Intel Turbo Boost not working

[e100]

I have an Intel E5-2650.

Turbo Boost never seems to kick in.
I used this to validate if it was enabled and working: http://code.google.com/p/i7z/
It does report that it is enabled, but it never kicks in.

There is a patch to fix this that shipped in 2.6.33-rc5 https://bugzilla.kernel.org/show_bug.cgi?id=15064#c26

Would it be possible to get this patch included in the Proxmox kernel?

 

[e100]

I made some progress.
I added "intel_idle.max_cstate=0 processor.max_cstate=1" to the kernel command line

Then enabled the modules:
freq_table
acpi_cpufreq

I changed /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor to performance, I suspect there is some global setting somewhere just not found it yet.

Now all 8 cores run at 2.4Ghz instead of just 2.0Ghz

Not sure which changes made the most difference or if all are needed but I will test more and post back once I know.

 

[mir]

I made some progress.
I added "intel_idle.max_cstate=0 processor.max_cstate=1" to the kernel command line

Then enabled the modules:
freq_table
acpi_cpufreq

I changed /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor to performance, I suspect there is some global setting somewhere just not found it yet.

Now all 8 cores run at 2.4Ghz instead of just 2.0Ghz

Not sure which changes made the most difference or if all are needed but I will test more and post back once I know.

AFAIK the scaling_governor only controls how stepping of the CPU is performed.

 

[dietmar]

There is a patch to fix this that shipped in 2.6.33-rc5 https://bugzilla.kernel.org/show_bug.cgi?id=15064#c26

What patch exactly? https://bugzilla.kernel.org/attachment.cgi?id=24658 is already included.

 

[e100]

Knowing that patch is included is helpful.
I have not been able to get Turbo Boost to work perfectly but I have managed to get it to kick on for every core all the time.
My nehalem cpus seem to work better, they will change clock up or down from the base clock depending on the load.
The sandy bridge I have will by default scale down from the base clock, but have no turbo boost, with some tweaks I can get it to always run in turbo boost mode but never scale down.

To get the most performance with virtually no power saving from the nehalem or sandy bridge I did the following:
edit /etc/default/grub and add "intel_idle.max_cstate=0 processor.max_cstate=1" to GRUB_CMDLINE_LINUX

# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.

GRUB_DEFAULT=0
GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet"
GRUB_CMDLINE_LINUX="[B]intel_idle.max_cstate=0 processor.max_cstate=1[/B]"

run update-grub

install cpufrequtils:
aptitude install cpufrequtils

Create the file /etc/default/cpufrequtils with these contents:

GOVERNOR="performance"

Then reboot so all of the changes can take effect.