11 May
2021
11 May
'21
5:26 p.m.
Hi Linux Audio Enthusiasts!
I'm a fairly long-time JACK user (more than a decade, anyway), but I
must admit I don't really know it that well. I'm seeking guidance with
the following situation.
I am hearing audio "drop-outs" (a second or two of silence) that seem to
coincide with this error in jackd output:
JackAudioAdapterInterface::PushAndPull ringbuffer failure... reset
The audio hardware is a Digigram LX-DANTE connected to the JACK graph
via ALSA device hw0,0. jackd --version is
jackdmp version 1.9.18 tmpdir /dev/shm protocol 8
Also, jackd output fairly regularly (several times per minute) shows
messages like:
JackRingBuffer::Write : consumer too slow, skip frames = 1024
and
JackLibSampleRateResampler::ReadResample error written_frames = 1020
Output available = 1022
Where the number after the "=" in the "written_frames" line is
between
1020 and 1023, and the number in "Output available" is always two
greater than the previous.
I start jackd (as Linux user 'root') with the command:
/usr/bin/jackd --realtime --name default -d dummy -r 48000
And then add the Digigram client with the command:
/usr/bin/jack_load -i "-d alsa -d hw:0,0 -i 64 -o 64 -r 48000 -p 1024 -n
2" Digigram audioadapter
Thanks for any thoughts about these drop-outs! And please let me know if
there are other troubleshooting tools available.
Best,
~David Klann
11 May
11 May
6:10 p.m.
On Tue, 11 May 2021 13:26:17 +0000 David Klann wrote:
Hi Linux Audio Enthusiasts!
Hi David,
[...]
I start jackd (as Linux user 'root') with the
command:
/usr/bin/jackd --realtime --name default -d dummy -r 48000
My hunch is that this could be the problem. I seem to remember
it being said here that it should not be started by user 'root'.
I'm sure someone more knowledgeable will correct me if I'm wrong,
but maybe try starting it as an unprivileged user. or explain why
you start it as root?
--
HTH, John.
6:51 p.m.
Greetings John,
Thanks for your speedy reply!
On 5/11/21 09:10, you wrote:
On Tue, 11 May 2021 13:26:17 +0000 David Klann wrote:
Arrgh. Unfortunately, I have no control over this one aspect of the
system. This is a Rivendell radio automation system
(https://rivendellaudio.org/) and the way in which Rivendell is
currently coded, jackd *must* run as root. I have dug into the Rivendell
C++ code to determine the reason for this, and I have learned that it is
a core part of Rivendell. Changing this would require a significant
refactoring of the code.
Hey, wait! I just re-read the jackd manual page and noticed the
paragraph about $JACK_PROMISCUOUS_SERVER. Does this mean I can run jackd
as a non-root user as long as the group permissions line up?
Also, since my original posting, I have been digging in deeper to the
values I am using for --period (1024), --nperiods (2), and --rate
(48000), and their relation to the latency setting on the Dante network.
The sample rate is governed by the Dante network, but I can change the
period size and the number of periods.
I intend on fiddling with these as soon as possible. This computer is
actually in production, keeping radio station WRFI, Ithaca, NY, US on
the air, so we have to plan ahead to make changes to Rivendell.
Thanks again John!
~David
Hi Linux Audio Enthusiasts!
Hi David,
[...]
I start jackd (as Linux user 'root') with
the command:
/usr/bin/jackd --realtime --name default -d dummy -r 48000
My hunch is that this could be the problem. I seem to remember
it being said here that it should not be started by user 'root'.
I'm sure someone more knowledgeable will correct me if I'm wrong,
but maybe try starting it as an unprivileged user. or explain why
you start it as root?
12 May
12 May
7:07 p.m.
Sorry, originally meant to send this to the list, I think I accidentally
sent directly to David the first time.
On Tue, May 11, 2021 8:26 am, David Klann wrote:
I start jackd (as Linux user 'root') with the
command:
Presumably that is because Rivendell services are running as root. I
understand you can't do anything about the Rivendell design, but that is
not the recommended approach, if you look at any modern linux system the
system services are not running as root as a security precaution,
especially any network facing services.
/usr/bin/jackd --realtime --name default -d dummy -r
48000
And then add the Digigram client with the command:
/usr/bin/jack_load -i "-d alsa -d hw:0,0 -i 64 -o 64 -r 48000 -p 1024 -n
2" Digigram audioadapter
Why are you running jackd with the dummy backend and accessing the
Digigram card with audioadapter? Why not run jackd with the ALSA backend
and access the card directly?
As an aside, I have not looked at the 1.9.18 update for jackd, is
audioadapter the internal client version of zita-a2j? I know jackd v1 had
that for a long time, but I believe 1.9.18 is the first jackd v2 version
which has that feature.
--
Chris Caudle
1087
days inactive
1088
days old
linux-audio-user@lists.linuxaudio.org
3 comments
3 participants
participants (3)
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Chris Caudle -
David Klann -
John Murphy