Followup British Telecom outage reason

Youse, Chuck Chuck.Youse at
Thu Nov 29 08:20:59 UTC 2001

You'll forgive me for being cynical here, but I seriously doubt that any
Linux-derived operating systems could truly qualify as 'real-time'.  To meet
the requirements for an RTOS, Linux would have to be so heavily mutated that
it would no longer be Linux.


-----Original Message-----
From: Patrick Greenwell
To: Christian Kuhtz
Cc: Alex Bligh; Paul Vixie; nanog at
Sent: 29/11/01 07:49
Subject: RE: Followup British Telecom outage reason

On Wed, 28 Nov 2001, Christian Kuhtz wrote:

> > I guess some time someone will realize routers are both
> > hardware, and software, and shock horror both, if done
> > well, can actually add value. [hint & example: compare the
> > scheduler on, say, Linux/FreeBSD, Windows 95 (sic),
> > and your favourite router OS (*); pay particular attention
> > to suitability for running realtime, or near realtime tasks,
> > where such tasks may occasionally crash or overrun their
> > expected timeslice; note how the best OS amongst the
> > bunch for this aint exactly great].
> >
> > (*) results may vary according to personal choice here.
> Don't use a non-realtime OS for something that you expect realtime or
> near-realtime OS functionality.  There are specific systems to address
> kinds of needs with rather complicated scheduling mechanism to
> such requirements in a sensible manner.
> Is IOS a realtime operating system?  No.  Are any of the other listed
> realtime operating systems?  No.

Actually there are multiple Linux-based RTOSes.

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