Re: intel_ips produces constant load of 1
From: Jesse Barnes
Date: Tue Mar 22 2011 - 11:50:20 EST
On Tue, 22 Mar 2011 08:00:39 +0100
Andreas Hartmann <andihartmann@xxxxxxxxxx> wrote:
> Jesse Barnes wrote:
> > On Sat, 19 Mar 2011 16:38:38 +0100
> > Andreas Hartmann <andihartmann@xxxxxxxxxxxxxxx> wrote:
> >> Hello,
> >> on my MSI CR620 laptop, intel_ips produces a constant load of 1, even if
> >> the machine is idle.
> >> The ips-monitor hangs in D state:
> >> ps aux | grep ips
> >> root 593 0.0 0.0 0 0 ? S 17:20 0:00
> >> [ips-adjust]
> >> root 594 0.0 0.0 0 0 ? D 17:20 0:00
> >> [ips-monitor]
> >> If the module isn't loaded, the load of the machine in idle mode is 0 as
> >> expected.
> > This is a reporting problem, and probably due to the schedule() call
> > and associated task state in the ips-monitor thread. I thought setting
> > the task state to interruptible would prevent this, but it seems like
> > it's not enough for the deferrable on-stack timers?
> > At any rate, it's not actually causing increased CPU usage, so you can
> > safely ignore it until we have a fix.
> I've got one more question (I found
> Where is the difference to the functionality the bios provides? I can't
> see (and hear :-)) any difference between with intel_ips and without
> The fan always runs at a minimal speed, very quiet.
> The fan is getting loader, if the load is getting high (during
> compile-sessions e.g.). If the compile session is ready, the fan get's
> slower again.
> If I check the "cpu MHz" in /proc/cpuinfo with or without intel_ips, I
> can't see any difference. The value never exceeds the value given in the
> model name. The lowest values are equal, too.
> What is the added value compared to the bios functionality? How can I
> check it?
Loading the IPS driver will allow graphics turbo. This can improve gfx
performance quite a bit (up to 3x on some synthetic workloads). If
you're not really using gfx though, the driver won't really do anything
Jesse Barnes, Intel Open Source Technology Center
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