hi hvaartsen,
standard Ubuntu 9.10 installation on Dell XPS m1330 2gb T5250
w/separate partition for /home
setup the desktop however you want -- i disable unnecessary services (e.g., i don't use bluetooth or evolution, including the clock/calendar applet). i have installed gnome-do and configured it to be like the MacOSX dock -- very cool and functional.
system > administration > users and groups > add your user to "audio" and "video" groups
https://help.ubuntu.com/community/UbuntuStudioControls
https://help.ubuntu.com/community/FireWire -- ignore rtirq for now (see below)
edit /etc/security/limits.conf to add the following line if it doesn't exist -- the other two parameters (memlock and nice) should be there from UbuntuStudio Control
"@audio - rtprio 95" or similar priority
my rtprio is 85 and nice is -15. with rtprio and nice i worry about audio competing with essential system processes if i set them too high, so this is good middle ground for me
gnome panel: right click, add cpufreq scaling monitor applets x 2
use these to enable "performance mode" on both cores. In Pianoteq this gives me 15-20% more CPU headroom. when i am finished with audio work, i just change it back to "ondemand" to save power/heat/battery life. also helpful to close firefox and disable networking (software AND hardware kill switch) during audio work.
the last step would be to add the linux-rt kernel and install and setup rtirq:
http://ubuntuforums.org/showthread.php?t=1328175
i haven't installed a the linux-rt kernel yet. two questions i have about the linux-rt kernel: 1. does it allow cpu freq scaling? 2. can i suspend/hibernate my computer with it? even if it doesn't, i may still install it and install/configure rtirq in case i need better performance, so i can reboot with the linux-rt kernel as necessary, e.g., when i do more recording work/longer sessions.
after setup is done, install whatever programs you need (jackd, qjackctl, ffado, etc) and configure them appropriately. i can run Pianoteq with either ALSA backend (Intel HDA 2.0 integrated soundcard -- sounds great!) or JACK backend. With jack, i can use either ALSA or FFADO (firewire) for my AudioFire2 sound card. Full access to soundcard settings via ffado-mixer.
qjackctl automatically suspends PulseAudio, so there is no hardware conflict. Normal audio resumes when exiting qjackctl. the bonus is higher JACK performance. on the other hand, if there is ever an option to allow JACK to exist on top of PulseAudio, then you can play/record from ANY sound-generating application (think: mplayer, firefox/youtube, rhythmbox) with JACK. i haven't gotten this to work, but am not sure i want/need it.
at any rate, this beats a dual-boot setup by far! all my files and programs are in one convenient location with minimal interruption in work flow