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Date: Tue, 12 Jan 1999 14:09:28 +0100
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From: Stephen Thornton <Stephen.John.Thornton@ericsson.no>
To: Thomas Sailer <sailer@ife.ee.ethz.ch>
Cc: Stephen Thornton <Stephen.John.Thornton@ericsson.no>,
        alsa-devel@alsa.jcu.cz
Subject: Re: Linux scheduler issues.
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Thomas Sailer writes:
 > Stephen Thornton wrote:
 > 
 > > I assume you are talking about RTLinux here. OK, as you show, you can
 > > stop everything except
 > 
 > No I was talking about less than 2 year old vanilla Linux.

OOPS! Had my head inside embedded systems too long.

 > 
 > > I'll state my position: I am at least going to persue a feasibility
 > > study on the use of Erlang in music. I will point out the advantages
 > 
 > But the choice of language is pretty orthogonal to the issue of how
 > to meet the deadlines 8-)
 >
I think this is the start of a new thread, I'll answer this
seperately.
 
 > My point is: I'm currently doing usermode network interface stuff.
 > One project uses the soundcard to do IO, and contains a software
 > modem. This app in structure is probably very similar to
 > a synthesizer engine except for the smaller memory footprint 8-)
 >
Project I'm working on has a realtime os, running annother realtime os
as a single process, talking to 6 DSPs running software modems. This
is a real pain, but it's NOT Linux. An example of how to make life
difficult for oneself.

 > It's very seldom that an interrupt/wakeup is delayed by more than one
 > sample period (roughly 100us). I think I have to start
 > gathering long term statistics.
 > 
 > So my point is: In how far do computer music apps differ from
 > my modem stuff? And given that my modem stuff works, why
 > all the fuzz about the scheduler? Has anyone actually tried and
 > had problems?
 >
Good point. Depends what you want to do though. If you just want a
sequencer/sampler with simple playlists fine. Maybe I am a lot more
ambitious than that. I'll try and explain what I have in mind, but
I'll keep it general. I'll write this seperately as it does have some
bearing on the language issue alluded to above.

cheers
Steve

