Re: Please backport de53fd7aedb1 : sched/fair: Fix low cpu usage with high throttling by removing expiration of cpu-local slices

[Greg KH <greg@kroah.com>]

On Wed, Sep 25, 2019 at 12:53:48AM -0500, Dave Chiluk wrote:
> Commit de53fd7aedb1 ("sched/fair: Fix low cpu usage with high
> throttling by removing expiration of cpu-local slices") fixes a major
> performance issue for containerized clouds such as Kubernetes.
> 
> Commit de53fd7aedb1 Fixes commit : 512ac999d275 ("sched/fair: Fix
> bandwidth timer clock drift condition").
> 
> This should be applied to all stable kernels that applied commit
> 512ac999d275, and should probably be applied to all others as well.

As this commit isn't in a released kernel just yet, we should wait to
see what happens when it hits people's machines, right?

Also, always cc: all of the people involved in the patch you are asking
for, so as to get their opinion.  For some reason this patch did not
have a cc: stable tag on it, was that because the developers did not
think it was relevant for stable kernels?

> The issues introduced by these pathes can be read about on the
> Kubernetes github.
> https://github.com/kubernetes/kubernetes/issues/67577
> 
> It may also be prudent to also apply the not yet accepted patch that
> fixes some introduced compiler warnings discussed here.
> https://lkml.org/lkml/2019/9/18/925

So we should wait for this to hit Linus's tree too, right?

thanks,

greg k-h