🚀 go-pugleaf

In article <19950904.1178078.10576@olympus.net>, dons@olympus.net (Don
Schmelling) wrote:

> Nevin ":-]" Liber (nevin@CS.Arizona.EDU) wrote:
> : In article <19950903.1175360.FCDB@olympus.net>, dons@olympus.net (Don
> : Schmelling) wrote:

> : > Nevin ":-]" Liber (nevin@CS.Arizona.EDU) wrote:
> : >I do not think of all
> : > end-users as dumb, just the ones that are.

> : It sure as heck sounds like you consider someone dumb if they don't agree
> : with your *opinion*.
> You just do not know me well enough to make an assertion such as this.

Oh?  Why is it that I'm not allowed to make a public opinion about you,
while you are allowed to have a public one about me, as evidenced by your
remark:

> I would expect someone with an email address that ends in .edu to
> be more sensible than this.

You ought to practice what you preach.  You certainly don't know me well
enough to make an assertion such as this.

> I had an end-user walk into a computer lab once and say,
> "How come the computer is not doing anything?"
> I said, "Well it has to be powered up first."
> I definately consider that a dumb end-user.

Again, in your *opinion*.  Paraphrasing *your own words* again, you don't
know that person well enough to make an assertion such as this.

In my opinion (and I get to have one, since I don't subscribe to your
theory that I am unqualified to comment, since that too is an assertion
presented without justification), that is a scared user, not a dumb user. 
And why shouldn't they be?  In their eyes, they could potentially be
destroying tens of thousands of dollars worth of equipment by touching
that machine.  Sure, you may claim to know better, but you certainly
weren't born with that knowledge.

> Would the same
> person consider asking why their car does not go anywhere if
> they had not put the key in the ignition and started the car?

Think back to the very first time you drove a car.  Weren't you just a
little apprehensive?  Were your parents irresponsible enough to just hand
you the keys that day hoping you'll figure it out on you own, or did they
train you/enroll you in a driver's education class for a few weeks/months
before they would let you risk their $10-50K car/$1-2K insurance rate/your
life?  Would you be willing to give the keys to your car to a 14 year old
kid who has never been behind the wheel of a car and let them go drive it
unsupervised?  If not, why not?  If so, put your car where your mouth is.

> : > So do you feel good about making up a number like 99%???
> : > Maybee 99% in your shop, but not worldwide.
> : 
> : Roughly speaking, 80-90% of the machines out there run DOS and Windows. 
> : Another 8-15% of them are Macintoshes running System 6 or 7.  None of
> : these have PMT yet (with the possible exception of Win95, depending on
> : whether or not you believe the hype).  Everything else is in the noise. 
> : What number do you come up with?  Maybe 5% of the machines out there have
> : a PMT OS, and that is being very, very generous.

> Have you included mainframes, mini computers, super computers, etc into
> your numbers?

Yup.  They are in the noise.  Plus, most of the industries are trying to
move away from them towards workstations because the maintenance costs are
too darn high.  Why are they so high?  Because the customer base is small.

> Also just because the majority of Personal Computers may run CMT
> does not mean that it is the best solution or that PMT is not
> indispensable.

Definition of indispensable:  essential, absolutely necessary (source: 
Webster's Ninth New Collegiate Dictionary).  Proof that PMT isn't
indispensable:  Assume PMT is indispensable.  We've been using personal
computers w/o PMT for nearly two decades.  The world hasn't ended, and we
still manage to get our jobs done.  PMT is neither essential nor necessary
to do computing.  Therefore, PMT is *not*indispensable.  Q.E.D.

As for your other point, sure there are specialized applications where PMT
is more desireable than CMT; I've never asserted otherwise.  You still
haven't even given one example where PMT is essential and absolutely
necessary (the definition of indispensable) and CMT and interrupts
absolutely, positively, would not work at all, let alone shown it for
every single computing application in existence, which was your original
assertion.  You seem to weaken it every time you post.

> CMT is not real multitasking, oh sure it may possibly multitask some
> applications, but it is not true multitasking.  To get true multitasking
> you need something like PMT.

