CPU benchmark advice
Why would it use 200%? According to Pavel, different robots can run on different cores, but they are synchronized so only one is running at once, basically capping your actual performance at the speed of one core. So it should be 100% + some JVM / Robocode engine overhead, I'd think.
That overhead happens about 30% of the time, so an instance uses about 130% cores average. But there are peaks of 200%. When I run 3 instances on 4 cores, they use all cores most of the time, but you see one idle core sometimes (and it´s not uploading).
When running test beds, I run one instance per core (and disable turn skipping), so all cores are used all of the time.
Running a benchmark restricting each instance to a single core would remove that parallel overhead.