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

From: Ingo Molnar
Date: Fri Oct 27 2017 - 14:21:54 EST



* Frederic Weisbecker <frederic@xxxxxxxxxx> wrote:

> 2017-10-27 19:06 UTC+02:00, Ingo Molnar <mingo@xxxxxxxxxx>:
> >
> > * Frederic Weisbecker <frederic@xxxxxxxxxx> wrote:
> >
> >> 2017-10-27 15:58 UTC+02:00, Peter Zijlstra <peterz@xxxxxxxxxxxxx>:
> >> > 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.
> >>
> >> I definitely agree with that so your position is a relief :-) This
> >> patch only indented the existing parameter documentation so fixing its
> >> content was beyond its scope. I'll send a patch to correct the text.
> >
> > Since it was the last commit in tip:sched/core that was pushed out just
> > hours ago
> > I zapped that last commit, please send an updated patch which we can apply
> > and get
> > a clean series.
> >
> > Thanks,
>
> Note the issue was there before that patch. But nevermind I'll resend
> an updated version of the patch.

Yeah - so we get a single 'improve documentation' commit.

Thanks,

Ingo