[PD] new raspberries

[Miller Puckette]

Also try running "pd -nosleep", which sometimes persuades kernels to
schedule the process differently :)

M

On Fri, Feb 06, 2015 at 11:30:03PM +0100, katja wrote:
> Claude, thanks for the hint. My /boot/config.txt shows no special
> settings, so I guess the CPU is at a fixed frequency. It says that
> '700 MHz is the default' (while model 2B should be at 900 MHz). Seems
> I downloaded the 'newest' Raspbian too early (the day after model 2B's
> release)... Will try again.
> 
> Katja
> 
> On Fri, Feb 6, 2015 at 10:50 PM, Claude Heiland-Allen
> <claude at mathr.co.uk> wrote:
> > I've not got any version of the rpi, but maybe it's scaling down the clock
> > frequency of unused cores, which then takes some time to spin up to full
> > speed when a task is moved by the kernel?
> >
> > I also had issues on amd64 desktop and core2duo laptop with pd -rt not being
> > taken into account by the kernel ondemand cpu speed governor, or some other
> > issue perhaps, whereby the cpu speed would stay at ~800MHz even though it
> > really needed to be higher to reduce xruns etc..  pd -nrt would scale up the
> > cpu speed correctly.
> >
> >
> > On my quad-core amd64 desktop I run this before realtime work (or nrt
> > benchmarking) to set all cores to maximum speed (with the 'performance'
> > governor):
> >
> > for c in 0 1 2 3 ; do sudo cpufreq-set -c $c -g performance ; done
> >
> > Then when I want to reduce fan noise / heat etc and I'm not doing much
> > intensive, I reset to the default 'ondemand' governor:
> >
> > for c in 0 1 2 3 ; do sudo cpufreq-set -c $c -g ondemand ; done
> >
> >
> > Might also be worth looking into setting scheduler cpu core affinity for pd,
> > jackd, pd-gui, ...  but I don't know how to do that.
> >
> >
> > Claude
> >
> > On 06/02/15 21:38, katja wrote:
> >>
> >> Aplay can play a .wav file without trouble, so it is not a general
> >> problem with the audio hardware or drivers on Pi 2b.
> >>
> >> I installed command htop to see CPU load per core. It's interesting,
> >> the load switches from one core to another, and sometimes they all
> >> seem to be almost idle even with a heavy Pd patch running.
> >
> >
> > --
> > http://mathr.co.uk
> >
> >
> >
> > _______________________________________________
> > Pd-list at lists.iem.at mailing list
> > UNSUBSCRIBE and account-management ->
> > http://lists.puredata.info/listinfo/pd-list
> 
> _______________________________________________
> Pd-list at lists.iem.at mailing list
> UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list