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powernowd removal



I had filed a bug requesting the removal of powernowd as an obsolete
package.  I have since realized that the package is orphaned and the
developers-reference says that means it should be discussed here.

The reason for the removal is that the package is obsolete.  It has been
over 3 years since its original author issued the final release, stating
that there would be no more.  The reason for this is that power
management has been taken over by the kernel.

An objection was raised that the powernowd script works with the
p4-clockmod driver as the only way to control the frequency on older
P4s.  It appears however, that this module is marked as depreciated and
slated to be removed from the kernel as it does not actually save any
power, and the ondemand kernel governor was intentionally made to not
work with it.

>From the kernel git logs:

commit e088e4c9cdb618675874becb91b2fd581ee707e6
Author: Matthew Garrett <mjg@redhat.com>
Date:   Tue Nov 25 13:29:47 2008 -0500

    [CPUFREQ] Disable sysfs ui for p4-clockmod.

    p4-clockmod has a long history of abuse.   It pretends to be a CPU
    frequency scaling driver, even though it doesn't actually change
    the CPU frequency, but instead just modulates the frequency with
    wait-states.
    The biggest misconception is that when running at the lower 'frequency'
    p4-clockmod is saving power.  This isn't the case, as workloads running
    slower take longer to complete, preventing the CPU from entering
deep C states.

    However p4-clockmod does have a purpose.  It can prevent overheating.
    Having it hooked up to the cpufreq interfaces is the wrong way to
achieve
    cooling however. It should instead be hooked up to ACPI.

    This diff introduces a means for a cpufreq driver to register with the
    cpufreq core, but not present a sysfs interface.

    Signed-off-by: Matthew Garrett <mjg@redhat.com>
    Signed-off-by: Dave Jones <davej@redhat.com>


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