Re: [tip:sched/core] sched/isolation: Document the isolcpus= flags

From: Mike Galbraith
Date: Fri Oct 27 2017 - 10:40:01 EST


On Fri, 2017-10-27 at 15:58 +0200, Peter Zijlstra wrote:
> On Fri, Oct 27, 2017 at 05:06:25AM -0700, tip-bot for Frederic Weisbecker wrote:
> > + isolcpus= [KNL,SMP] Isolate a given set of CPUs from disturbance.
> > + Format: [flag-list,]<cpu-list>
> > +
> > + Specify one or more CPUs to isolate from disturbances
> > + specified in the flag list (default: domain):
> > +
> > + nohz
> > + Disable the tick when a single task runs.
> > + domain
> > + Isolate from the general SMP balancing and scheduling
> > + algorithms. This option is the preferred way to isolate
> > + CPUs from tasks.
>
> I _strongly_ object to this statement, isolcpus is _not_ the preferred
> way, cpusets are.
>
> And yes, while cpusets suffers some problems, we _should_ really fix
> those and not promote this piece of shit isolcpus crap.

+1, isolcpus is the dinosaur that just won't frickn' die.

-Mike