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Subject: Re: Power consumption HZ100, HZ250, HZ1000: new numbers
From: Lee Revell <rlrevell@joe-job.com>
To: Tomasz Torcz <zdzichu@irc.pl>
Cc: linux-kernel@vger.kernel.org
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Date: Tue, 02 Aug 2005 10:58:21 -0400
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On Tue, 2005-08-02 at 11:13 +0200, Tomasz Torcz wrote:
> On Mon, Aug 01, 2005 at 08:19:42AM +0200, Stefan Seyfried wrote:
> > Lee Revell wrote:
> > > On Mon, 2005-08-01 at 00:47 +0200, Pavel Machek wrote:
> > >> I'm pretty sure at least one distro will go with HZ<300 real soon now
> > >> ;-).
> > >> 
> > > 
> > > Any idea what their official recommendation for people running apps that
> > > require the 1ms sleep resolution is?  Something along the lines of "Get
> > > bent"?
> > 
> > MPlayer is using /dev/rtc and was running smooth for me since the good
> > old 2.4 days.
> 
>  VMware also uses /dev/rtc. So is NTP, which is needed when time drifts.
> But they can't use /dev/rtc simultanously, as it's single-open device.
> So running ntpd denies vmware and mplayer access to RTC. Bummer.
> 

You could work around this to some extent by using the ALSA timer API
with the RTC timer.  I think this allows multiple open by setting the
RTC to tick based on the lowest common denominator.  It won't help
vmware and NTP though.

Lee