[LAD] Towards a truely realtime capable FOSS audio distribution | A guide to the Jack Source Code

Hello everybody, my name is micu and I study computer science at the Dresden University of Technology. During an internship at the operating systems chair of the university, I ported ALSA to the chairs operating system DROPS aka TUD:OS [1,2]. To let ALSA talk to the hardware and provide to it the usual linux kernel environment DDEKit / DDELinux [3] were used. As a kernel-userland interface I wrote a very small emulation layer, which makes it possible to link SALSA-lib [4] against the ALSA "kernel" part. So right now, we have a somewhat stable ALSA server running in userland on top of DROPS without changing ALSA or the SALSA-lib source code. I have been continuing this project within my diploma thesis. The remit of the thesis can be found here [5]. It is the goal of the thesis to take some steps towards a truly realtime capable (meaning with time constraints to be guaranteed) FOSS audio distribution. Here [6] you can see a raw version of my requirements definition. The architecture we are going to use is --- how could it be different :) --- Jack or Jackdmp (with a strong bias towards Jackdmp). To get the mess out of my head, I wrote a short guide [7] to the Jack source code. It is a pretty raw version and it isn't finished in any way yet; but I won't work on it any longer. Nevertheless, it might be helpful to other developers new to Jack. Therefore, if you will, you may get it under any license you wish (attribution of the author is appreciated :) to publish and improve it. Of course, the long term goal of the project won't be met to any extent during my thesis and I have no idea, if this project will be continued here at the university. Neither do I know, whether I will have time to work on it afterwards. To make a long story short: I would like to ask my first three questions.... so far :) 1.) Do you agree on having a truly real-time capable architecture in the FOSS audio world would be a really great thing --- and would you say, getting such a thing maybe could get a (major) goal of the pro audio FOSS community? 2.) Concerning our Jack vs. Jackdmp decision: http://jackaudio.org/ says, Jackdmp is going to be Jack 2.0. How likely and how soon do you think is this going to happen? 3.) I guess, there is a very minor bug in the lines 236, 237 of libjack/driver.c, svn revision 2734: The type castings should be switched. Thanks a lot in advance and please excuse my bad english :(. Regards, micu BTW: I love Jack and I love ardour --- and therefore I love you :). ========================================== [1]http://www.realtimelinuxfoundation.org/variants/variants.html#VARIANTS_DR… [2]http://www.osnews.com/story.php/15814/Introduction-to-TUD-OS/ [3]http://demo.tudos.org/dsweeper_tutorial.html [4]http://www.alsa-project.org/main/index.php/SALSA-Library [5]http://www1.inf.tu-dresden.de/~s3418892/task.txt [6]http://www1.inf.tu-dresden.de/~s3418892/Require.pdf [7]http://www1.inf.tu-dresden.de/~s3418892/AgttJSC.txt -- GnuPG: https://www1.inf.tu-dresden.de/~s3418892/micuintus.asc Fingerprint: 1A15 A480 1F8B 07F6 9D12 3426 CEFE 7455 E4CB 4E80