Re: [RFC PATCH 4/4] sched: Upload nohz full CPU load on task enqueue/dequeue

[Peter Zijlstra]

On Wed, Jan 20, 2016 at 06:21:07PM +0100, Frederic Weisbecker wrote:

> You mean a periodic call to the above from the housekeepers?
> 
> I didn't think about doing that because you nacked that approach with
> scheduler_tick(). This isn't much different.

This does _one_ thing, namely load accounting. scheduler_tick() does a
whole bunch of things, some which really do not make much sense to do
remotely.

> It means the housekeeper is entirely dedicated to full dynticks CPUs.

Depends on how many there are, and how many housekeepers. I would
suggest one housekeeper cpu per node or so to make sure this keeps
working.

Then again, these load values aren't super important, esp. not for the
nohz_full case where you typically don't care about load balancing.