[PlanetCCRMA] Jack with YMFPCI

Fernando Pablo Lopez-Lezcano nando@ccrma.Stanford.EDU
Sat Aug 23 11:29:01 2003

> Seeing that is was a problem with both playback and capture I tried increasing the
> number of periods to 3, which seemed to be an improvement. 
> Unfortunately this did not solve all the problems, as I got this:
> [root@localhost root]# jackd -v -d alsa -d hw:0 -P -n 3
> jackd 0.72.4
> Copyright 2001-2003 Paul Davis and others.
> jackd comes with ABSOLUTELY NO WARRANTY
> This is free software, and you are welcome to redistribute it
> under certain conditions; see the file COPYING for details
> 1233 waiting for signals
> JACK compiled with System V SHM support
> running with uid=0 and euid=0, will not try to use capabilites
> loading driver ..
> new client: alsa_pcm, id = 1 type 1 @ 0x80586d0 fd = -1
> creating alsa driver ... hw:0|hw:0|1024|3|48000|nomon|swmeter|rt
> open
> jackd: pcm.c:5946: snd_pcm_mmap_begin: Assertion `pcm && areas && offset && frames' failed.
> received signal 6 during shutdown (ignored)
> What is the problem here?  Is it ususally necessary to run with the periods 
> set to 3 for my computer/card setup?

I think that's the case, you are on the right track. Try to make sure
that no instances of jackd are running when you try to start it again.
Sometimes when it has problems it does not die gracefully and some
processes are left behind that mess up the next startup. Try: "ps
axuw|grep jackd" to see if there is anything left behind, kill it and
restart jackd. 

BTW, if you installed the Planet CCRMA kernel you can run jack with
realtime scheduling as a normal user (no need to be root) using the
jackstart command. 

-- Fernando