Re: Ada Microkernel?

["Marin David Condic" <marin.condic.auntie.spam@pacemicro.com>]

My OS book from back in my college days is so old, I don't think it would be
anywhere close to up to date with modern OS theory. That's why I'm asking
for a recommendation.

I'd agree that an RTOS and a "Workstation" OS are going to have
fundamentally different design goals. However, I don't know that down at a
low level, you couldn't find some common ground and make the rest somehow
"switch selectable" IOW, it would be useful to make WindowsNT have a
"Real-Time"  mode so you could run critical processes on it, yet have all
the tools & services available to you that programming in non-real-time
usually does. Indeed, there are third-party products to do just that. (From
what I've seen, they tend to duplicate most of the Windows API, put a RTOS
under it, then run Windows as a lower priority process.)

I think the biggest area of contention between the two would be the
scheduler. I don't see how things like device drivers, interrupt processing,
etc., would be of necessity incompatible. (The non-real-time could use
real-time algorithms without penalty to the end user if its done reasonably.
The real-time guys just need predictability.) But wouldn't it be possible to
specify more than one scheduling algorithm and have it selectable at boot
time? Sure, its more work to get a complete product together, but in the end
it makes a product that would have a really nice advantage over most of
what's out there.

MDC
--
Marin David Condic
Senior Software Engineer
Pace Micro Technology Americas    www.pacemicro.com
Enabling the digital revolution
e-Mail:    marin.condic@pacemicro.com
Web:      http://www.mcondic.com/


"Ted Dennison" <dennison@telepath.com> wrote in message
news:eGN_6.942$Kf3.12916@www.newsranger.com...
>
> The one from my school days explicitly disclaims any intention of covering
> RTOS's up front. Their rationale was that general purpose OS's and RTOS's
have
> design goals that are fundamentally incompatable. For example, an RTOS
usually
> can't allow time-slicing between equal priority tasks, while
general-purpose
> user OS's need to in order to achieve fairness in scheduling. Also, RTOS
innards
> must be carefully crafted to provide a short and determinstic response
time.
> However, that typically means fixed-length data structures, and thus
limits on
> resources that a multitasking user OS might find annoyingly constraining.
>
> I'm curious if this is the unversal perception among OS developers today.
>
> ---
> T.E.D.    homepage   - http://www.telepath.com/dennison/Ted/TED.html
>           home email - mailto:dennison@telepath.com