Graph thread always at 100% CPU

[icetan]

I'm having this issue where just running any mach program spawns a thread that is constantly at 100% CPU.

See the first process in this screenshot of htop:

I traced it to the Graph.processThread function that seems to be busy waiting on operations from the queue.

I made a naive patch that uses a Futex.wait that latches after each time the queue has been emptied and any time something pushes to the queue it wakes to start emptying the queue again.

This is how htop looks after applying the patch: