Celeron J3160 with enabled Turbo mode stays at 480MHz(lowestsetting) forever and can not lower frequency without Tuebo mode

[Lev Serebryakov]

On 05.09.2018 17:51, Cy Schubert wrote:

> I don't think you need something accurate.
 Ok, here is results. I'm working in single-user mode.

 TL;DR "Turbo" mode make "openssl" much slower (x3.5)!

 I can not properly interpret this result.

 But "turbostat" properly detect Turbo/No-Turbo mode, so it is not
mistake in BIOS.

(1) Trubo ENABLED, powerd IS NOT started

  dev.cpu.0.freq=480 no matter what.

  turbostat shows DIFFERENT speeds, like this (I've removed IRQ-related
fields to fit in one line):

Package Core CPU Avg_MHz Busy% Bzy_MHz TSC_MHz CPU%c1 CPU%c3 CPU%c6
-       -    -   2       0.30  1359    1600    6.18   0.00   93.52  31
0       0    0   2       0.36  863     1600    0.08   0.00   99.56  31
0       1    1   4       0.47  1462    1600    24.56  0.00   74.96  31
1       0    2   2       0.22  1670    1600    0.05   0.00   99.72  29
1       1    3   2       0.14  1792    1600    0.02   0.00   99.84  29

 "openssl speed aes-256-cbc":

type        16 bytes     64 bytes    256 bytes   1024 bytes   8192 bytes
aes-256 cbc 5653.98k     6159.49k     6356.31k    17271.70k    17517.23k

(2) Trubo ENABLED, powerd IS started

  dev.cpu.0.freq shows different values, from 60 in idle to 1601 under load.

 turbostat shows same values, but at idle Bzy_MHz drops low.

 openssl is the same

type        16 bytes     64 bytes    256 bytes   1024 bytes   8192 bytes
aes-256 cbc 5580.78k     6155.97k     6349.23k    17273.51k    17511.77k

(3) Trubo DISABLED, powerd IS NOT started

  dev.cpu.0.freq=1600 no matter what.

  turbostat shows higher numbers:

Package Core CPU Avg_MHz Busy% Bzy_MHz TSC_MHz CPU%c1 CPU%c3 CPU%c6
-       -    -   2       0.21  1807    1600    1.44   0.00   98.35   38
0       0    0   3       0.28  1764    1600    0.06   0.00   99.66   38
0       1    1   3       0.24  2052    1600    1.72   0.00   98.03   38
1       0    2   1       0.09  1629    1600    0.02   0.00   99.89   36
1       1    3   2       0.22  1664    1600    3.94   0.00   95.84   36

 "openssl speed aes-256-cbc":

type        16 bytes     64 bytes     256 bytes   1024 bytes   8192 bytes
aes-256 cbc 18939.95k    20638.71k    21281.24k    57836.36k    58736.39k

 (3.5 times faster that with Turbo ENABLED!)

(4) Trubo DISABLED, powerd IS started

  dev.cpu.0.freq shows different values, from 60 in idle to 1600 under load.

 turbostat shows very low Bzy_MHz on idle, but high (suspiciously high)
under load:

Package Core CPU Avg_MHz Busy% Bzy_MHz TSC_MHz  CPU%c1 CPU%c3 CPU%c6
-       -    -   1475    92.22 2666    1600     1.66   0.00   6.12    41
0       0    0   1475    92.22 2666    1600     1.62   0.00   6.16    41
0       1    1   1475    92.21 2666    1600     1.41   0.00   6.38    41
1       0    2   1475    92.21 2666    1600     1.78   0.00   6.01    38
1       1    3   1476    92.24 2666    1600     1.84   0.00   5.92    38


 openssl is almost the same

type        16 bytes     64 bytes    256 bytes   1024 bytes   8192 bytes
aes-256 cbc 16277.18k    20620.71k    21272.10k    57998.35k    58687.83k

-- 
// Lev Serebryakov