Re: Abysmal scheduler performance in Linus' tree?

[Peter Zijlstra]

On Wed, Sep 06, 2017 at 11:03:33AM +0200, Peter Zijlstra wrote:
> On Wed, Sep 06, 2017 at 01:59:14AM -0700, Andy Lutomirski wrote:
> > > Any specifics on your setup?
> > 
> > On further fiddling, I only see this after a suspend and resume cycle.
> 
> Ah, ok. That's not something I otherwise test. Lets see if I can force
> this brick of mine through a suspend-resume cycle :-)

I'd be suspicious of these here commits:

  77d1dfda0e79 ("sched/topology, cpuset: Avoid spurious/wrong domain rebuilds")
  09e0dd8e0f2e ("sched/topology: Avoid pointless rebuild")
  bbdacdfed2f5 ("sched/debug: Optimize sched_domain sysctl generation")

I tested them with regular hotplug, but suspend resume always is a tad
funny.