Question about speedstep and powerd

[vicking]

Hi all,

I've just setup a new system based on a Intel Atom C3558.

When I was going trough the bios I saw that by default EIST (Enhanced Intel Speedstep) was disabled and the same for ASPM.

Now I was wondering if I should enable it and also enable PowerD in Opnsense after that? Or should I just leave both disabled? Enabling only powerd without EIST wouldnt do much I think?

[Stormscape]

I'd enable both (that is, EIST and ASPM) unless ASPM is known to cause issues on your specific system. As a comparison, I have both powerd and speedstep running on my box, which is an Optiplex 3060.

[BrandyWine]

FW/router? Turn off all the power saving stuff (aspm). Speedstep is ok. I tune C states so that he cpu's don't go too low on freq. I running N150 device.

If you save $1(us)/yr in power, do you need to worry about $1, or possibly the device going full sleep un-expectantly?

[vicking]

But enabling speedstep would also require enable powerd in Opnsense right?

I did some testing but with or without speedstep, device idles always @ 19w. So don't think it makes much of a difference and I am better of disabling it

[BrandyWine]

I have powerd and aspm 100% disabled, I changed tunables for the C states so that the 4 cpu's can't go too idle, I think they rest around 1GHz, then when needed it can burts up to max. My bios does not have an option for "speedstep".

Under default config, with all the power stuff disabled, the cpu's would idle around 800MHz. I have writeup on all this in my "N150" thread, posted up several months ago. It's a good read.