Re: acpicpu slowing down computer [was Re: firefox slowness -- X server problem?]

[Jens Rehsack <rehsack%googlemail.com@localhost>]

2010/8/19 Jukka Ruohonen <jruohonen%iki.fi@localhost>:
> On Thu, Aug 19, 2010 at 02:38:43PM +0200, Thomas Klausner wrote:
>> Going back to a kernel from 20100702, firefox was fast again.
>> I looked at the dmesg differences and found that I had enabled acpicpu
>> in the meantime. I rebuilt a kernel using sources from yesterday, but
>> disabling acpicpu, and firefox is still fast; with a kernel from
>> yesterday and acpicpu enabled, it is slow.
>
> I think we need a little more information than a gut feeling.

But what kind of information we can provide? We're fishing in murky waters,
because we do know nothing else except our firefox/x11-apps reacting sloppy.

>> During boot, I always get:
>> aibs0: warning over limit on 'MB Temperature'
>> aibs0: warning under limit on 'CHASSIS1 FAN Speed'
>> aibs0: warning under limit on 'CHASSIS2 FAN Speed'
>> aibs0: warning under limit on 'CHASSIS3 FAN Speed'
>> aibs0: warning under limit on 'POWER FAN Speed'
>
> This has nothing to do with acpicpu(4).

But how do you explain the test result? My firefox is really
slow - it takes several seconds switching between windows.
And if I understood Thomas correctly, on his system it's the
same. After removing acpicpu(4) it's quick as it was before.
Side effect?

>> The CPU is
>> cpu0: "Intel(R) Xeon(R) CPU           W3520  @ 2.67GHz"
>> but it's often misregnized by NetBSD with a higher clockrate:
>> cpu0: Intel Core i7 (Nehalem) (686-class), 3207.40 MHz, id 0x106a5
>> (both lines from the same cpuctl output).
>
> Neither does this.
>
> The only way acpicpu(4) can currently slow down your computer in a
> deterministic manner is if you have something like estd(1) running and the
> available frequencies change dynamically, in which case something should
> appear in dmesg (if you boot with -x). (A sysctl knob-will be likely
> provided for this later, but this is still work in progress; there will be a
> request for testing later.)

Great \o/

/Jens