Re: [ANNOUNCE] Adeos nanokernel for Linux kernel

Peter Wächtler
2002-06-05T11:09:32Z

Daniel Phillips wrote:
> On Tuesday 04 June 2002 21:29, Oliver Xymoron wrote:
>
>>On Mon, 3 Jun 2002, Daniel Phillips wrote:
>>
>>
>>>traditional IT. Not to mention that I can look forward to a sound
>>>system where I can be *sure* my mp3s won't skip.
>>>
>>Not unless you're loading your entire MP3 into memory, mlocking it down,
>>and handing it off to a hard RT process. And then your control of the
>>playback of said song through a non-RT GUI could be arbitrarily coarse,
>>depending on load.
>>
>
> Thanks for biting :-)
>
> First, these days it's no big deal to load an entire mp3 into memory.
>
> Second, and of more interest to broadcasting industry professionals and the
> like, it's possible to write a real-time filesystem that bypasses all the
> normal non-realtime facilities of the operating system, and where the latency
> of every operation is bounded according to the amount of data transferred.
> Such a filesystem could use its own dedicated disk, or, more practically, the
> RTOS (or realtime subsystem) could operate the disk's block queue.
>
> If I recall correctly, XFS makes an attempt to provide such realtime
> guarantees, or at least the Solaris version does. However, the operating
> system must be able to provide true realtime guarantees in order for the
> filesystem to provide them, and I doubt that the combination of XFS and
> Solaris can do that.
>
>

It's XFS with a realtime volume under Irix.
With the React extension Irix is also capable of "hard realtime".
But these days the term realtime is a lot misused - and leeds to
assumption of a better "system".