Re: [PATCH v4 1/6] x86,sched: Add support for frequency invariance

Qais Yousef
2019-12-19T10:48:21Z

Hi Doug

On 11/28/19 14:48, Doug Smythies wrote:
> Summary: There never was an issue here.
>
> Sorry for the noise of this thread, and the resulting waste of time.
>
> On 2019.11.26 23:33 Doug Smythies wrote:
> > On 2019.11.26 07:20 Giovanni Gherdovich wrote:
> >> On Mon, 2019-11-25 at 21:59 -0800, Doug Smythies wrote:
> >>> [...]
> >>> The issue with the schedutil governor not working properly in the 5.4 RC series
> >>> appears to be hardware dependant.
>
> No it 's not.
>
> Issues with my Sandy Bridge, i7-2600K, test computer and kernel 5.4
> seem to be because it is running an older Ubuntu server version,
> apparently somewhat dependant on cgroup V1 and their cgmanager package.
> I am unable to remove the package to test further because I do use VMs
> that seem to depend on it.
>
> In the kernel configuration when CONFIG_UCLAMP_TASK_GROUP=y
> the computer behaves as though the new parameter "cpu.uclamp.min"
> is set to max rather than 0, but I can not prove it.

I just noticed this. This option shouldn't cause any problem, if it does there
might be a bug that we need to fix.

So cpu.uclamp.min reads 0 but you think it's not taking effect, correct?

In the quotes above I see 5.4 RC, if you haven't tried this against the final
5.4 release, do you mind trying to see if you can reproduce? Trying 5.5-rc2
would be helpful too if 5.4 fails.

Thanks

--
Qais Yousef