userspace cpufreq governor not working as advertised

SUSE Product Topics SLES Hardware
1

Hi,

I am using Suse Linux Enterprise Server 11.2, kernel version 3.0.13-0.27-default.
When I set the cpufreq governor to performance or userspace, the frequency of all the cores does not remain fixed and fluctuates very often. But, this should not be the case. The performance governor should always run the cores at the maximum frequency and userspace governor should run the cores at the user specified frequency.
I think there might be some temperature sensors which are causing the cpu frequency to fluctuate. I have the following modules of interest loaded


acpi_cpufreq 18803 0
processor 44407 1 acpi_cpufreq
thermal_sys 24622 1 processor
cpufreq_userspace 13162 2
cpufreq_powersave 12618 15
cpufreq_conservative 13863 0
mperf 12667 1 acpi_cpufreq

I think the thermal_sys module is causing the cpu frequency to fluctuate, so I want to unload it. To unload thermal_sys, I have to unload acpi_cpufreq. Once I unload acpi_cpufreq, all the interface to read cpu frequency are gone, so I cannot cross-check whether the cpu frequency fluctuates or not
Could you please help me in pointing out the issue

Regards
Rahul

2

rahulshri Wrote in message:
[color=blue]

I am using Suse Linux Enterprise Server 11.2, kernel version
3.0.13-0.27-default.
When I set the cpufreq governor to performance or userspace, the
frequency of all the cores does not remain fixed and fluctuates very
often. But, this should not be the case. The performance governor should
always run the cores at the maximum frequency and userspace governor
should run the cores at the user specified frequency.
I think there might be some temperature sensors which are causing the
cpu frequency to fluctuate. I have the following modules of interest
loaded

acpi_cpufreq 18803 0 processor 44407 1 acpi_cpufreq thermal_sys 24622 1 processor cpufreq_userspace 13162 2 cpufreq_powersave 12618 15 cpufreq_conservative 13863 0 mperf 12667 1 acpi_cpufreq

I think the thermal_sys module is causing the cpu frequency to
fluctuate, so I want to unload it. To unload thermal_sys, I have to
unload acpi_cpufreq. Once I unload acpi_cpufreq, all the interface to
read cpu frequency are gone, so I cannot cross-check whether the cpu
frequency fluctuates or not
Could you please help me in pointing out the issue[/color]

SUSE Linux Enterprise Server 11 SP2 (11.2) is no longer supported,
are you able to try with the latest release, SLES11 SP3?

HTH.

Simon Flood
SUSE Knowledge Partner

3

Hi,

How to upgrade to 11.3 ?
Could you please let me know if there are any patch submitted towards cpufreq. If not, then I don’t see any reason to upgrade it to 11.3. I am happy with the old features with cpufreq working as intended

Regards
Rahul

[QUOTE=smflood;23595]rahulshri Wrote in message:
[color=blue]

I am using Suse Linux Enterprise Server 11.2, kernel version
3.0.13-0.27-default.
When I set the cpufreq governor to performance or userspace, the
frequency of all the cores does not remain fixed and fluctuates very
often. But, this should not be the case. The performance governor should
always run the cores at the maximum frequency and userspace governor
should run the cores at the user specified frequency.
I think there might be some temperature sensors which are causing the
cpu frequency to fluctuate. I have the following modules of interest
loaded

acpi_cpufreq 18803 0 processor 44407 1 acpi_cpufreq thermal_sys 24622 1 processor cpufreq_userspace 13162 2 cpufreq_powersave 12618 15 cpufreq_conservative 13863 0 mperf 12667 1 acpi_cpufreq

I think the thermal_sys module is causing the cpu frequency to
fluctuate, so I want to unload it. To unload thermal_sys, I have to
unload acpi_cpufreq. Once I unload acpi_cpufreq, all the interface to
read cpu frequency are gone, so I cannot cross-check whether the cpu
frequency fluctuates or not
Could you please help me in pointing out the issue[/color]

SUSE Linux Enterprise Server 11 SP2 (11.2) is no longer supported,
are you able to try with the latest release, SLES11 SP3?

HTH.

Simon Flood
SUSE Knowledge Partner[/QUOTE]

4

On 15/09/2014 05:54, rahulshri wrote:
[color=blue]

How to upgrade to 11.3 ?[/color]

https://www.suse.com/documentation/sles11/book_sle_deployment/data/sec_update_sle11sp2.html
[color=blue]

Could you please let me know if there are any patch submitted towards
cpufreq. If not, then I don’t see any reason to upgrade it to 11.3. I am
happy with the old features with cpufreq working as intended[/color]

Well one reason to upgrade is that SLES11 SP2 is no longer supported so
any issues now reported won’t be fixed.

However I’ve just noticed that you reported you were using “kernel
version 3.0.13-0.27-default” - this is the original version that SLES11
SP2 shipped with and not the latest (last) version 3.0.101-0.7.17.1
available (for SLES11 SP2).

Checking the RPM changelog for the original versus latest version I see
references to cpufreq so I’d suggest making sure your SLES11 SP2 is
fully patched.

HTH.

Simon
SUSE Knowledge Partner

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