Error occurred during initialization of VM Could not reserve enough space for object heap

O “Error occurred during initialization of VM Could not reserve enough space for object heap” é comum na inicialização do Tomcat 7 com JDK 7 no Linux 64 bits.
No console pode-se conferir a mensagem:

Error occurred during initialization of VM
Could not reserve enough space for object heap

Para resolver o problema com a alocação de memória, execute o comando:

export _JAVA_OPTIONS=”-Xms20m -Xmx64m -XX:MinHeapFreeRatio=20 -XX:MaxHeapFreeRatio=40 -XX:NewSize=10m -XX:MaxNewSize=10m -XX:SurvivorRatio=6 -XX:TargetSurvivorRatio=80 -XX:+CMSClassUnloadingEnabled -XX:+CMSPermGenSweepingEnabled”