I noticed a fairly big difference in the JVM arguments used when creating containers in Fabric.

My root container runs with

-server -Xms512M -Xmx1024M -XX:+UnlockDiagnosticVMOptions -XX:+UnsyncloadClass -XX:PermSize=128M -XX:MaxPermSize=256M

A child container only runs with

-server

An ssh container uses

-XX:+UnlockDiagnosticVMOptions -XX:+UnsyncloadClass 

What this means:

• Neither child nor SSH container set -Xmx
• Neither child nor SSH set -XX:MaxPermSize
• SSH container does not use -server, hence defaults to client JVM
• child container does not set -XX:+UnlockDiagnosticVMOptions -XX:+UnsyncloadClass, which I thought was needed to work around some dead lock in Karaf.

I really think an

• SSH container should run with -server at the least.
• child and SSH container should explicitly set -Xmx
• child and SSH container should also set -XX:MaxPermSize