From alsa-devel-owner@alsa.jcu.cz  Sun Feb 28 22:59:27 1999
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Date: Sun, 28 Feb 1999 13:55:02 -0800
To: alsa-devel@alsa.jcu.cz
From: "Kevin Duffey" <kduffey@inprise.com>
Subject: Re: New proposal: Timer interface
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I have a question about timing. Being from the MS Windows environment,
Win95/98 are TERRIBLE at timing. Mostly because of the multi-task switching
it does. It turns out normal task switching is done at 20ms intervals for
each task running. If a music app that requires timing down to 1 ms for
events, audio sync, midi sync, etc, you can forget about real-time syncing.
I have seem some midi apps with audio in it do a lot of skipping.

So my question is...does Linux have this same problem? Or is the timing
considerably much better even while a few apps run? Ultimately, a sequencer
that allows audio and MIDI intermixed with real-time DSP effects and auio
channels should not have many apps running at the same time for best
performance. But..I am just wondering how the timing is achieved in linux
for such apps? Is their system or multimedia support built in to allow very
accurate timing? Or like MS Windows is it pretty much impossible to get
accurate timing?  The way MS Windows does it is to write 16-bit win3.1 code
that does the low-level multimedia stuff, and the 32-bit app "thunks" to
use that 16-bit code.

thanks.

Kevin Duffey
kduffey@inprise.com

