Thank you,
Good to know. But I execute more than 30.000 commands in a loop and that floods the JVM anyway.
I chose a different path. I add all the commands to a list and only process 8 at a time. I use a timer to check every 100ms to check if I any of the 8 command is finished and execute a new one if possible. This is good enough for what I need.
Thanks again.