Setting the following environment variable before starting your application, you can increase them easily.
Unix
export JAVA_OPTS="-Xms512m -Xmx1024m -XX:MaxPermSize=1024m"
Windows
set JAVA_OPTS="-Xms512m -Xmx1024m -XX:MaxPermSize=1024m"
export JAVA_OPTS="-Xms512m -Xmx1024m -XX:MaxPermSize=1024m"
set JAVA_OPTS="-Xms512m -Xmx1024m -XX:MaxPermSize=1024m"
set JPDA_ADDRESS=8000 set JPDA_TRANSPORT=dt_socket bin/catalina.bat jpda start
export JPDA_ADDRESS=8000 export JPDA_TRANSPORT=dt_socket bin/catalina.sh jpda start