I'm using build 135.480 on Ubuntu 12.4. IntelliJ seems great when it works, but it seems to be rather fragile. I find that several times / day I have to restart the IDE, as it hangs doing background tasks. As I write this there is a hang during Make on "Executing pre-compile tasks...", and I often also get hangs during "Writing classes..." that force a restart. In some cases, the GUI remains responsive to input commands, in other cases, not so much.
I have dumped the threads during this current background task, which I've attached. I'm hoping someone can help me debug what's happening. If you have a few minutes to help, I appreciate your time.