I saw that Squirrel was using a lot of CPU when idle. I ran it through the
YourKit profiler and collected some metrics. Here's the spoiler:
Squirrel's status bar with the Clock + Memory graph is the offending code.
If you disable the status bar in preferences, CPU usage drops to 0.2% from
14%. I checked this on both Mac JDK 6 and Oracle JDK 7 with Ivy Bridge.
I recommend killing the clock -- it merely calls repaint() every second and
everybody has one...
As for the heap usage -- also recommend off by default. End users don't
know what garbage collection is.
Thanks for a great tool, btw. I've used it for years. YourKit gets a big
thumbs up from me, too.