Hi Peter, On Mon, May 12, 2014 at 10:47 AM, Peter Zijlstra <[email protected]> wrote: > On Mon, May 12, 2014 at 08:53:59AM +0200, Michael Kerrisk (man-pages) wrote: >> On 05/11/2014 04:54 PM, Michael Kerrisk (man-pages) wrote: > >> > $ time sudo ./t_sched_setattr d 18446744072 18446744072 18446744073 >> >> I realize my speculation was completely off the mark. time(2) really >> is reporting the truth, and the sched_setattr() call returns immediately. >> But it looks like with these settings the deadline scheduler gets itself >> into a confused state. The process chews up a vast amount of CPU time >> for the few actions (including process teardown) that occur after >> the sched_setattr() call, and since the SCHED_DEADLINE process has >> priority over everything else, the system locks up. > > Yeah, its doing something weird alright.. let me see if I can get > something useful out.
Thanks! > Btw, you do know about EX_USAGE from sysexits.h ? Yes, I'm peripherally aware of them, but have tended to avoid them because they're not in POSIX, and don't seem to be all that widely used. Cheers, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
