[linux-audio-user] The trouble with disks

[John Anderson]

On Fri, 2003-12-19 at 20:47, Mark Knecht wrote:
> An idea? Have you tried running an 'all software' experiment, or 'almost all
> software', to understand whether it's really the disk causing this? What
> happens if you load up a CD with Alsaplayer and play it, and then patch in
> some Jack clients like freqtreak, tapiir, etc., multiple times to create a
> lot of Jack traffic, but little or no hard disk traffic? You can create an
> arbitrarily complicated setup to maybe explore whether the problem is with
> Jack, or possibly with your motherboard, it's memory usage, other
> applications that are running. If these work right, but then a disk based
> operation fails, you have more info....

OK, running jackd -n 3 -p 256, a (pre-played ;-) ardour session,
alsaplayer with a CD, freqtweak reading from ardour and alsaplayer and
sending output to the card (two completely different audio streams.
Yuck.), with jack_lsp -c giving

alsa_pcm:capture_1
   ardour:bass/in 1
   ardour:mekody/in 1
alsa_pcm:capture_2
   ardour:bass/in 1
   ardour:mekody/in 1
alsa_pcm:capture_3
   ardour:Riddimpick/in 1
   ardour:Chords/in 1
   ardour:Vocal/in 1
   ardour:Mouette/in 1
   ardour:Chords2/in 1
alsa_pcm:capture_4
   ardour:Riddimpick/in 1
   ardour:Vocal/in 1
   ardour:Mouette/in 1
   ardour:Chords2/in 2
alsa_pcm:capture_5
alsa_pcm:capture_6
alsa_pcm:capture_7
alsa_pcm:capture_8
alsa_pcm:capture_9
alsa_pcm:capture_10
alsa_pcm:capture_11
alsa_pcm:capture_12
alsa_pcm:playback_1
   alsaplayer-6399:out_1
   ardour:Mix/out 1
   ardour:auditioner/out 1
alsa_pcm:playback_2
   alsaplayer-6399:out_2
   ardour:Mix/out 2
   ardour:auditioner/out 2
alsa_pcm:playback_3
   freqtweak_1:out_1
   ardour:Mix/out 1
alsa_pcm:playback_4
   freqtweak_1:out_2
   ardour:Mix/out 2
alsa_pcm:playback_5
alsa_pcm:playback_6
alsa_pcm:playback_7
alsa_pcm:playback_8
alsa_pcm:playback_9
alsa_pcm:playback_10
ardour:auditioner/out 1
   alsa_pcm:playback_1
ardour:auditioner/out 2
   alsa_pcm:playback_2
ardour:click/out 1
   ardour:stick/in 1
   ardour:Mix/in 2
   ardour:Mix/in 1
ardour:Violin/out 1
   ardour:Mix/in 1
ardour:Violin/out 2
   ardour:Mix/in 2
ardour:Viola/out 1
   ardour:Mix/in 1
ardour:Viola/out 2
   ardour:Mix/in 2
ardour:Chords2/out 1
   ardour:Mix/in 1
ardour:Chords2/out 2
   ardour:Mix/in 2
ardour:Mouette/out 1
   ardour:Mix/in 1
ardour:Mouette/out 2
   ardour:Mix/in 2
ardour:Vocal/out 1
   ardour:Mix/in 1
ardour:Vocal/out 2
   ardour:Mix/in 2
ardour:Chords/out 1
   ardour:Mix/in 2
   ardour:Mix/in 1
ardour:Riddimpick/out 1
   ardour:Mix/in 1
ardour:Riddimpick/out 2
   ardour:Mix/in 2
ardour:Durms/out 1
   ardour:Mix/in 1
ardour:Durms/out 2
   ardour:Mix/in 2
ardour:Mix/in 1
   ardour:bass/out 1
   ardour:mekody/out 1
   ardour:stick/out 1
   ardour:Chords2/out 1
