I am having a small issue which I'm not understanding quite entirely. So basically I have a thread which is waiting on an event and a timeSetEvent from WinMM which is pulsing the event every 1ms.
I put some query performance counter in my thread to find out the the time distance between each thread start. The thread is currently just waiting for the event and checking its own rate and doing nothing else.
I verified that he WinMM is correctly scheduled every 1ms, however, once the event is signaled, sometimes my thread is being preempted and runs ~6ms later than expected. At this point I started playing with priorities and affinity. So i cranked up my priority class to real time and my threads to time critical. And when on core 0 my thread still gets preempted every now and then (~1-2 times every 15 seconds). Instead if I set the affinity to core 2 it never gets preempted (like never ever, I ran the test software for a few hours, never got prempted once). Are there some driver/system threads running with priority above real time/time critical that are bound to core 0 only?
I am running on windows 7 pro on Intel i7-3470.
