Re: [LAU] System Configuration: kernel, CPU frequency, hardware timers

On Tue, 28 Aug 2018, Ralf Mardorf wrote:

> Regarding Ubuntu (at least for Xenial) there indeed is 'ondemand' in
> /etc/rc.d/, /etc/init.d/. However, I stay with 'powersave' or 'ondemand'

Not any more. It is there until 16.04 at least but vanishes at least by
18.04 to be replaced by /lib/systemd/system/ondemand.service which calls
/lib/systemd/set-cpufreq. The name ondemand is, as you say, misleading
and powersave even more so. where powersave used to be "run at lowest
speed" it is now what ondemand was supposed to be, but handled by the cpu
itself. ondemand, I have read, uses more power than performance, but
powersave works correctly. my cpu temp is higher at idle in performance
than powersave... I don't have anything old enough to test ondemand with.
In anycase, ondemand.service sets powersave in my case.

Installing cpufrequtils and setting it to set performance at boot no
longer works as I said due to kernel modules missing at the time it runs
at boot.

Using a utility to change cpu govering on the fly according to use does
make sense.

For many people using usb devices at 128/2 or higher, this probably
doesn't matter, but I like to make things work as well as possible at 16/2
so that at higher latency I don;t get surprised... but most usb devices
don't work that low. (USB clock is 1ms so probably 32/2 is lowest).

USB is not a gift for low latency audio, but a great boon for Linix
compatablility.

--
Len Ovens
www.ovenwerks.net
_______________________________________________
Linux-audio-user mailing list
Linux-audio-user@lists.linuxaudio.org
https://lists.linuxaudio.org/listinfo/linux-audio-user