Re: sched_rt_period_timer causing large latencies

[Mike Galbraith]

On Thu, 2018-04-05 at 10:27 +0200, Peter Zijlstra wrote:
> On Thu, Apr 05, 2018 at 09:11:38AM +1000, Nicholas Piggin wrote:
> > Hi,
> > 
> > I'm seeing some pretty big latencies on a ~idle system when a CPU wakes
> > out of a nohz idle. Looks like it's due to the taking a lot of remote
> > locks and cache lines. irqoff trace:
> 
> On RT I think we default RT_RUNTIME_SHARE to false, maybe we should do
> the same for mainline.

Probably.  My very first enterprise encounter with the thing was it NOT
saving a box from it's not so clever driver due to that.

	-Mike