Problem on AMD64

[Alexander Motin]

Dmitry Kolosov wrote:
> Could you give to us some links about powersaving with EST? For now, i'm using 
> powerd: 
> powerd_enable="YES" 
> powerd_flags="-a maximum -b adaptive -n adaptive -r 30 -i 35" 
> in my rc.conf. I'm not on AMD64, so i'm sorry, powerd works well to me (125 MHz 
> on battery and 2.16GHz on AC), BUT battery life time is equal in both cases and 
> something about 50 minutes, so i think powerd is not so powerfull for me.

powerd uses any frequency control features provided by kernel. On P4 and 
above kernel may provide both EST and P4TCC frequencies. You can see 
them by `sysctl -a | grep freq`.
P4TCC usually gives very small power benefit on idle CPU. I have seen 
benefit only on old P4 without or later with disabled C1E mode support. 
For CPUs with C1E support P4TCC is not effective as CPU anyway 
completely disables it's frequency on C1 state (HALT instruction).
EST instead is much more effective as it also controls CPU voltage. 
Check your boot messages and sysctls for EST support.

-- 
Alexander Motin