SpeedStep on Pentium M

Gabri.91

Hi, I have made a Mini-ITX firewall with PFsense. How can I enable Pentium-M speedstep and see the CPU actual speed on the home widget?
Thanks

ryates

Do you have PowerD enabled under "System: Advanced: Miscellaneous tab"? Beyond that it should work.

Be aware that the Dashboard does not poll often enough to give a fine-grained picture of cpu scaling but will show if it is heavily loaded.

stephenw10

You may also have to switch your kernel timecounter to something other than TSC. Check the system logs for many error messages!
The earlier, 400MHz FSB, Pentium-Ms are better supported.

Steve

Gabri.91

I've enabled PowerD, but when I stress the firewall it crashes and also in physical console becomes unresponsive..

You may also have to switch your kernel timecounter to something other than TSC

Could be this the problem? How can I verify or change?
Unfortunately is a 533Mhz version (Pentium-M 740).

Do you think that power consumption changes considerably activating SpeedStep?

PS: Anyway I'm very satisfied of the performance (about 100-120Mb\s VPN throughput and 600-650Mb\s routing throughput)

stephenw10

Usually if you have an incompatible timecounter set then the logs get filled with errors very quickly. Something like:

kernel: timecounter TSC must not be in use when changing frequencies; change denied

You can check from the command line:


[2.0.1-RELEASE][root@pfsense.fire.box]/root(3): sysctl kern.timecounter.hardware
kern.timecounter.hardware: TSC
[2.0.1-RELEASE][root@pfsense.fire.box]/root(4): sysctl kern.timecounter.choice
kern.timecounter.choice: TSC(800) i8254(0) dummy(-1000000)

I don't have speedstep on that machine so I haven't switched from TSC.
I think I noted most of what you need to do here:
http://forum.pfsense.org/index.php/topic,20095.msg161139.html#msg161139

My experience with 2GHz Pentium-M 760 was that the est(4) driver brought up an incorrect set of speedstep frequencies and the logs filled with 'calcru: runtime went backwards' errors. This may be solvable though.

On my box I saved 5W at idle, about 15%. I saved far more with a DC power supply.

Steve