[Jack-Devel] How does --hwmon work?

[David Kastrup]

Ralf Mardorf <ralf.mardorf at alice-dsl.net> writes:

> On Sat, 06 May 2017 22:24:29 +0200, David Kastrup wrote:
>>dak at lola:~$ ps ax k priority -o priority,comm |grep irq
>>-91 irq/8-rtc0
>>-81 irq/17-firewire
>>-71 irq/32-snd_hda_
>> [snip]
>> 20 irqbalance
>>
>>Looks like somebody is prioritizing my soundcards.
>
> Much likely it's Rui's rtirq script. For what ever reason Ubuntu
> keeps it in init.d and doesn't start it by a systemd unit.
>
> http://packages.ubuntu.com/yakkety/rtirq-init
>
> Instead of ps, you could run
>
> /etc/init.d/rtirq status
>
> I can't speak for your computer, but usually rtc shouldn't be
> prioritised anymore and irqbalance should be completely removed.

It's been years since I touched the config file.  Probably I should
remove, install from scratch.

Oh wait.  snd_hda_ would be the laptop internal sound card, not the
Hammerfall DSP.  The latter doesn't have its own interrupt apparently,
so this would rather be, uh, irq/16-yenta ?  That one's at the bottom in
the list.  Darn it.  I probably removed it when I put the Hammerfall
into storage.  And got it out again since the Mackie Onyx mixer is too
bulky for Free Software conference duty.

So maybe I should give the Hammerfall a better chance at working.

> Take a look at /etc/default/rtirq (on Arch Linux
> it's /etc/conf.d/rtirq ;):
>
> [rocketmouse at archlinux ~]$ grep RTIRQ_NAME_LIST /etc/conf.d/rtirq | grep -v "#"
> RTIRQ_NAME_LIST="usb snd_hdsp snd_ice1"

You probably have a PCI (or express) card rather than a Cardbus one?

> Check the output of
>
> cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
>
> Perhaps setting it to performance helps to reduce xruns

I seem to remember that CPU switching speed with the Penryn is supposed
to be close enough, but I admit that if it were instantaneous it would
be indistinguishable from a power-saving halt state but full speed
otherwise.  I think I had the system on performance for a while but it
did not make a noticeable difference with regard to xruns.

I'll keep it in mind.

-- 
David Kastrup