Re: [REGRESSION] Re: [PATCH 00/24] Complete EEVDF

[Peter Zijlstra <peterz@infradead.org>]

On Mon, Jan 06, 2025 at 05:59:32PM +0100, Peter Zijlstra wrote:
> On Mon, Jan 06, 2025 at 07:01:34AM -0800, Doug Smythies wrote:
> 
> > > What is the easiest 100% load you're seeing this with?
> > 
> > Lately, and specifically to be able to tell others, I have been using:
> > 
> > yes > /dev/null &
> > 
> > On my Intel i5-10600K, with 6 cores and 2 threads per core, 12 CPUs,
> > I run 12 of those work loads.
> 
> On my headless ivb-ep 2 sockets, 10 cores each and 2 threads per core, I
> do:
> 
> for ((i=0; i<40; i++)) ; do yes > /dev/null & done
> tools/power/x86/turbostat/turbostat --quiet --Summary --show Busy%,Bzy_MHz,IRQ,PkgWatt,PkgTmp,TSC_MHz --interval 1
> 
> But no so far, nada :-( I've tried with full preemption and voluntary,
> HZ=1000.
> 

And just as I send this, I see these happen:

100.00  3100    2793    40302   71      195.22
100.00  3100    2618    40459   72      183.58
100.00  3100    2993    46215   71      209.21
100.00  3100    2789    40467   71      195.19
99.92   3100    2798    40589   71      195.76
100.00  3100    2793    40397   72      195.46
...
100.00  3100    2844    41906   71      199.43
100.00  3100    2779    40468   71      194.51
99.96   3100    2320    40933   71      163.23
100.00  3100    3529    61823   72      245.70
100.00  3100    2793    40493   72      195.45
100.00  3100    2793    40462   72      195.56

They look like funny little blips. Nowhere near as bad as you had
though.