Ardour Jack realtime

I am running 13.1 on an AMD 4 core. I installed all the latest “jack” software.
Down loaded Ardour, installed it, the only warning masg I got was something like "that system is running variable CPU frequency.
When starting Ardour, specifying the output file and click ok the MSG comes up

[ERROR]: JACK:Cannot use real-time scheduling (RR/5)(1 Operation not permitted)
[ERROR]: JACK:jackclient::AquireSelfRealTime error

Any idea to overcome this ?


I wonder if this could be a memory allocation issue? See this short thread for a much earlier release, where the OP posting included your error message, and I also posted there my /etc/security/limits.conf additions which I have always needed for jack, up to and including openSUSE 13.1 (but not using Ardour). Note the solution found by the OP in post #5:


The variable cpu frequency warning is related to the cpu’s ‘on demand’ status, I expect; so, this warns you that you will get x-runs (drop outs) if you don’t change that status.
It is not the reason why JACK doesn’t start though.

Have you set up a limits.conf file as consused mentioned?
Are you the user in the ‘audio’ group?
Do you use PulseAudio?

Also, there are limits to response time on audio-devices so if you have set the latency too low (below 5ms on some) it may refuse to start. I don’t know if you use QJackCtl, if you don’t I would recommend playing around with it to test for settings which work for you.

Yes, the audio group is also specified as the domain of “@audio” for each limit line added to /etc/security/limits.conf, as shown in that thread link provided.

If PulseAudio is enabled, it can be disabled when jackd is started using qjackctl > Setup… > Settings tab, and entering “pasuspender – jackd” (not the quote marks) in the “Server Prefix” input field under “Parameters”.

That works for me on 13.1. However when jackd is terminated, I have to restart PulseAudio but that may be as a result of running Tumbleweed here. It wasn’t always the case.


I added the user to the “audio” user-group and edited “limits.conf” as recommended !

Many thanks guys … Ardour starts up without any error msg … great !

Just wonder what else I am going to run into;)


Probably into quite a variety of topics:), but you should be fine.

What do you plan to do with Ardour: recording, composing …?

What do you plan to do with Ardour: recording, composing …?

I wrote a song and would like to sound it a bit more professional by eg. adding a bass line via midi. Just plainly recording it, guitar and voice does not make it. I wrote some other lyrics and want to compose a melodies for it.


All right, good luck:good: