[tesla-dev] last five bugs listed on the page

[Li, Aubrey]

Mark.Haywood at Sun.COM wrote:

> Li, Aubrey wrote:
>> 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.
>> 
> 
> OK. I get to show my ignorance (again!). Why would PowerTOP modify the
> system's configuration? Is this done at the request of the user?
> 
Yes, PowerTOP will find if cpu is power managable, if so it gives a
suggestion to
the user to enable cpupm, and if the user wants,  it will help to do it
by just press
one key.

I recommend you to have a try, :-)

Thanks,
-Aubrey