What is the difference between -Xss and -XX:ThreadStackSize?

Question

I just want to control the stack size for all of my threads in a Java (groovy) application. For the Hotspot Oracle VM, I know that there are two parameters doing that (-Xss and

Answer 1

-Xss is an alias for -XX:ThreadStackSize both for OpenJDK and Oracle JDK.

Though they parse arguments differently:
-Xss may accept a number with K, M or G suffix;
-XX:ThreadStackSize= expects an integer (without suffix) - the stack size in kilobytes.