Followup British Telecom outage reason

Alex Bligh alex at
Sat Dec 1 13:50:52 UTC 2001

--On Wednesday, 28 November, 2001 11:39 PM -0500 Christian Kuhtz 
<christian at> wrote:

> Don't use a non-realtime OS for something that you expect realtime or
> near-realtime OS functionality.  There are specific systems to address
> these kinds of needs with rather complicated scheduling mechanism to
> accomodate such requirements in a sensible manner.
> Is IOS a realtime operating system?  No.  Are any of the other listed OS
> realtime operating systems?  No.  (The (*) doesn't count).   Do I wish
> some of these clowns would use sophisticated realtime OS?  Yes.  Will it
> solve world hunger?  Decidedly not.

One of us has the wrong end of the stick. My point was
that the requirement for some of the basic functionality of
preemptive multitasking, and (near) real time performance,
is rather more necessary in a router,
where one tends to have a requirement to run multiple instances
of multiple protocols in a time dependent manner, schedule
queues etc. etc., than in a desktop or server operating system.
However, this doesn't correspond to how one or two router OS's
are actually designed.

Alex Bligh
Personal Capacity

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