Jaunty Alpha 5 and linux-rt (ppa)

alex stone compose59 at gmail.com
Sun Mar 8 12:03:43 GMT 2009

On Sun, Mar 8, 2009 at 2:42 PM, Asmo Koskinen <asmo.koskinen at arkki.info>wrote:

> alex stone kirjoitti:
> > Asmo,
> > do you need capture ports?
> I'm no expert here with jackd - do you mean recording - yes, I need that
> feature, I need record voice and instruments via jackd/Ardour2.
> > And would 3 periods work better than 2?
> I just try to clone my working Hardy environment on Jaunty, I use these
> options on Hardy.
> "studio at ubuntu-studio:~$ cat .jackdrc
> /usr/bin/jackd -R -dalsa -dhw:0 -r44100 -p256 -n2
> studio at ubuntu-studio:~$"
> http://wiki.ubuntu-fi.org/Ubuntu_Studio#head-d170ac730326977ff551a2b83fca37c1a9c53de9
> Best Regards Asmo Koskinen.
> --
> Ubuntu-Studio-users mailing list
> Ubuntu-Studio-users at lists.ubuntu.com
> Modify settings or unsubscribe at:
> https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-users


if you change -n2 to -n3 and try that, it may help. It depends on how low
you want latency to go, but i'm one who sometimes thinks the 'obession' with
ultra low latency is a bit self defeating. I sat in an orchestra for some
time (woodwinds), and experienced quite a bit more than 5ms latency between
me and the 1st violins. One learns to compensate. Maybe with 10-15ms
latency, and a bit of 'instinctive user compensation' the end result may be
better than one would think.

Having said this, on 64bit Hardy UBStudio, i'm writing with an average of
8-10ms (non-live. I write in the box, so to speak), and on my new Debian 5
32bit build, with a self baked RT kernel (2.6.26-rt11), i'm getting 5-10ms
dependent on task, comfortably, and importantly, with all day everyday

Previous testing, and i say this from a strictly personal perspective, had
Gutsy UBStudio yielding the best results, with latency (tested for the fun
of trying) as low as 3ms (stable).

My soundcard is an Maudio Delta 44, with the ice1712 Alsa module.

I don't use oss at all, and turned it off in the debian kernel build.

I use raw as the midi driver, and a2jmidid for any cross alsa/jack midi

limits are:

audio nice -19
rtprio 99
memlock unlimited

pidirq for the soundcard is set at a priority of 92
jack priority is set to 89

the computer is an AMD dualCore x64 5600+ with 4gb of ram.
3 HD, being 1 system, and two dedicated sample drives.
Additional external drive for backup.

All 7200, 32mb cache.

Maybe something you see in this might help.

*Note* In the settings you provided for jack, i notice you don't have a
defined priority number for realtime, just an -R flag. Is there a reason for


Parchment Studios (It started as a joke...)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://lists.ubuntu.com/archives/ubuntu-studio-users/attachments/20090308/f86f56d5/attachment.htm 

More information about the Ubuntu-Studio-users mailing list