I have Ubuntu 19.04 with all updates installed with Intel i9 9900k processor and Asrock H370M pro4 motherboard, it's updated to the latest bios.
I cannot make Turbo boost work for single thread loads (Which I have plenty of and boost in Ghz would be very helpful) If I run some inherently single thread load (and can confirm that only one core being loaded), for example:
sysbench --threads=1 --time=1000 --test=cpu run
I see all cores jump to 4.7Ghz. I expect the core that is under 100% load should jump to 5.0ghz
I have turbo boost enabled:
$ cat /sys/devices/system/cpu/intel_pstate/no_turbo
0
(if I disable it processor speed won't rise above 3.7)
I've read that sometimes some tools doesn't report accurate frequency and in fact turbo boost may work - I've tried multitude of tools with neither reported any different (all cores maxed at 4.7 doing single thread load).
turbostat for example correctly identifies turboboost parameters:
cpu1: MSR_IA32_POWER_CTL: 0x003c005d (C1E auto-promotion: DISabled)
cpu1: MSR_TURBO_RATIO_LIMIT: 0x2f2f2f3030313232
47 * 100.0 = 4700.0 MHz max turbo 8 active cores
47 * 100.0 = 4700.0 MHz max turbo 7 active cores
47 * 100.0 = 4700.0 MHz max turbo 6 active cores
48 * 100.0 = 4800.0 MHz max turbo 5 active cores
48 * 100.0 = 4800.0 MHz max turbo 4 active cores
49 * 100.0 = 4900.0 MHz max turbo 3 active cores
50 * 100.0 = 5000.0 MHz max turbo 2 active cores
50 * 100.0 = 5000.0 MHz max turbo 1 active cores
Still, under single thread load it also shows that all cores are at 4.7Ghz despite only single one is loaded:
$cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_cur_freq
4815705
4721193
4799105
4772830
4794879
4782198
4891662
4714048
4749921
4737188
4801009
4859085
4734327
4735355
4747906
4826031
There is no setting in bios to make all cores always work at max speed (no core optimization or anything remotely related to cores), I've tried to played with all possible settings with no change.
I've tried to change cpu governor to performance with no effect - only all cores are constantly locked at 4.7 instead of on demand.
What's interesting, if I disable cores with
echo 0 | sudo tee /sys/devices/system/cpu/cpu1/online
and leave only 2 cores online - they do in fact reach 5.0 Ghz but that's definitely not a sustainable solution.
Please advise what can else be done
Thank you in advance!
