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

From: Ingo Molnar
Date: Fri Oct 27 2017 - 13:06:41 EST



* 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,

Ingo