Le 17/10/2011 21:43, Edward Diehl a écrit : Hi Edward, sorry for the long book, it may help ? http://www.restivo.org/blog/archives/sanity-checking-rtirqs upthere a link that you may like, to dig, and down some useful commands, they are the kind of 'howto-reminder' made for the "ok, let's format /, I f***** it up again" man than I am !! For your DSP excessive use, you may pay attention to : -never use PulseAudio, have only ALSA (and Jack)))) -check if Jack settings and IRQ prios are ok -killall services and daemons that you don't use for making music (web, print, automount, bluetooth...) -not share IRQ with video -record audio (Ardour session in fact) in another HD than programs if you can -use a light weight WM (Gnome or Kde are too much "power eaters") Let me know, I think about trying AVLinux soon (next f***** up near I feel))) and like to read your advice on it with some settings done !! HTH, Good luck, Fred # commands # ulimit -l will tell you how much memory you can lock ulimit -r will tell you at what realtime priority you can run software uname -r will tell which kernel is on use lspci list the chips lsmod list modules loaded at boot dmesg read the bootlog lsi -v|grep audio list audio chipset ps -eo cmd,rtprio will list all the realtime priorities for all your tasks # maybe too much services started ? ls /etc/rc2.d list daemons started at boot # 2.6.29-rt1 = good kernel for P4! # Maybe you share an IRQ with video ?? ps -eo cmd,rtprio will list all the realtime priorities for all your tasks cat /proc/asound/cards will show the IRQs for your cards cat /proc/interrupts list IRQs # RT prio goes like this : 99 watchdog 90 sound card 80 ALSA 70 Jack 60 Ardour # at the end of /etc/security/limits.conf (depending your distro, sometimes elsewhere or autogenerate when install Jack) add the following (with sudo gedit ie) @audio - rtprio 99 @audio - memlock unlimited #@audio - nice 10 #nice value has nothing to do with real time or latency, forget it ! # jack settings I record tracks in Ardour with these Jack settings, and it was fine : -R -P89 -p128 -dalsa -dhw:0 -r48000 -p128 -n3 -D -Pplughw:0 -i2 -o2 -Xseq Then I try to mix with many plugins, and due to the "formidable" PC I use, Ardour don't want to do anything... So, thanks Ralf, I fixed QJackCtrl settings to : -R -P89 -p128 -dalsa -dhw:0 -r48000 -p512 -n2 -D -Pplughw:0 -i2 -o2 # you can record several settings in QJackCtl...