[PlanetCCRMA] Jack, Jackd and realtime problem

[Shayne O'Connor]

Fernando Lopez-Lezcano wrote:

>On Fri, 2005-02-18 at 11:48, Shayne O'Connor wrote:
>  
>
>>Ben Cohen wrote:
>>    
>>
>>>I think I'm having a problem with Jack. I use the
>>>jackd server but when I have the realtime box checked
>>>in qjackctl amsynth doesn't start.
>>>
>>>Here's the jack message:
>>>12:19:41.406 MIDI connection graph change.
>>>subgraph starting at qjackctl-4757 timed out
>>>(subgraph_wait_fd=17, status = 0, state = Finished)
>>>12:19:41.445 Audio connection graph change.
>>>12:19:41.446 XRUN callback (5).
>>>**** alsa_pcm: xrun of at least 8.616 msecs
>>>
>>>>From what I can gather realtime priority is a must for
>>>good audio performance so I any help on solving this
>>>would be great.
>>>
>>>I'm using kernel 2.6.10-2.1.ll.rhfc3.ccrma.
>>>
>>>This is the second time I've had problems with amsynth
>>>- it always amazes me how an inanimate object can get
>>>someone (i.e. me) so frustated!
>>>      
>>>
>>i'm getting a similar problem - i can run amSynth with alsa as output,
>>    
>>
>
>Same here, it looks like it is related to Jack output. 
>
>  
>
>>but using jack produces this:
>>
>>[mrmachine@localhost mrmachine]$ amSynth
>>amSynth 1.0.0
>>Copyright 2001-2004 Nick Dowell and others.
>>amSynth 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
>>reading map file
>>        unlocking /usr/lib/libgtk-1.2.so.0.9.1
>>        unlocking /usr/lib/libgtk-1.2.so.0.9.1
>>        unlocking /usr/lib/libgtkmm-1.2.so.0.3.4
>>        unlocking /usr/lib/libgtkmm-1.2.so.0.3.4
>> 
>>GLib-WARNING **: getpwuid_r(): failed due to: No such user 500.
>> 
>>Gtk-WARNING **: /usr/lib/gtk/themes/engines/libbluecurve.so: failed to
>>map segment from shared object: Resource temporarily unavailable
>>/usr/bin/amSynth: line 75:  7830 Aborted                
>>$BINDIR/amSynth.bin $*
>> 
>>********** there was an error! **********
>> 
>>please check your config in ~/.amSynthrc
>>
>>I'm not sure where this supposed "user 500" is set?
>>    
>>
>
>I don't know either. It runs in rh9 but rh9 still has an older
>(official) version of jack...
>
>[... minutes later ...]
>
>Ok, I think I know (or can guess). This is probably a selinux problem.
>The amSynth binary is really in /usr/libexec/amSynth.bin and is
>installed suid (probably should not). Something in the security
>framework does not like you to execute it like that and fails. Do a:
>
>  chmod 755 /usr/libexec/amSynth.bin
>  
>
yep - that works. also, it doesn't seem to effect real-time response
under alsa output ....

shayne