I've done more testing and found that what I've been experiencing may or
may not be replicating this bug. I was loading the processor using
Prime95 (available at http://www.mersenne.org/freesoft.htm) to test each
core under load. The reasons the ondemand cpu frequency governor was not
ramping up the multiplier while running this software's torture test
(which should completely load the cores) had to do with the default
gconf cpu frequency power settings. I needed to change the settings to
inform gnome to consider niced processors in the processor load
calcuation. Under the default settings, the niced processes were not
considered as part of the load, and the cpu multiplier stayed at idle. I
was able to use gconf-edit to find this buried setting. Once niced
processes were included in the load calculation, the multiplier
increased appropriately.

I missed these settings before because I did not find them under either
System > Preferences > Power Management or in the preferences for the
cpu governing applet. I was able to find them by running gconf-edit,
then browsing to apps > gnome-power-manager > cpufreq I find there the
following important power management settings:

consider nice

"Whether or not niced processes should be considered on processor load
calculation"

performance_ac

"The cpufreq performance value used to scale the processor when on AC
power."

performance_battery

"The cpufreq performance value used to scale the processor when on
battery power."

policy_ac

The cpufreq policy used to scale the processor when on AC power.
Possible values are ondemand, conservative, powersave, userspace,
performance, nothing.

policy_battery

"The cpufreq policy used to scale the processor when on battery power.
Possible values are ondemand, conservative, powersave, userspace,
performance, nothing."

Two questions to consider. Should the consider_nice variable be checked
by default to help niced CPU intensive processes use all available
processing? Contributors to distributed computing projects, such as the
Mersenne Prime project, video transcoding software, etc, I think would
benefit from a more sensible default.

Even if the default options aren't changed, shouldn't these options
appear in the preferences for Power Management, the cpu frequency
scaling applet, or some other more easily accessible location? If I have
missed where these settings are otherwise located, please let me know.
But if I haven't, I think these settings should be easier to find,
especially for laptop users.

Finally, I do not know if the original user who submitted this bug was
mislead as I was, so the original problem may well be different. I'm
regressing the bag from confirmed back to new as a result.

-- 
ondemand governor does not use maximum frequency under load
https://bugs.launchpad.net/bugs/122993
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