Re: [PATCH v2] sched/fair: Age the average idle time

[Phil Auld]

On Tue, Jun 15, 2021 at 10:42:28PM +0200 Peter Zijlstra wrote:
> On Tue, Jun 15, 2021 at 12:16:11PM +0100, Mel Gorman wrote:
> > From: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> > 
> > This is a partial forward-port of Peter Ziljstra's work first posted
> > at https://lore.kernel.org/lkml/20180530142236.667774973@xxxxxxxxxxxxx/.
> 
> It's patches 2 and 3 together, right?
> 
> > His Signed-off has been removed because it is modified but will be restored
> > if he says it's still ok.
> 
> I suppose the SoB will auto-magically re-appear if I apply it :-)
> 
> > The patch potentially matters when a socket was multiple LLCs as the
> > maximum search depth is lower. However, some of the test results were
> > suspiciously good (e.g. specjbb2005 gaining 50% on a Zen1 machine) and
> > other results were not dramatically different to other mcahines.
> > 
> > Given the nature of the patch, Peter's full series is not being forward
> > ported as each part should stand on its own. Preferably they would be
> > merged at different times to reduce the risk of false bisections.
> 
> I'm tempted to give it a go.. anyone object?
> 

Fwiw, I have some perf tests running on v1.  But I don't know if the
results will be in before I'm AFK next week. I suppose we could pull
it back out if something really bad comes up.

Seems like a reasonable change to me on the surface.


Cheers,
Phil
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