Intel Speedstep support?

[Elias Mårtenson]

(tested on a Dell Latitude E7470)

If I enable Intel Speedstep in the BIOS settings and boot the machine without power plugged in, the CPU is incredibly slow (as in: It takes minutes to start a VM). If I boot the computer with power plugged in, the machine is as fast as I expect it to be.

Disabling Speedstep makes this problem go away. I'm guessing this is caused by the Speedstep drivers are not loaded in dom0, preventing the system from increasing the CPU speed (which is set to the slowest possible when booting on battery).

There doesn't seem to be any packages that contain the Speedstep drivers. Is there a way to get this to work?

[Marek Marczykowski-Górecki]

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I'm not sure how "Intel Speedstep" works, but regardless of this, Xen
already do handle power management, including adjusting CPU frequency
and C-states.

There is also xenpm tool, you can use in dom0 to adjust Xen power
management settings.

- --
Best Regards,
Marek Marczykowski-Górecki
Invisible Things Lab
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
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