   ardour:Mouette/out 1
   ardour:Durms/out 1
   ardour:click/out 1
   ardour:Riddimpick/out 1
   ardour:Chords/out 1
   ardour:Vocal/out 1
   ardour:Violin/out 1
   ardour:Viola/out 1
ardour:Mix/in 2
   ardour:bass/out 1
   ardour:mekody/out 2
   ardour:stick/out 1
   ardour:Chords2/out 2
   ardour:Mouette/out 2
   ardour:Durms/out 2
   ardour:click/out 1
   ardour:Chords/out 1
   ardour:Riddimpick/out 2
   ardour:Violin/out 2
   ardour:Vocal/out 2
   ardour:Viola/out 2
ardour:Mix/out 1
   freqtweak_1:in_1
   alsa_pcm:playback_3
   alsa_pcm:playback_1
ardour:Mix/out 2
   freqtweak_1:in_2
   alsa_pcm:playback_4
   alsa_pcm:playback_2
ardour:stick/out 1
   ardour:Mix/in 1
   ardour:Mix/in 2
ardour:mekody/out 1
   ardour:Mix/in 1
ardour:mekody/out 2
   ardour:Mix/in 2
ardour:bass/out 1
   ardour:Mix/in 1
   ardour:Mix/in 2
ardour:Viola/in 1
ardour:Chords2/in 1
   alsa_pcm:capture_3
ardour:Chords2/in 2
   alsa_pcm:capture_4
ardour:Mouette/in 1
   alsa_pcm:capture_4
   alsa_pcm:capture_3
ardour:Violin/in 1
ardour:Vocal/in 1
   alsa_pcm:capture_3
   alsa_pcm:capture_4
ardour:Chords/in 1
   alsa_pcm:capture_3
ardour:Riddimpick/in 1
   alsa_pcm:capture_3
   alsa_pcm:capture_4
ardour:Durms/in 1
ardour:Durms/in 2
ardour:stick/in 1
   ardour:click/out 1
ardour:mekody/in 1
   alsa_pcm:capture_2
   alsa_pcm:capture_1
ardour:bass/in 1
   alsa_pcm:capture_2
   alsa_pcm:capture_1
freqtweak_1:in_1
   alsaplayer-6399:out_1
   ardour:Mix/out 1
freqtweak_1:out_1
   alsa_pcm:playback_3
freqtweak_1:in_2
   alsaplayer-6399:out_1
   ardour:Mix/out 2
freqtweak_1:out_2
   alsa_pcm:playback_4
alsaplayer-6399:out_1
   freqtweak_1:in_1
   freqtweak_1:in_2
   alsa_pcm:playback_1
alsaplayer-6399:out_2
   alsa_pcm:playback_2

<Phew> You think that's arbitrarily complicated enough?

and jackd -v output like this

load = 18.0664 max usecs: 960.000, spare = 4373.000
load = 18.4838 max usecs: 1008.000, spare = 4325.000
load = 17.9706 max usecs: 931.000, spare = 4402.000
load = 18.1827 max usecs: 981.000, spare = 4352.000
load = 17.6607 max usecs: 914.000, spare = 4419.000
load = 18.2059 max usecs: 1000.000, spare = 4333.000
load = 18.2535 max usecs: 976.000, spare = 4357.000
load = 18.1086 max usecs: 958.000, spare = 4375.000
load = 17.9798 max usecs: 952.000, spare = 4381.000
load = 18.2811 max usecs: 991.000, spare = 4342.000
load = 18.1036 max usecs: 956.000, spare = 4377.000

and the processor at 100% because qjackconnect went to lala land (seems
to disagree with 2.6 kernels, qjackctl as well), there was 1 xrun in 2
minutes 40 seconds. I'm pretty sure I heard the disk do something around
about then...

So to confirm it, I said find /, and the xruns were popping up 1 every 3
or 4 seconds, and sometimes more often.

This was on vanilla 2.6.0 with Pre-emptible Kernel turned on, for those
who've been asking.

bye
John