Subject: Re: Floating point in the kernel
To: John F. Woods <>
From: Curt Sampson <>
List: tech-kern
Date: 09/21/1998 14:48:19
On Sat, 19 Sep 1998, John F. Woods wrote:

> > Well, not exactly. I don't see why a hard real-time system can't
> > say `nobody gets more than 80% of the CPU, ever.' It's the equivilant
> > of putting a slower CPU in the machine.
> A hard real-time can't say that because real-time isn't about
> performance.  Real-time is about *predictable response time*, and
> refusing to schedule a real-time task for some period of time just
> because it has been busy means it will blow its response deadline.

How is this different from blowing a response deadline because
another scheduled real-time task ate up so many system resources
that the first one didn't get to execute by its deadline? As I
understand it, if your CPU is too slow, it's too slow, and there's
nothing you can do about it. I'm just proposing artifically `slowing
down' the CPU.

Curt Sampson  <>  604-257-9400    De gustibus, aut bene aut nihil.
Any opinions expressed are mine and mine alone.
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