Messages in this thread | | | Date | Mon, 7 Apr 2014 09:41:14 +0530 | Subject | Re: [PATCH V2 0/8] cpusets: Isolate CPUs via sysfs using cpusets | From | Viresh Kumar <> |
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Hi Mike,
On 6 April 2014 14:00, Mike Galbraith <umgwanakikbuti@gmail.com> wrote: > I wonder if adding a quiesce switch is really necessary. > > Seems to me that if you don't have load balancing turned off, you can't > be very concerned about perturbation, so this should be tied into the > load balancing on/off switch as an extension to isolating cores from the > #1 perturbation source, the scheduler.
Its more about not doing any background activities on these CPU which can be avoided. So, even if a add_timer() is issued from these isolated CPUs, it should goto the set chosen for doing background activity, unless add_timer_on() has been issued, in which case user wants that code to execute on the isolated core.
Probably, yes, people would be disabling load_balancing between these cpusets to avoid migration of tasks to isolated core as well.. Atleast we are using it :)
> I also didn't notice a check for is_cpu_exclusive() at a glance, which > would be a bug, but one that would go away if this additional isolation > were coupled to the existing isolation switch.
Yeah, there is no check for that. But I didn't got your point completely. Why do I need to check for exclusivity on the isolated CPUs? So, that same CPU isn't isolated as well as non-isolated on two separate sets?
Thanks for your feedback.
-- viresh
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