[PlanetCCRMA] SSE2 detected - cannot lock down memory for RT thread

Fernando Lopez-Lezcano nando@ccrma.Stanford.EDU
Fri May 19 12:58:00 2006


On Fri, 2006-05-19 at 12:09 -0700, Ben Gillespie wrote:
> Hi, everyone,
> I recently installed FC5 and when I run Qjackctl I get this message;
>  
>  
> SSE2 detected
> cannot lock down memory for RT thread (Cannot allocate memory)
> cannot use real-time scheduling (FIFO at priority 61) [for thread
> -1211692128, from thread -1211692128] (1: Operation not permitted) 
>  
> JACK: unable to mlock() port buffers: Cannot allocate memory
> cannot use real-time scheduling (FIFO at priority 72) [for thread
> -1230771296, from thread -1230771296] (1: Operation not permitted)
> cannot use real-time scheduling (FIFO at priority 62) [for thread
> -1241261152, from thread -1241261152] (1: Operation not permitted)
>  
>  
> WHA'S UP!
>  
> Planet-edge kernel
>  
> kernel-2.6.16-1.2080.13.rrt

How did you install the Planet CCRMA core components? 

If you just installed the kernel alone you are missing parts. You should
install with "yum install planetccrma-core-*" (with "*" depending on
what you want). This is explained (for now) here - and related threads:

http://ccrma-mail.stanford.edu/pipermail/planetccrmanews/2006-May/000034.html

For the above to work you need to either install the pam that is part of
planetcore, or manually configure /etc/security/limits.conf to allow
normal users to both lock down memory and have access to realtime
scheduling. Something like this should be in that file:

----
# or (default) allow everyone access
*               -       rtprio          99
*               -       nice            -10
*               -       memlock         4000000
----

If you did not install the planetccrma-core meta package you are
probably also missing the rtirq package, which will reorder the
interrupts (for kernels patched with Ingo's realtime preemption patch)
so that audio has more priority than other stuff. 

-- Fernando