From: David Leimbach <leimy2k@gmail.com>
To: Jack Johnson <knapjack@gmail.com>
Cc: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu>
Subject: Re: [9fans] Acme mailreader
Date: Fri, 17 Dec 2004 17:00:32 -0800 [thread overview]
Message-ID: <3e1162e604121717007ac5069a@mail.gmail.com> (raw)
In-Reply-To: <6e35c06204121715206e5ee022@mail.gmail.com>
On Fri, 17 Dec 2004 15:20:54 -0800, Jack Johnson <knapjack@gmail.com> wrote:
> On Fri, 17 Dec 2004 10:52:51 -0800, David Leimbach <leimy2k@gmail.com> wrote:
> > Mac OS X is not a microkernel architecture... but it does "have a
> > microkernel" :).
>
> I wonder how much of this is just NeXT heritage rather than
> purposefully to make the actual work of building/upgrading OS X any
> easier (or any other potentially valid reason)?
>
I suspect they liked some of the SMP capabilities Mach was endowed
with + the thread scheduling and VM. Even FreeBSD adopted the Mach VM
at one point [but not the rest of Mach]. Chances are they have TONS
of legacy code that requires a lot of work to get away from Mach.
NeXT ran with Mach 2.5 and XNU is a modified OSF Mach 3 if I recall correctly.
I don't think Mach is making anything easier for Apple except in
possibly some of their real-time scheduling of threads for multimedia
streaming and what-have-you. Other than that it's a pretty odd animal
at times.
It'd be interesting to see what would happen if they ever went with
something like L4 [a more current and more successful at being a
microkernel microkernel]. But L4 messaging is synchronous by
specification and I think Mach has a lot of asynchronous behavior that
might be hard to emulate initially.
It'd be a bit of work... However NetBSD does now have some level of
Darwin compatibility including a Mach layer so who knows!?!? It's
pretty danged offtopic for this list though :)
Dave
> -Jack
>
next prev parent reply other threads:[~2004-12-18 1:00 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-12-15 15:34 jim
2004-12-15 15:40 ` gdiaz
2004-12-15 15:47 ` jim
2004-12-15 15:50 ` Joseph Stewart
2004-12-15 15:57 ` jim
2004-12-15 16:10 ` Russ Cox
2004-12-15 15:58 ` Charles Forsyth
2004-12-15 16:04 ` jim
2004-12-15 16:24 ` C H Forsyth
2004-12-15 16:31 ` jim
2004-12-15 17:07 ` Russ Cox
2004-12-15 17:30 ` jim
2004-12-15 18:33 ` Russ Cox
2004-12-15 18:49 ` jim
2004-12-15 18:36 ` Axel Belinfante
2004-12-15 18:47 ` jim
2004-12-15 18:51 ` rog
2004-12-15 18:48 ` Skip Tavakkolian
2004-12-15 16:05 ` rog
2004-12-15 16:07 ` rog
2004-12-15 16:09 ` jim
2004-12-16 0:24 ` geoff
2004-12-16 4:12 ` Ronald G. Minnich
2004-12-16 4:51 ` geoff
2004-12-16 9:25 ` jim
2004-12-16 5:13 ` Skip Tavakkolian
2004-12-16 5:17 ` geoff
2004-12-16 5:20 ` boyd, rounin
2004-12-16 5:34 ` boyd, rounin
2004-12-16 5:29 ` Skip Tavakkolian
2004-12-16 15:54 ` Ronald G. Minnich
2004-12-16 17:52 ` Skip Tavakkolian
2004-12-16 18:13 ` Dave Eckhardt
2004-12-16 5:23 ` Andy Newman
2004-12-16 15:52 ` Ronald G. Minnich
2004-12-16 8:17 ` Martin C.Atkins
2004-12-16 9:35 ` jim
2004-12-16 15:19 ` rog
2004-12-16 15:26 ` jim
2004-12-16 9:30 ` jim
2004-12-16 15:08 ` David Leimbach
2004-12-16 23:22 ` geoff
2004-12-16 23:25 ` boyd, rounin
2004-12-16 23:38 ` Ronald G. Minnich
2004-12-17 1:31 ` Skip Tavakkolian
2004-12-17 15:50 ` Ronald G. Minnich
2004-12-17 4:55 ` [9fans] Acme mailreader - now: User mode filesystems in linux Martin C.Atkins
2004-12-17 9:54 ` Martin C.Atkins
2004-12-17 10:22 ` geoff
2004-12-17 10:45 ` Martin C.Atkins
2004-12-17 11:42 ` Andy Newman
2004-12-17 15:57 ` Ronald G. Minnich
2004-12-17 12:30 ` Latchesar Ionkov
2004-12-17 15:55 ` Ronald G. Minnich
2004-12-17 13:41 ` Derek Fawcus
2004-12-17 14:42 ` Karl Magdsick
2004-12-17 14:56 ` Russ Cox
2004-12-18 0:13 ` Tim Newsham
2004-12-18 0:13 ` boyd, rounin
2004-12-18 3:49 ` Ronald G. Minnich
2004-12-23 16:04 ` boyd, rounin
2004-12-17 15:44 ` Ronald G. Minnich
2004-12-18 12:35 ` Martin C.Atkins
2004-12-17 18:52 ` [9fans] Acme mailreader David Leimbach
2004-12-17 23:20 ` Jack Johnson
2004-12-18 1:00 ` David Leimbach [this message]
2004-12-15 16:09 ` Russ Cox
2004-12-15 16:16 ` jim
2004-12-15 16:22 ` boyd, rounin
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