I am on dual core C2D processor, Windows 7 (although this behavior is the same in all MS OSes I've seen). When I run any single threaded CPU-intensive task, it does not stick to 1 core, but rather randomly occupy some 50% of first core, and some 50% on second.
Why they do that? Doesn't that lead to lowering efficiency of L1 cache?
I know that I can set process affinity, I am just wondering the reasouns of such behavior.