testing Kxstudio 12.04 with firewire

[alessandro]

Hello,

I will try to describe my experience (...be patience for my english):
I installed Kxstudio i386 from ubuntustudio (fresh install as Falk's instructions) in external usb-HD to test it.
(In my HD internal run good Kxstudio 10.04 -64bit with kernel 2.6.32.40/41preempt with noveau video driver).

My setup is HP dv6 2193el FA-66, usb Nanokontrol, usb ikon key.

-I updated system 30 minutes ago.
-Startup with kernel 3.2.0-24-generic-pae (the system load NVidia driver and broadcom internal wifi, not in my normal system 10.04)
-run Kxstudio welcome
-reboot
-start cadence in syncronous mode, cadence default is set with alsa, it run good with internal HDA intel.
-start jack, and lady tool

Then i change parameter to drive firewire in this order: cadence, jack, lady configuration tool (stop-start studio):
-I start cadence with 44100Hz, 512 frame, 3 periods, it's ok, then i lowered frame to 256, reset FA-66 and force restart, In the same way lowered frame finally to 128, that is the configuration i run in my normal studio (Kx 10.04).
-I must manually start a2J in cadence each time i force restart it (in my normal studio it start automatically restarting cadence).
-This is the only mode to avoid cadence crash changing parameters:

Code: Select all

Thu May 10 21:39:48 2012: Controller activated. Version 1.9.8 (unknown) built on Sat May  5 20:59:50 2012
Thu May 10 21:39:48 2012: Loading settings from "/home/alessandro/.config/jack/conf.xml" using expat_2.0.1 ...
Thu May 10 21:39:48 2012: setting parameter 'engine':'driver':'(null)' to value "firewire"
Thu May 10 21:39:48 2012: setting parameter 'engine':'realtime':'(null)' to value "true"
Thu May 10 21:39:48 2012: setting parameter 'engine':'sync':'(null)' to value "true"
Thu May 10 21:39:48 2012: setting parameter 'drivers':'firewire':'period' to value "128"
Thu May 10 21:39:48 2012: setting parameter 'drivers':'firewire':'rate' to value "44100"
Thu May 10 21:39:48 2012: setting parameter 'drivers':'alsa':'rate' to value "44100"
Thu May 10 21:39:48 2012: setting parameter 'drivers':'alsa':'period' to value "256"
Thu May 10 21:39:48 2012: setting parameter 'internals':'audioadapter':'rate' to value "44100"
Thu May 10 21:39:48 2012: setting parameter 'internals':'audioadapter':'periodsize' to value "128"
Thu May 10 21:39:48 2012: setting parameter 'internals':'audioadapter':'nperiods' to value "3"
Thu May 10 21:39:48 2012: Listening for D-Bus messages
Thu May 10 21:39:52 2012: Starting jack server...
Thu May 10 21:39:53 2012: JACK server starting in realtime mode with priority 10
Thu May 10 21:39:53 2012: ERROR: firewire ERR: FFADO: Error creating virtual device
Thu May 10 21:39:53 2012: ERROR: Cannot attach audio driver
Thu May 10 21:39:53 2012: ERROR: JackServer::Open() failed with -1
Thu May 10 21:39:53 2012: ERROR: Failed to open server

System seems run but i have a lot of xruns (37 in 10 minutes).
the xruns count is not the same in cadence and jack (now 84-52)

With lowlatency kernel, cadence do not start with firewire, same with realtime kernel (error ffado time out).
With realtime the video run in low resolution (not NVidia driver).

-I would like to investigate about trehadirq.

Soon other things, once I get time

Alessandro

[falkTX]

hey there, thanks for your interest on KXStudio
sadly, I do not own any firewire cards (my computer doesn't even have a FW port).

from what I've seen over the years, some of your configuration is probably not 100% correct, causing xruns (perhaps period-size should be '2' or maybe even '4' ?)

I'm really not the right guy to give advice regarding firewire.
any firewire users here want to comment on this?

[alessandro]

hi Falk,
I decided for 3 period after reading a post of autostatic some time ago.
I right tested 2 and 4 period instead 3 on my normal system (Kx 10.04), actually 44100, 128, 4 seems the best mix, less xruns!

Latency is now 11.6 msec instead of 8.71 in jack but remains 2,9 ms in cadence (same as previous configuration).
Why difference between jack and cadence?

I'll test it on Kx 12.04 soon

thanks for the reply!
Alessandro

[falkTX]

Why difference between jack and cadence?

jack doesn't have a gui to report latency. are you referring to qjackctl ?

if that's the case, it's simply because we calculate the latency in different ways.
afaik, both are wrong, they are just estimates.