Talk:HOWTO Jack
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You point out that alsa-lib needs to be compiled with the jack USE flag. What if it's compiled by the kernel? Since the 2.6 kernel includes alsa, someone should note if we need to unset these kernel options and compile alsa manually.--Herda05 06:11, 2 March 2006 (GMT)
R: It doesn't matter, alsalib and alsa drivers are not the same package. Jack will work just fine with the kernel's alsa modules or with the alsa-drivers package. --Dominique 71 11:10, 18 March 2006 (GMT)
I don't seem to have this file at all (I do, however, have a file called "/etc/asound.state" is that the same thing?) is it installed by any of the ALSA ebuilds, or should I just create it? Which program/binary reads the settings in this file? How does it differ from the previously mentioned "asound.state" (which look pretty similar in content). /zrajm
R: /etc/asound.conf is now /etc/conf.d/alsasound. It contain system wide setting for alsasound. /etc/asound.state (or /var/lib/alsa/asound.state with recent gentoo versions) is created at run time by alsa. It contain alsa drivers settings. It is not recommended to modify it, but in some cases (more info needed here), it can help to stop alsa with '/etc/alsasound stop', delete this file, and restart alsa with '/etc/init.d/alsasound start'.
The article is really helpful but I can't get mplayer started properly with jackd. When I start (X envoriment, without gui) it an empty window appears and then after a time sound starts but the window is still empty, no even a picture.
Could you tell me what the problem might be? R: I believe at the forum is a better place to ask for help.--Dominique 71 11:10, 18 March 2006 (GMT)
The article mentions the procedure for manually starting Jack, but how do you make it run automatically? Is there an init.d script?
R: As it's a QT based program it will start automaticly for KDE users. You can always use things like .xinitrc or .xprofile with other desktop environments.
Yes, I'm doing something like (taken from the man page):
jackd -Rv -d alsa -p 128 -n 3 -r 44100
I don't use init.d script.
[edit] There should be a section on how to configure realtime for audio group programs in the 2.6.12+ kernel series(where the realtime patch is inside the kernel) -vininim
It is not realtime inside 2.6.12+ kernels but preemption. To get full premption support, you need a Vanilla kernel with Ingo Molnar's patch. They are called rt-sources in gentoo. See pro audio production applications portage overlay --Dominique 71 11:10, 18 March 2006 (GMT) You must understand at preemption is about task shifting and the realtime-lsm or pam-Rlimits are about tasks priorities.
In a server, you want a lot of throughput (it implies less preemption). For a desktop, you want a responsive desktop (it implies more preemption at the price of less throughput). For an audio workstation, you want realtime audio operations, it implies not only more preemption but the ability to fix the task priorities. The realtime-lsm module or pam-Rlimits are only 2 ways to do the same thing, to fix the priorities of both the hardware and the software.
With a rt-kernel, the desktop responsiveness will depend of the processor load and of what you are doing with the box. If you are in the audio group, the desktop will be responsive at low processor load, but as the hardware also fix the priorities, more the processor load will become higher, less the desktop will be responsive, and that especially when doing audio work. But at the same time you will still get realtime operations from the sound system and no xrun in jack.--Dominique 71 18:37, 27 January 2007 (UTC)
[edit] fusd commpilling errors
you have got strange errors while tryig to compile fusd? check out this page http://arnout.engelen.eu/index.php/Installing_oss2jack
[edit] What package provides rtprio?
Entered a stub into the article asking to provide further info about a command used but NOT installed during a normal Gentoo install. (I did a pretty good search on Google and could not easily find which package provides rtprio except it's relevant man page. I'm sure if I searched another hour or two and/or asked via email/irc, would have found it.) Also included a previously existing comment into the stub. Remove when fixed. ;-) --Roger 18:25, 3 March 2008 (UTC)
