As of raising this question, Docker looks to be new enough to not have answers to this question on the net. The only place I found is this article in which the author is saying it is hard, and that's it.
Note that in a docker-compose.yml
file - you'll need to leave out the double-quotes:
environment:
- JVM_OPTS=-Xmx12g -Xms12g -XX:MaxPermSize=1024m
or
environment:
- CATALINA_OPTS=-Xmx12g -Xms12g -XX:MaxPermSize=1024m