

Error: Could not create the Java Virtual Machine.

Error: A fatal exception has occurred. Program will exit.

 $COMMON_TOP/util/jdk64/jre/bin/java  -Xms32m -Xmx3072m -XX:MaxPermSize=256m -version

java version "1.7.0_85"

Java(TM) SE Runtime Environment (build 1.7.0_85-b15)

Java HotSpot(TM) 64-Bit Server VM (build 24.85-b06, mixed mode)

This is caused by the prelink command. It calculates shared library load addresses, and updates the shared libraries with them. Simplest thing to do is to undo what prelink did, and disable it.

By default prelinking is enabled on OEL6 (not receiving this error on OEL7) 

Disable prelink method

To disable prelinking

a. Login as root user & execute prelink -u --all

 b. Edit /etc/sysconfig/prelink and save.

    set PRELINKING=no

c. Now try to execute below command. It should not return any error.

$COMMON_TOP/util/jdk32/jre/bin/java  -Xms32m -Xmx3072m -XX:MaxPermSize=256m -version