[PlanetCCRMA] JACK isn't getting realtime

[Fernando Lopez-Lezcano]

On Sat, 2005-02-12 at 21:14, Jon B wrote:
> (I got my Echo Indigo IO card today, and it seems to work nicely.)
> 
> But I just noticed that JACK isn't getting realtime capabilities:

Which distro? (I'll assume fc3 from your previous posts)
Which kernel? ("uname -r" to find out)

> 00:12:49.149 JACK is starting...
> 00:12:49.150 /usr/bin/jackstart -R -dalsa -dhw:2 -r48000 -p512 -n2
> 00:12:49.155 JACK was started with PID=6280 (0x1888).
> jackstart: cannot get realtime capabilities, current capabilities are:
>            =ep cap_setpcap-ep
>     probably running under a kernel with capabilities disabled,
>     a suitable kernel would have printed something like "=eip"
> back from read, ret = 1 errno == Success
> jackstart: could not give capabilities: Operation not permitted
> jackd 0.99.36
> 
> I thought this was built in to the kernel by default?  Where do I look first?

If the kernel is one of the rdt series (latest is 2.6.10-0.5.rdt) and if
you installed the kernel through the planetccrma-core-* meta packages
then you should have the rtload script active that loads the realtime
kernel module. See if the module is loaded:

  /etc/rc.d/init.d/rtload status

If you are using the "normal" 2.6.10 kernel you also have to have the
realtime module loaded. 

> Also I get these:
> 
> delay of 24737.000 usecs exceeds estimated spare time of 10581.000; restart ...
> delay of 24803.000 usecs exceeds estimated spare time of 10581.000; restart ...
> delay of 24838.000 usecs exceeds estimated spare time of 10581.000; restart ...
> delay of 24794.000 usecs exceeds estimated spare time of 10581.000; restart ...
> delay of 24857.000 usecs exceeds estimated spare time of 10581.000; restart ...
> delay of 24743.000 usecs exceeds estimated spare time of 10581.000; restart ...
> delay of 24852.000 usecs exceeds estimated spare time of 10581.000; restart ...
> delay of 24699.000 usecs exceeds estimated spare time of 10581.000; restart ...
> delay of 24749.000 usecs exceeds estimated spare time of 10581.000; restart ...
> 
> Is that related?

Yes, probably, those are excesive delays in scheduling. 

Another point is that jackstart is not needed for 2.6.x kernels, it will
complain about the capabilities stuff but will work anyway. Try
replacing "jackstart" with just "jackd". 

-- Fernando