P4 throttling on Atom N270

twix · 2011-02-07 19:41:34

Hi,

I have an Toshiba NB100 netbook with N270 and when digging into the /proc/ directory, I found this :

/proc/acpi/processor/CPU{0,1}/throttling.

It show the current and available throttling state (in this case it's about skipping clock cycle in order to reduce virtually heat and power consumption.
But with recent processors with C-states and frequency change, this throttling is totally irrelevant.

I can change the throttling state by echoing into these files, but the "fan" button on the netbook "activate" throttling, and rebooting too.

So I looked into kernel config, but found nothing but P4 clockmode, which i have disabled but it keeping throttling.

In lsmod, apart acpi_cpufreq i have nothing like throttling

Do you have any idea ?

Thanks you

Last edited by twix (2011-02-07 19:46:16)

rwd · 2011-02-07 21:08:47

I think you need to clarify your question. What do you want to achieve, and/or why you conclude that something is 'keeping throttling'.

twix · 2011-02-08 07:42:37

Ok there it is :

cat /proc/acpi/processor/CPU0/throttling
state count: 8
active state: T1
state available: T0 to T7
states:
T0: 100%
*T1: 87%
T2: 75%
T3: 62%
T4: 50%
T5: 37%
T6: 25%
T7: 12%

So I got only 87% of my CPU power, wich is bad for powersaving (again, this technique is deprecated).

If i activate the fan of my computer (with kb hardware button), or if I echo 0 into it, it'll be unthrottled

cat /proc/acpi/processor/CPU0/throttling
state count: 8
active state: T0
state available: T0 to T7
states:
*T0: 100%
T1: 87%
T2: 75%
T3: 62%
T4: 50%
T5: 37%
T6: 25%
T7: 12%

But I want to completely disable it (preferably removing it in kernel), or if you have another work-around i will be pleased anyway !

Thanks

Arch Linux

#1 2011-02-07 19:41:34

P4 throttling on Atom N270

#2 2011-02-07 21:08:47

Re: P4 throttling on Atom N270

#3 2011-02-08 07:42:37

Re: P4 throttling on Atom N270

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