FYI: "FSF work on a GNU OS" posted to

Mariusz Stanczak Mariusz at
Sun May 12 15:49:08 AEST 1991

In article <75230 at brunix.UUCP>, cgy at (Curtis Yarvin) writes:
> In article <110 at> Mariusz at (Mariusz Stanczak) writes:
> >the differences between Mach kernel, and the future microkernel [I think in
> >CTR]) mentioned a 1000 line C code for the whole thing.
> Your decimals need some work.
> We have Mach 3.0 code here.  Note that this is NOT the version with BSD
> wedged into the kernel.

BTW, not intending to nit-pick, but maybe things could be wedged into
a kernel, but they are layered around a microkernel... one is rather
monolithic, the other modular.

> Kernel source alone is about 100,000 lines of code.  This does not include
> any of the machine-specific sections, which can be quite large; for example,
> the i386 machine-specific code is 40,000 lines.

I wonder... are we talking about the same thing?!  Mach MICROkernel, not
kernel.  Big difference (though, admitedly, I had no idea of the actual
size of the kernel) in fuctionality.  Mach kernel includes most of the
kernel of the *nix OS as we know it, microkernel isn't much more then
task/context switcher, and a process cop, with "everything" else modula-
rised over it.  Because of the modularity of all the functionality in Mach,
one can mix and match what is implemented.  A far cry from the monolith
bloat of the current kernels.  So what does the decimal-point-corrected
number of lines of source contain?

> The idea is about ten years old.

How long have you known about?  The idea yes, but the code has been
taken out of the labs barely four/five years ago, and even then it
contained enough of AT&T code not to be freely distributable.  The
Mach microkernel is, and it's been so for about a year (if that!).

> >and OSF's implementation (with all its resources, and commitment) is a
> >couple years away.
> A prerelease version of OSF/1 is running quite stably on a Decstation 3100
> here at Brown.  Note that OSF/1 is BSD wedged into the microkernel, not
> built around it.

Again, are we talking about the same thing... the current OSF/1 release
is build around the Mach KERNEL, with late 1992/early 1993 date for the
new version that WILL be built around the Mach MICROkernel.

> Vaporware is any software or hardware which has been announced but not yet
> completed.

Ours seem to be a difference of understanding... there's a distinction
you overlook, and that's between a preannounced PRODUCT, and an intent
to work on "some" (as in "any") software.  Do you see Intel's press 
announcment of a 100 MIPS CICS (some months back, and prompted be the
wave of RISC chip releases), and sombody's on the net word of intent
to work on some problem as the same? ... I hope not, and the usage of
the word "vaporware" has a rather more specific meaning to the former
of the two cases.

INET: Mariusz at
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UUCP: ..!uunet!zardoz!ttank!fbits!Mariusz

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