depends on what ur doing..

are you calling Thread.yeild(), Thread.sleep(x), or just an infinite loop?

If ur calling Thread.sleep(x), then it must be something else, If your doing a straight loop, with no timing, then its the programs fault.

If your doing Thread.yeild(), what happens is that your thread moves away from the cpu, giving another thread a chance to come and do its own stuff, and when thats finished, your thread comes back. So in essence, Thread.yeild() is the best way to go. 100% CPU usage is not a bad thing at all!