How would one receive notification (signal or otherwise) that the current thread is about to be or was just swapped out and that the current thread is about to be or was just swapped back in? With present compilers and the PPC RTC register "active" profilers are a real possibility. But, to make them robust on a preemptive multi-cpu OS the question above must be resolved. I've thought about instrumenting semaphore and mutex abstractions and finding and instrumenting the time slice expired signal. To be generally useful, all calls that would likely block the current thread (read, write, accept, glFlush, etc, etc) would have to be instrumented. But these all just seem like problematic hacks that avoid finding the real solution. Is there an exposed relatively hi-level way in the shipping kernel to do this? If not, any pointers on where to look in the kernel? -- Jonathan Hess ViviStar Consulting http://www.vivistar.com/ mailto:jahess@vivistar dot com _______________________________________________ darwin-kernel mailing list | darwin-kernel@lists.apple.com Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/darwin-kernel Do not post admin requests to the list. They will be ignored.