Mark.Haywood wrote: > Li, Aubrey wrote: >> Rafael Vanoni Polanczyk wrote: >> >> >>> Aubrey Li wrote: >>> >>>> 2008/6/23 Rafael Vanoni <Rafael.Vanoni at sun.com>: >>>> >>>>> Forgot to zero cstate_info[i].events, here's the correct diff. >>>>> >>>>> >>>> Thanks for the great work, :-) >>>> This one looks good except this: >>>> >>>> -static char cpupm_treshold[] = " echo cpu-threshold 1s >> >>>> /etc/power.conf"; +static char cpupm_treshold[] = " echo >>>> cpu-threshold 5s >> /etc/power.conf"; >>>> >>>> why do we need this change? >>>> >>>> >>> Sorry I didn't comment this one before. 1s seems a bit too little, >>> don't you think? I can't remember the default, tho. >>> >>> thanks >>> rafael >>> >> >> Not really, intel processor can switch very quickly (in >> microseconds). That's why we are working on the subsecond p-state. >> So here, we should set this threshold as small as possible, 1s is >> the right value. >> > > I've not really been following this thread. But why is this > change being > proposed and is the proposal that the change be a productized > change to > Solaris? If so, please don't. I'm currently looking into making this > same change, enabling CPU power management by default and > modifying the > Solaris PM framework to scan CPU devices once a second: > > 6647538 cpupm should be on by default > 6714184 x86 CPU power management could be a little more aggressive. > > Just changing cpu-threshold to 1 second (as I think you are proposing > above) isn't going to have much effect without the changes I'm > planning with the CRs above. Also, I'm currently running these > changes through our PerfPIT to see if they will have any impact on > performance. > > Sorry, if I've misunderstood the intent and for not following this > thread more closely. >
PowerTOP will detect if cpupm is enabled in /etc/power.conf. If it does, then it will do nothing, otherwise it will insert "cpupm enable" "cpu-threshold 1s" into power.conf and run pmconfig. The original threshold is 1 second and Rafael want to change it to 5 seconds, I'm just suggesting not to do that. Thanks, -Aubrey
