Re: [RFC PATCH] tick/sched: Ensure quiet_vmstat() is called when the idle tick was stopped too

[Marcelo Tosatti]

On Thu, Feb 24, 2022 at 01:28:16PM +0000, Aaron Tomlin wrote:
> On Thu 2022-02-24 10:14 -0300, Marcelo Tosatti wrote:
> > If the per-CPU vmstat_update is limited to happen once per second, that
> > shouldnt be a significant performance impact?
> 
> Perhaps not. Albeit, is the interrupt worth it? 

Its a requirement for correctness right?

> Then again it could indeed
> be a long time before the idle task is selected and a return to idle code
> were we'd check for any remaining differentials with the aforementioned
> patch.

Or a long time before userspace returns to kernel.