Re: a joint letter on low latency and Linux

[Rogier Wolff]

Larry McVoy wrote:
> > if you're going to define *any* guaranteed response as "hard
> > realtime", be my guest. you might even be right.
> 
> That would be the commonly accepted definition in the literature and in
> practice for the last 30 years or so.  Actually, it's closer to "any
> requirement for a response that must happen in any fixed interval of
> time".  Hard real time has nothing to do with how long the interval is,
> it has everything to do with not missing the deadline.

So?  Audio playback is hard-realtime: If I submit the audio for the
next two seconds to the kernel, I have a 2-second deadline for
generating the next batch. 

We'd like Linux to be a system where it is reasonably able to perform
audio playback. I mean when 5% of my CPU suffices to do the MP3
decompression, I should be able to listen to an MP3 while I do other 
stuff with my Linux workstation. 

In short: we need hard-realtime in the mainstream Linux kernel. 

			Roger.

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