Java using up far more memory than allocated with -Xmx

Question

I have a project I\'m writing (in Java) for a class where the prof says we\'re not allowed to use more than 200m I limit the stack memory to 50m (just to be absolutely sure)

Answer 1

Max memory = [-Xmx] + [-XX:MaxPermSize] + number_of_threads * [-Xss]

here max heap memory as -Xmx ,min heap memory as -Xms,stack memory as -Xss and -XX maxPermSize

The following example illustrates this situation. I have launched my tomcat with the following startup parameters:

-Xmx168m -Xms168m -XX:PermSize=32m -XX:MaxPermSize=32m -Xss1m