On Fri, 27 Jun 2008 17:13:24 +0100
Richard Hughes <hughsient(a)gmail.com> wrote:
At the moment we set:
# CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE is not set
This is not ideal from a power-saving point of view.
In an ideal world we would:
* remove CONFIG_CPU_FREQ_GOV_CONSERVATIVE -- ondemand does a better
job on all workloads
* remove CONFIG_CPU_FREQ_GOV_USERSPACE -- we have nothing in
userspace that needs this sort of control, and if we did, the latency
would be horrible
* remove CONFIG_CPU_FREQ_GOV_POWERSAVE -- ondemand automatically
throttles down to lowest, and is just a hardcoded state
* compile into the kernel CONFIG_CPU_FREQ_GOV_ONDEMAND -- we really
want to be running this on all systems that support it
* set ONDEMAND or PERFORMANCE to default as USERSPACE is just
changed to something else by cpuspeed. You really don't want to be
using USERSPACE at all.
Matthew Garrett and I are working on a latency profile for power
management, and having all these modules potentially loaded is bad.
I totally agree with your suggestions.
If you want to reach me at my work email, use arjan(a)linux.intel.com
For development, discussion and tips for power savings,