Scott Reynolds wrote:
>On Tue, 6 Feb 1996, Bernard Gardner wrote:
>> I've just seen an Apple Press release, indicating that Linux is being ported
>> to the power mac platform. The port is being done by OSF, and will run onach
>> the Mach microkernel.
>
>Well, it seems to me that this is something of a contradiction... not to 
>say that your information isn't correct, but isn't this really a Mach 
>port with a Linux server on top?

In fact, we've ported the Mach kernel to the PowerMac and we've ported
Linux to Mach as an architecture-neutral pseudo machine. There are
very few changes to the generic Linux sources required to do this, and
it means that it is simple to keep up with Linux releases (in fact, we
expect to have our changes merged in to Linus's distribution). Linux
now becomes a pageable task just like all the others.

The machine-dependent parts of the Linux server (syscall and exception
handling, signals and fork) took two weeks to port from Intel to
PowerPC.  The performance we currently get is at 93% of native Linux,
having only started on performance measurements a fortnight ago. We
expect to catch up with native Linux with a bit of work, we already
know where we can improve and how to do it.

A major advantage of using a microkernel is that once you've ported
the microkernel, it's *extremely* easy to port any servers for that
microkernel to the new platform. Another advantage is the scope for
taking advantage of the features offered by the microkernel (SMP
support, IPC/RPC, hard real-time facilities, amongst others). And it's
fun!

> >If that is the case, it should be relatively easy to take this work
> and put a BSD server on top of Mach, or better, a native BSD port.

Server makes sense to me, but then again, that's why I work where I
do. Why go about reimplementing the wheel for each O/S? Especially
since there's a whole range of macs to support out there and it's not
just 'one' port that you have to do - Mach'll take care of that bit
for you, together with providing you with the free source code to look
at/hack/add to and improve.

     [ Nick ]
 -
Nick Stephen		     Web:   http://www.gr.osf.org/~stephen
OSF Research Institute	     Email: stephen@gr.osf.org
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