Marc E. Fiuczynski wrote: > Paraphrasing Jens Axboe: > >>I don't think you can compare [plugsched with the plugio framework]. >>Yes they are both schedulers, but that's about where the 'similarity' >>stops. The CPU scheduler must be really fast, overhead must be kept >>to a minimum. For a disk scheduler, we can affort to burn cpu cycles >>to increase the io performance. The extra abstraction required to >>fully modularize the cpu scheduler would come at a non-zero cost as >>well, but I bet it would have a larger impact there. I doubt you >>could measure the difference in the disk scheduler. > > > Modularization usually is done through a level of indirection (function > pointers). I have a can of "indirection be gone" almost ready to spray over > the plugsched framework that would reduce the overhead to zero at runtime. > I'd be happy to finish that work if it makes it more palpable to integrate a > plugsched framework into the kernel? The indirection was a minor point. On modern cpus it was suggested by wli that this would not be a demonstrable hit in perormance. Having said that, I'm sure Peter would be happy for another developer. I know how tiring and lonely it can feel maintaining such a monster. Cheers, Con