Great.  You are just another person who gets all of his knowledge from
reading Usenet.  I suppose the religion you belong to is the one true
religion, too.  Can you cite even one source in a respected computer
journal / book that equates PMT with "true" multitasking?  I can cite you
sources on concurrent programming and operating systems (eg: Greg Andrews
book the Principles of Concurrent Programming) that talk about and use the
words cooperative multitasking, and they don't consider it to be "false"
or "fake" multitasking (nor do they mention DOS, Windows, or the
Macintosh).  I've been asking anyone on Usenet to cite a source for three
years now; no one has yet done it.

The NewsWatcher FAQ sums up this "true" multitasking crap very succinctly:

|    "True" is a term invented in the UNIX community, where it is defined to
| mean "like we do it on UNIX", as in "true multitasking", "true threading",
| and "the one and only true operating system".
| [...]
| Neither is "true" and neither is "false". Each has advantages and
| disadvantages.

I have a little secret for you:  the only difference between CMT and PMT
is how tasks get swapped; ie, the whether scheduling is under application
control or OS control.  Neither solution is perfect.  CMT apps have to
guess about what the rest of the system is doing; PMT OSes have to guess
about what all the apps are doing.  Some PMT schedulers, such as the one
in Copland, will be better at doing this, since the apps will cooperate by
telling the OS exactly what kind of task it is (UI, CPU-bound, etc.);
schedulers rarely get this right using heuristics alone (such as the Unix
scheduler).

> If you are running a large app in it takes
> more than I would say 1/2 sec of cpu time consecutively without passing
> the cpu to another task than you are not multitasking, you are
> running one task at a time.

If you only have one CPU you are only running one task at a time;
everything else is an illusion.  Since when did 1/2 a second become the
definition of what is/is not a multitasking system??

> Look at any of the major industries, banks, insurance, credit, and so forth.
> They keep their records on mainframes.

Of course they do.  You are only describing one type of computing; namely,
transaction-based fault-tolerant database processing.  Or course, this
example is irrelevant to all of the newsgroups that you posted your
message to.

> Do you know what kind of computer
> you are connecting to with a cash machine?

I would imagine it is a distributed fault-tolerant transaction-based
system; the kind that shows why it is hard to use PMT (you want
transactions to be atomic, fast as possible, and fault-tolerant; not easy
to get right).

> Do you have any idea of how many people use cash machines every day?

Nope.  Don't really care, either.  I use my car far, far more often than I
use a cash machine.  Is the OS in my car's computer PMT-based?  I don't
know, and again don't care.

> : That is a far weaker assertion than PMT being absolutely indispensable. 
> : Be self-consistent, please.
> Actually I am self-consistant, you just have a different definition
> of self-consistant.

How about someone who doesn't keep changing/weakening the premise w/o
acknowledgement every time someone else presents an argument that the
first someone cannot refute adequately?

> : > I guess you have no need for things like virus
> : > checkers, system clocks, and multiple apps?

> : I have all those on my Mac.  Amazing, isn't it?
> You may have them but they are not being run Preemtively, there is a BIG
> difference.

Here we go, another assertion without even a shred of evidence to support it.

Right now on my Mac, I am doing two concurrent file transfers via
Anarchie, printing a document, letting Eudora fetch my email, playing an
audio CD, surfing the Web with Netscape, and writing this message waiting
for some of the other stuff to finish (I need the files to do some work). 
Oh, and did I mention that I have a clock in the menubar merrily going
along, and it gets resynced via NTP every hour, just like those big PMT
Unix boxes?  I suppose I could go into my office and do this on a PMT
system with 3x as much horsepower as my Mac at about 5x the initial cost
(not counting the maintenance / lab staff), but the UI response is
pathetic compared to my Mac (and I'm the only one on the damn machine),
and the tools take much more work on my part to do the same job.

So, why don't you tell us *how* PMT is going to make our lives oh so much
better, instead of emptily asserting it without proof or justification
that it will.
-- 
        Nevin ":-)" Liber       nevin@CS.Arizona.EDU    (520) 293-2799
-- 
        Nevin ":-)" Liber       nevin@CS.Arizona.EDU    (520) 293-2799