Below is the jvm configuration of a tomcat server used to a liferay deployment installation

Options for memory profiling

-Dcom.sun.management.jmxremote
-Dcom.sun.management.jmxremote.port=7009
-Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.authenticate=false

Options for memory optimization
-server

Heap Size (Xms and Xmx is good to have the same value)
-Xms1524m
-Xmx1524m

Young generation size (up to 1/3 of the whole heap)
-XX:NewSize=256m
-XX:MaxNewSize=512m

PermSize (usually small size gives PermGen space)
-XX:PermSize=256m
-XX:MaxPermSize=512m

Garbage Collection
-XX:+UseConcMarkSweepGC (when you have multiple CPUs)
-XX:SurvivorRatio=20