Messages in this thread | | | Date | Fri, 11 Jul 2014 14:05:08 -0500 (CDT) | From | Christoph Lameter <> | Subject | Re: [PATCH tip/core/rcu 11/17] rcu: Bind grace-period kthreads to non-NO_HZ_FULL CPUs |
| |
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.
| |