On Fri, Jul 11, 2014 at 02:05:08PM -0500, Christoph Lameter wrote: > On Fri, 11 Jul 2014, Frederic Weisbecker wrote: > > > > That would imply that all no-nohz processors are housekeeping? So all > > > processors with a tick are housekeeping? > > > > Well, now that I think about it again, I would really like to keep > > housekeeping > > to CPU 0 when nohz_full= is passed. > > Yeah. > > > > Could we make that set configurable? Ideally I'd like to have the ability > > > restrict the housekeeping to one processor. > > > > Ah, I'm curious about your usecase. But I think we can do that. And we > > should. > > The use case is pretty straightforward because we are trying to keep as > much OS noise as possible off most processors. Processor 0 is the > sacrificial lamb that will be used for all OS processing and hopefully all > high latency operations will occur there. Processors 1-X have a tick but > we still try to keep latencies sane. And then there is X-Y where tick is > off.
Ok. I don't entirely get why you need 1-X but I can easily imagine some non-latency-critical stuff running there. Paul proposed "housekeeping=". If we ever go there, I'd rather vote for "sacrifical_lamb=" -- 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/
