Es comun tener xruns?

Hola a todos miren estoy experimentando en una laptop hp 530 core duo de 2.16 ghz y 2gb ram....
le e instalado ubuntustudio 8.04 pero tengo la siguiente duda..... e empezado a configurar mi jack con la tarjeta de mi lap...... esto es lo que he hecho:

Frames/Period: 1024 :S
Sample Rate: 48000
Periods Bufer: 3
Real time encendido y tambien forzar a 16 bits....
Esto me da una latencia de 64 ms

Le doy start y no tengo ningun xrun...... sin hacer nada de nada no salen xruns.. me pongo a navegar en internet actualizar bajar cosas y no se mueve..... pero cuando empiezo a trabajar con ardour salen xruns.....sale algo como: 4(108)

Y los mensajes disen algo como esto:

14:42:53.658 Patchbay deactivated.
14:42:53.745 Statistics reset.
14:42:53.801 ALSA connection graph change.
14:42:53.965 ALSA connection change.
14:43:25.170 Startup script...
14:43:25.171 artsshell -q terminate
14:43:25.887 Startup script terminated with exit status=256.
14:43:25.888 JACK is starting...
14:43:25.888 /usr/bin/jackd -R -P70 -p128 -t5000 -dalsa -dhw:0 -r48000 -p1024 -n3 -S
14:43:25.890 JACK was started with PID=6197.
jackd 0.109.2
Copyright 2001-2005 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
JACK compiled with System V SHM support.
cannot lock down memory for jackd (Cannot allocate memory)
loading driver ..
apparent rate = 48000
creating alsa driver ... hw:0|hw:0|1024|3|48000|0|0|nomon|swmeter|-|16bit
control device hw:0
configuring for 48000Hz, period = 1024 frames (21.3 ms), buffer = 3 periods
ALSA: final selected sample format for capture: 16bit little-endian
ALSA: use 3 periods for capture
ALSA: final selected sample format for playback: 16bit little-endian
ALSA: use 3 periods for playback
JACK: unable to mlock() port buffers: Cannot allocate memory
JACK: unable to mlock() port buffers: Cannot allocate memory
14:43:28.902 Server configuration saved to "/home/ubaldo/.jackdrc".
14:43:28.903 Statistics reset.
14:43:28.905 Client activated.
14:43:28.906 JACK connection change.
14:43:28.909 JACK connection graph change.
cannot lock down memory for RT thread (No se puede asignar memoria)
14:46:35.183 ALSA connection graph change.
14:46:35.333 ALSA connection change.
14:46:36.527 JACK connection graph change.
14:46:44.418 JACK connection graph change.
14:46:44.789 JACK connection graph change.
14:46:44.948 JACK connection change.
14:47:05.629 XRUN callback (1).
delay of 20337.000 usecs exceeds estimated spare time of 19927.000; restart ...
delay of 20337.000 usecs exceeds estimated spare time of 19927.000; restart ...
delay of 20312.000 usecs exceeds estimated spare time of 19927.000; restart ...
delay of 20318.000 usecs exceeds estimated spare time of 19927.000; restart ...
delay of 20335.000 usecs exceeds estimated spare time of 19927.000; restart ...
delay of 20335.000 usecs exceeds estimated spare time of 19927.000; restart ...
delay of 20344.000 usecs exceeds estimated spare time of 19927.000; restart ...
delay of 20344.000 usecs exceeds estimated spare time of 19927.000; restart ...
delay of 20324.000 usecs exceeds estimated spare time of 19927.000; restart ...
delay of 20333.000 usecs exceeds estimated spare time of 19927.000; restart ...
delay of 20333.000 usecs exceeds estimated spare time of 19927.000; restart ...
delay of 20334.000 usecs exceeds estimated spare time of 19941.000; restart ...
delay of 20334.000 usecs exceeds estimated spare time of 19941.000; restart ...
delay of 20339.000 usecs exceeds estimated spare time of 19941.000; restart ...
delay of 20339.000 usecs exceeds estimated spare time of 19941.000; restart ...
delay of 20310.000 usecs exceeds estimated spare time of 19941.000; restart ...
14:47:07.356 XRUN callback (15 skipped).

