[linux-audio-dev] Other real-time options

Hi, After the debate regarding inclusion of realtime-lsm in the main tree, it seems like other approaches to unprivileged real-time have shown up. Both Con Kolivas and Ingo Molnar have come up with different (cleaner to the kernel developers) solutions. Both are described at: http://lwn.net/Articles/120024/ It seems like these solution have not been very popular yet, although I think they still have better chances of eventually being merged. I haven't tried Ingo's patch yet, but I can say that Con's SCHED_ISO_{FIFO,RR} (http://ck.kolivas.org/patches/SCHED_ISO/2.6.11.6-iso3.1.diff) works pretty good. Also, one nice feature that both approaches have is that you can set a limit on the amount of CPU a user RT task can use, preventing a user to lock up the machine. The way I see it, there are three important parts to a good solution: 1) Make sure no user can lockup the system with a "while(1);", so IMO realtime-lsm isn't the best solution (though I'm not strongly against) 2) Have per-user control, so that you can automatically restrict real-time tasks to only the person physically logged in. This would be important for a desktop configuration and would mean a distribution could enable this be default. 3) Making sure user tasks are lower priority that privileged tasks. Right now, Con's patch does 1 and 3, while Ingo's does 1 and 2 (though Con says Ingo's patch could also do 3). Would people here be happy with any of those and try to convince kernel developers that there's really a need for real-time (some still aren't convinced) and that one of these solution is acceptable? Jean-Marc -- Jean-Marc Valin <Jean-Marc.Valin(a)USherbrooke.ca> Université de Sherbrooke