Have a feeling this is not a Processing question per se but figure I'll try it out here anyway.

Any guesses as to what makes my app mysteriously slow down more and more as it runs.. and then after several hours, speed back up to full speed again? There's nothing cyclical like that in the code, it just displays a video camera feed all the time.

This has happened three times now, in three successive days of round-the-clock testing. The slowdown lasts for some hours.

Here's the weird part.. if I look at the CPU usage in Task Manager, when the app is running too -slow- it's only using around 50% of CPU, with "System Idle Process" the other 50%. When the app is -fast-, it's using around 95% of CPU. This is Windows XP.

According to Task Manager, javaw's memory usage isn't increasing dramatically. It goes up or down 300k but is around 39mb all the time.

So what could be causing the slowdown? I guess it could be the video camera just not providing new frames on time (because it doesn't feel like it? since the processor seems to have cycles available); or some other process like Windows Update that's coming to life (every day for hours on end?), hidden in "System Idle Process", and taking priority away from my app. I'm not really a Windows person, is it possible for things to hide within "System Idle Process"? Is there a trick to giving my app a higher priority?

Thanks for any advice as to how to troubleshoot this sort of thing,
Dan