topic Itanium 2 DVFS in Software Archive

Itanium 2 DVFS

elesueur — Mon, 10 Dec 2007 00:50:11 GMT

Hi,

I am a student working on a project aimed at measuring the power savings obtained by using DVFS on the Itanium 2. I have an HP rx2600 which has dual 900MHz McKinley processors, and I have recompiled my kernel with the acpi-cpufreq driver built in. However, the interface for acting upon the driver is not available.

Do these cores actually support DVFS?

Does it need to be turned on in EFI?

Regards,
Etienne Le Sueur

Re: Itanium 2 DVFS

TimP — Mon, 10 Dec 2007 01:45:57 GMT

I haven't heard of IA-64 processors of 5 years ago supporting power saving idle techniques. In any case, there were relatively few reliable 900Mhz CPUs made. 1300Mhz was in production by the time the disabling errata were corrected. My own power saving and office comfort technique is to shut down the old IA-64 when I don't need it. I went through 3 of those machines before I got a reliable one.

Re: Itanium 2 DVFS

elesueur — Mon, 10 Dec 2007 01:58:23 GMT

Ok, thanks for that info...

Do you know of any of the Itanium models which are known to support DVFS?

I have access to an HP rx2660 which is based around the 1.42 GHz/12 MB Dual-core (9120N) or the 1.66 GHz/18 MB Dual-core (9140M) Itanium processors.

if anyone has actually used DVFS on any Itanium model and had it work, could they please let me know?

Many thanks

Re: Itanium 2 DVFS

Adam — Fri, 24 Oct 2008 12:18:14 GMT

Quoting - elesueur

At least Montecito or newer support power management techniques.

Montecito was released in 2006.