Hello Toby,

I've been running Csound in realtime under Linux for some time and
haven't found big issues with the latency (although I sometimes have
to use higher latency in order to get more CPU power due to the kind
of processing I do). In any Linux system you have to use a realtime
kernel if you want to have low latency (and there is big benefit from
using it) but also you mention you had better results before (and I
assume you weren't using a RT kernel).

Also if you used Jack instead of Alsa you could expect to get much
better latency. Is there any reason why you are not using Jack? Also I
recommend you to try to get the RT kernel running. Are you
experiencing hard locks when using it? (but this might be topic for a
different list).

Cheers,

Hector


On Fri, Oct 24, 2008 at 6:50 PM, Tobiah <toby@tobiah.org> wrote:
> Hi, it's been a while!
>
> I've been off csound for at least a year, probably more.
> It's always on my mind though, and circumstances permit
> that I am able to delve back in for a while.
>
> I remember getting rather astonishingly low latency controlling
> csound from my midi keyboard in the past.  I've made a new simple example,
> and
> am finding that I have to set buffer sizes to around 8192 samples
> to avoid buffer underruns!  Needless to say, this is too slow
> for keyboard playing.
>
> I'm on a fairly quick machine, running kubuntu 8.04.  I tried
> installing the realtime kernel, but there doesn't seem to be
> any benefit from booting it, and it invariably crashes after a while.
>
> Can anyone see what I might be missing, or suggest any tweaks
> to try?  Under the below example, I get constant
> "WARNING: Buffer underrun in real-time audio output"
> They don't go away until I use huge buffer values.
>
> I've achieved beautiful results on this box previously,
> but with a different installation.
> Thanks,
>
> Toby
>
> The soundcard is an echo Mia MIDI.
>
> **Csound version 5.08 (double samples) Apr 16 2008
>
> **CPU:          Intel(R) Core(TM)2 CPU @ 1.86GHz
>
> **Command line:
>
> sudo csound\
>             -+rtaudio=alsa\
>             -+rtmidi=alsa\
>             -o dac\
>             -d\
>             --midi-device=hw:0,0\
>             -B 512 -b 256 --sched\
>             --midi-key-cps=5\
>             --midi-velocity-amp=4\
>              orc sco
>
> **Orchestra:
>
> sr = 44100
> ksmps = 100
> nchnls = 2
>
> instr 1
>
>     aPitch init p5 * .5
>
>     asigl  oscil p4, aPitch, 1
>     asigr  oscil p4, aPitch + 1, 1
>     outs    asigl, asigr
>
> endin
>
>
> **Score:
>
> f1 0 65536 10 1 .5 .25 .125
> f2 3600
>
>
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
> csound"
>