Do 2 java processes share JVM

Question

Say I run 2 java processes in a machine, do they share JVM or they have their own separate JVM. I remember setting something like export JVM_OPTS="-Xms64m -Xmx1024m"

then which JVM is this for?

Answer 1

They have their own separate JVM.
If you export JVM_OPTS, the variable affects all JVMs reading that value.
If you want to share JVM among different computations you must use multithreading.