13 Jul
2005
13 Jul
'05
6:12 p.m.
On Wed, 2005-07-13 at 08:09, Eric Dantan Rzewnicki wrote:
On Tue, Jul 12, 2005 at 01:46:13PM -0700, Fernando
Lopez-Lezcano wrote:
The latest "edge" kernels on Planet CCRMA (for fc3/fc4) use rlimits and
the repository includes a matching patched pam...
-- Fernando
On Tue, 2005-07-12 at 12:56, Iain Duncan wrote:
It makes (should make?) a
difference independent of whether you run as
root or not. If you run as root you can access everything. If you don't
run as root (highly recommended :-) you need some additional stuff to
get the same performance.
I vaguely recall that demudi stuck with the realtime-lsm for the current
version. Is this correct?
Are there deb packages of the patched pam available?
what about rpm's for ccrma?
>I've just joined the list and it's pretty interesting.
>Can someone tell me something about the differences between the
>preempt patch from Ingo and the "Realtime Linux Security Module"?
>I currently use the latter one and I'm quite satisfied as jack works
>really fast. Perhaps one should try this way instead of the vanilla
>kernel patch. There have to be pros and cons I'm interested in. Can
>someone point them out?
The LSM and Ingo's patches are addressing 2 separate issues. Ingo's
patch is working to minimize sources of latency in various code paths in
the kernel. The rtlimits and the realtime-lsm are addressing the issue
of providing a security model for realtime applications to get the
capabilities they need to run in real-time. Ordinarilly these
capabilities (CAP_SET_PCAP, mlockall(), and SCHED_FIFO()) are only
accessible as root. rtlimits and the realtime-lsm provide infrastructure
for allowing these capabilities to be granted to only a specified set of
users/processes.
So am I correct in believing that the preempt patch is the one
that
makes a difference if I intend to run as root anyway? ( Yeah I know I'm
not supposed to, but IMO my machine is just a synthesizer in disguise as
a computer and I'll unplug the ethernet cable if I need to. )
2.6.12 already
includes the rlimits patch that will allow you to run
well as a non-root user. But you will need a patch to pam (if your
distro uses pam) or a special user program to access realtime scheduling
as a non-root user (was posted not long ago to this list).