Quote Originally Posted by 'Clanked',index.php?page=Thread&postID=159047#post 159047
Please correct me if I have 0 grasp of whats going on, but it sounds to me like they are doing this...
We can open Task Manager and look at the CPU graphs and see what they're doing. For example, the PC I'm using has two physical cores and it's extremely lightly loaded (overall about 2 percent) but even so, the graphs show that the scheduler is dividing the load between the two cores. If you check your own PC, I think you'll find the same thing under most conditions.

100% usage is only a problem if something is not getting done, due to not being able to get its cycles completed. If those cycles are handed to another core, is there a problem?
Yes but the scheduler isn't only concerned with avoiding problems. It's designed to maximize performance. It's not good enough that everything gets done. The goal is to get everything done as quickly as possible. This means minimizing the amount of time that threads have to wait before they can run, etc.