Re: [sched/fair] fcf0553db6: netperf.Throughput_Mbps -30.8% regression

[Ingo Molnar]

* Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:

> On Sun, Oct 04, 2020 at 05:21:08PM +0100, Mel Gorman wrote:
> > On Sun, Oct 04, 2020 at 09:27:16PM +0800, kernel test robot wrote:
> > > Greeting,
> > > 
> > > FYI, we noticed a -30.8% regression of netperf.Throughput_Mbps due to commit:
> > > 
> > > 
> > > commit: fcf0553db6f4c79387864f6e4ab4a891601f395e ("sched/fair: Remove meaningless imbalance calculation")
> > > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master
> > > 
> > 
> > This commit was the start of a series that made large changes to load
> > balancing.  The series was not bisect-safe and has since been reconciled
> > with the NUMA balancing. Any workload with a potential load balancing
> > problem has to be checked against the latest kernel to see if the problem
> > persists there. If it does, then tip/sched/core should be checked or
> > 5.10-rc1 when it comes out as tip has a few more LB changes pending.
> 
> What Mel said ;-)

Basically it would be nice to test either the following commit directly 
(which is the latest relevant sched/core commit):

   233e7aca4c8a: ("sched/fair: Use dst group while checking imbalance for NUMA balancer")

Or a -next version that includes these commits.

Thanks,

	Ingo