Quisiera saber si esto es normal..... o si nececita aumentar el Frames/Period a 2024 o talves el Period/Bufer subirlo hasta 4 o el Sample rate usarlo en 41000

Gracias, Saludos.

Si miras las trazas de Jack, aparece esto...

"cannot lock down memory for RT thread (No se puede asignar memoria)"

Esto quiere decir seguramente que no tengas permisos para allocatar memoria para procesos en tiempo real.

Tu usuario pertenece al grupo audio? Si no es así, debería

salud!

mmmmm........ no lo se realmente........me instale ubuntustudio 8.04 y solo trabajo con la cuenta de usuario que me creo al inicio.......... debo configuarar la cuenta de alguna manera en especial para eso????.......

Te hablo de memoria, así que los nombres de las opciones puede que no sean exactamente esos, pero tienes que ir al menú de Ubuntu Studio -> Sistema -> Administración -> Usuarios. Te saldrá una ventanita pequeña con todos los usuarios creados (tendrás dos: root, y el tuyo). Tienes que pinchar en la opción "Desbloquear", le pones la contraseña del root, seleccionas tu usuario y le das a "Administrar grupos". Te salen dos listas, la de los grupos existentes a la izquierda, y la de los grupos a los que pertenece el usuario a la derecha. Simplemente seleccionas audio en la de la izquierda y la agregas.

ubaldo@ubuntu:~$ cat /etc/group | grep audio
audio:x:29:pulse,ubaldo

pongo esto en la terminal para saber si estoy en el grupo de audio y parese que ya..... el errror de la memoria esta solucionado pero aun sigo teniendo estos:

tengo: frames/period 512 samplerate: 48000 Periods/bufer: 4


21:38:32.949 Patchbay deactivated.
21:38:33.024 Statistics reset.
21:38:33.056 ALSA connection graph change.
21:38:33.231 ALSA connection change.
21:38:34.794 Startup script...
21:38:34.796 artsshell -q terminate
21:38:35.219 Startup script terminated with exit status=256.
21:38:35.219 JACK is starting...
21:38:35.220 /usr/bin/jackd -R -P70 -p128 -t5000 -dalsa -dhw:0 -r48000 -p512 -n4 -S
21:38:35.222 JACK was started with PID=8171.
jackd 0.109.2
Copyright 2001-2005 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
JACK compiled with System V SHM support.
loading driver ..
apparent rate = 48000
creating alsa driver ... hw:0|hw:0|512|4|48000|0|0|nomon|swmeter|-|16bit
control device hw:0
configuring for 48000Hz, period = 512 frames (10.7 ms), buffer = 4 periods
ALSA: final selected sample format for capture: 16bit little-endian
ALSA: use 4 periods for capture
ALSA: final selected sample format for playback: 16bit little-endian
ALSA: use 4 periods for playback
21:38:38.246 Server configuration saved to "/home/ubaldo/.jackdrc".
21:38:38.247 Statistics reset.
21:38:38.273 Client activated.
21:38:38.274 JACK connection change.
21:38:38.277 JACK connection graph change.
**** alsa_pcm: xrun of at least 20.319 msecs
21:38:47.478 XRUN callback (1).
21:38:52.448 XRUN callback (2).
delay of 41656.000 usecs exceeds estimated spare time of 10504.000; restart ...
21:38:53.824 XRUN callback (3).
delay of 9625.000 usecs exceeds estimated spare time of 9607.000; restart ...
delay of 9625.000 usecs exceeds estimated spare time of 9607.000; restart ...
delay of 9612.000 usecs exceeds estimated spare time of 9607.000; restart ...
delay of 9612.000 usecs exceeds estimated spare time of 9607.000; restart ...
21:38:54.489 XRUN callback (4 skipped).
delay of 9649.000 usecs exceeds estimated spare time of 9607.000; restart ...
delay of 9649.000 usecs exceeds estimated spare time of 9607.000; restart ...
21:38:56.494 XRUN callback (1 skipped).
21:39:01.539 Client deactivated.
21:39:01.541 JACK is stopping...
jack main caught signal 15
no message buffer overruns
21:39:01.589 JACK was stopped successfully.
21:39:01.589 Post-shutdown script...
21:39:01.590 killall jackd
jackd: ningún proceso eliminado
21:39:01.998 Post-shutdown script terminated with exit status=256.

Gracias por sus respuestas......