On Thu, Dec 15, 2011 at 10:44 AM, Tom Evans <tevans...@googlemail.com> wrote: > Real time scheduler changing would be insane! I was thinking that > both/any/all schedulers could be compiled into the kernel, and the > choice of which one to use becomes a boot time configuration. You > don't have to recompile the kernel to change timecounter.
Right. Switching the scheduler on the fly may be thinkable though. I could imagine a syscall that would suspend all scheduling, convert the bookkeeping data of one scheduler into the other scheduler's, and transfer control to the other scheduler. Of course, that would require some heavy hacking, as I would imagine that "cross-scheduler surgery" would result in a pretty hard to debug kernel (at least during development). A more general solution could even be a separate userland scheduler process a la L4 [*], but since we don't have lightweight IPC in the kernel (yet, or never), it would require even heavier black wizardry. But nice and flexible it would be. ;-) [*] Refs: - https://github.com/l4ka/pistachio - http://www.systems.ethz.ch/education/past-courses/fall-2010/aos/lectures/wk13-scheduling-print.pdf Regards, -cpghost. -- Cordula's Web. http://www.cordula.ws/ _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"
