Re: What is real-time?

"Andor" <andor.bariska@xxxxxxxxx> writes:

Randy wrote:

A real-time system is a system that has a period and a well-defined
maximum amount of work to be done in that period and that can perform
that amount of work in that period.

Latency is input to output delay.

Now think about it: the work a system does is to transform an input
into an output. And the "period" limits the amount of time that the
system may spend on the work, ie. the amount of time the system has
available to transform an input into an output. So, by your
definition, a real-time system is a system that has bounded input/
output latency.

Oh yeah. Hmmm. That's true, Andor. I agree. The two specifications
(that is, fixed-latency and deadline-meeting) are equivalent.

I guess I meant that requiring any *specific* amount of latency is a
separate issue than requiring a system to be real-time.

After I re-read Steve's post, I believe I'm just repeating his point:
The actual latency is completely undefined. The only requirement is
that the maximum latency (whatever it may be) is fixed.
--
% Randy Yates % "Though you ride on the wheels of tomorrow,
%% Fuquay-Varina, NC % you still wander the fields of your
%%% 919-577-9882 % sorrow."
%%%% <yates@xxxxxxxx> % '21st Century Man', *Time*, ELO
http://home.earthlink.net/~yatescr
.

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