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From: jxh@cup.portal.com (Jim - Hickstein)
Newsgroups: comp.sys.ibm.pc,comp.sys.amiga
Subject: Re: OS/2 vs AmigaDOS
Message-ID: <18779@cup.portal.com>
Date: 25 May 89 06:48:25 GMT
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Ahem.  I have been using OS/2 for some months, now, dabbling with PM until
I get the go-ahead to actually write our application, and I have these
observations about the discussion in hand:

1. OS/2 threads (and perhaps those elsewhere) are distinct from processes
in that processes own resources, notably segment descriptors, while a thread
is simply the unit of scheduler activity.  The result is that threads within
a given process must be mutually trustworthy, that is they must not stumble
and expect that the operating system will protect the other threads from their
mistakes.  For that reason, I have sympathy with alex@mks (I have your beta
version: good work!) who laments that fork() does not quite exist for
OS/2 processes.  In keeping with the kitchen-sink philosophy that seems to
prevail, perhaps fork() could be added to all the other primitives already
there.  To echo a previous sentiment: I like having options.

1A.  However, I would point out that, under OS/2, fork() cannot be made quite
as inexpensive as Kaare Christian rightly pointed out, because most of what
is copied for the child is, typically, a single code and single data segment;
lacking pages (so far: when did you guys say OS/3 was due?) it must copy
an ENTIRE segment for each (could be quite small, but the linker tries hard
to fill them up to conserve selectors). This is probably going to be at
least 100KB copy on fork().  Given the sizes of things generally under OS/2,
this doesn't seem large, but for such an important function as process creation,
it adds up.

2. Whatever other things came before (Amiga, OS9, you name it), I like OS/2,
chiefly because it is AN OPERATING SYSTEM.  I have been swearing at MS-DOS
for TEN years (remember SCP 86-DOS from Seattle Computer Products? I had
serial number 12.  Pay attention!) having come from a mainframe background
before that.  Indeed, I have been swearing at 8-bit microcomputers for longer
than that, wishing someone would sell a Cyber on a chip so we could get some
work done.  Now, with the advent of devices that might give a Cyber 74 a run
for its money (25 YEARS LATER!), I'm stuck with a PC on my desk which (like
all its bretheren) is I/O choked.  *sigh*  I guess there's no pleasing some
people.  Anyway.  At least the software is beginning to catch up with ideas 
that have been around for DECADES.  Given that OS/2 is hot off the press, I
expect that it will mature rapidly and nicely.  It is important for Microsoft
to keep an eye on this forum, among others, but we should be guiding its
development, not throwing rocks at the developers.

-Jim Hickstein
OS/2 PMSDK Masochists Group :-)
VSAT Systems, Inc.
San Jose, CA
jxh@cup.portal.com
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