Re: [RFC PATCH v2 00/17] Core scheduling v2

From: Ingo Molnar
Date: Mon Apr 29 2019 - 02:14:32 EST



* Li, Aubrey <aubrey.li@xxxxxxxxxxxxxxx> wrote:

> > I suspect it's pretty low, below 1% for all rows?
>
> Hope my this mail box works for this...
>
> .-------------------------------------------------------------------------------------------------------------.
> |NA/AVX vanilla-SMT [std% / sem%] | coresched-SMT [std% / sem%] +/- | no-SMT [std% / sem%] +/- |
> |-------------------------------------------------------------------------------------------------------------|
> | 1/1 508.5 [ 0.2%/ 0.0%] | 504.7 [ 1.1%/ 0.1%] -0.8%| 509.0 [ 0.2%/ 0.0%] 0.1% |
> | 2/2 1000.2 [ 1.4%/ 0.1%] | 1004.1 [ 1.6%/ 0.2%] 0.4%| 997.6 [ 1.2%/ 0.1%] -0.3% |
> | 4/4 1912.1 [ 1.0%/ 0.1%] | 1904.2 [ 1.1%/ 0.1%] -0.4%| 1914.9 [ 1.3%/ 0.1%] 0.1% |
> | 8/8 3753.5 [ 0.3%/ 0.0%] | 3748.2 [ 0.3%/ 0.0%] -0.1%| 3751.3 [ 0.4%/ 0.0%] -0.1% |
> | 16/16 7139.3 [ 2.4%/ 0.2%] | 7137.9 [ 1.8%/ 0.2%] -0.0%| 7049.2 [ 2.4%/ 0.2%] -1.3% |
> | 32/32 10899.0 [ 4.2%/ 0.4%] | 10780.3 [ 4.4%/ 0.4%] -1.1%| 10339.2 [ 9.6%/ 0.9%] -5.1% |
> | 64/64 15086.1 [11.5%/ 1.2%] | 14262.0 [ 8.2%/ 0.8%] -5.5%| 11168.7 [22.2%/ 1.7%] -26.0% |
> |128/128 15371.9 [22.0%/ 2.2%] | 14675.8 [14.4%/ 1.4%] -4.5%| 10963.9 [18.5%/ 1.4%] -28.7% |
> |256/256 15990.8 [22.0%/ 2.2%] | 12227.9 [10.3%/ 1.0%] -23.5%| 10469.9 [19.6%/ 1.7%] -34.5% |
> '-------------------------------------------------------------------------------------------------------------'

Perfectly presented, thank you very much!

My final questin would be about the environment:

> Skylake server, 2 numa nodes, 104 CPUs (HT on)

Is the typical nr_running value the sum of 'NA+AVX', i.e. is it ~256
threads for the 128/128 row for example - or is it 128 parallel tasks?

I.e. showing the approximate CPU thread-load figure column would be very
useful too, where '50%' shows half-loaded, '100%' fully-loaded, '200%'
over-saturated, etc. - for each row?

Thanks,

Ingo