Description of problem: Pro Audio people require a mechanism to provide preferential scheduling to audio applications. RT limits patch has been merged upstream. More information available here http://www.steamballoon.com/wiki/Rlimits Expected results: Provide a mechanism for audio professionals to use this capability in a non intrusive secure way Additional info: Distributions like Agnula (http://www.agnula.org/) and repos like Planet CCRMA (http://ccrma.stanford.edu/planetccrma/software/) depend on similar functionality.
*** This bug has been marked as a duplicate of 157050 ***
I already did a release of 2.6.12-rc4 low latency kernels (they include the realtme preempt patches from Ingo Molnar) at Planet CCRMA and a suitably patched pam that enables access to realtime scheduling and memory locking "out of the box", see the announcement here: http://ccrma-mail.stanford.edu/pipermail/planetccrma/2005-May/009139.html Before switching to the rlimits patch I was relying on the realtime lsm kernel module by Jack O'Quin to get the same results. The source package for the modified pam is here: http://ccrma.stanford.edu/planetccrma/mirror/all/linux/SRPMS/pam-0.77-66.2.3.src.rpm and the kernel is here: http://ccrma.stanford.edu/planetccrma/mirror/all/linux/SRPMS/kernel-2.6.11-0.10.rdt.src.rpm The patches to pam not only make it aware of the new limits options (that was part of the packages released in the steambaloon.com wiki referenced above) but also adds a bit of documentation to /etc/security/limits.conf and enables access to everyone by default (which is probably not what Fedora would do, in my case I need to install the whole thing and be ready to start apps that use realtime scheduling with no user configuration of /etc files - the Jack Audio Connection Kit audio server is the best example, many applications depend on it and it has to have access to realtime scheduling and memory locking to be of any use). BTW, the Fedora project should consider adding an "audio" group to the stock install, that would make configuration and restriction of permissions much easier.