20 Feb
2018
20 Feb
'18
10:33 p.m.
On 2/20/18, Donald ODona <mutiny.mutiny(a)india.com> wrote:
since '86 he was working on an operating system,
named Mica, which failed.
At 19 Feb 2018 18:13:59 +0000 (+00:00) from Paul Winalski
<paul.winalski(a)gmail.com>:
> Dave Cutler was in the VMS group only for VMS version 1. He rarely
> stayed on around for version 2 of anything. Hustvedt's and Lipman's
> contributions for VMS were more extensive and longer-lasting than
> Cutler's.
Cutler had already left the VMS OS group by the time I joined DEC in
February of 1980. After VMS he led the team developing PL/I and C
compilers for VMS. These shared a common back end called the VAX Code
Generator (VCG). The other VMS compilers at the time (Fortran,
Pascal, Cobol) had their own separate optimizers and code generators.
The VAX Ada compiler would also use VCG.
When version 1 of VAX PL/i and VAX C shipped, Cutler worked on
subsetting the VAX architecture so that a single chip implementation
could be done, and led the team that produced the MicroVAX I. The
MicroVAX architecture emulated expensive instructions such as packed
decimal. All of the later, single-chip VAXes used this architecture.
When the MicroVAX I shipped, Cutler devised a microkernel-based
real-time operating system for the VAX called VAXeln.
After VAXeln, Cutler led the team developing a RISC architecture
follow-on to the VAX called PRISM, and an operating system for it
called Mica. Mica had a VAXeln-like microkernel, and the plan was to
layer personality modules on top of that to implement VMS and
Unix-style ABIs and system calls.
Alpha was chosen instead of PRISM as the VAX successor, and that is
when Cutler left DEC for Microsoft. Windows NT has a lot of design
concepts and details previously seen in PRISM and VMS.
-Paul W.