Re: How are CPU Speed and Overall CPW Related? -- MIDRANGE-L

Nathan,

As everyone has been trying to tell you, you are comparing apples to
oranges by this measure.

It does bring up the point that no single machine is best suited to
solve all problems.

It wouldn't take much to bring your 100mhz PC to it's knees with some
other task running at the same time.  The AS/400 is not intended to be a
single function machine, so it is not optimized for those types of
functions.  And, yes, it will measure poorly when tested for something
it was not designed for.  As any machine would test poorly for something
it was not designed for.

I'm not sure what you are trying to get at, but you must face that
reality that the AS/400 is -not- the best machine at all things, But, it
is the best machine when a single machine has to do all things all at
once.

Although I liked the motorcycle vs bus example, I'll give you a
different one that actually relates to computers and the AS/400 in
particular.  This has to do with the response degradation curve.  That
is, under other systems, there is a direct, linear curve that
corresponds with the number of users and their response time.  The more
users, the slower the response time.

IBM created an I/O subsystem that flattened that curve.  A single user
was faster on the other system when compared to the AS/400, but 20+
users were slower.  (The same was true in token ring vs ethernet)  Now
why would IBM do this?  Well, from what I've read, IBM spends a whole
bunch of money on researching things like psychological factors in user
satisfaction.  What they found was that any given user was happier (more
satisfied) with a system that provided a consistent response time than a
system that went from fast, to slow, then back to fast again throughout
the work day.  So if you get .5 sec response time as a single user, you
will still get .5 sec response time with 20 or 100 or 10,000 users. 
(provided that you have the right model for the workload)

I guess the point that I'm getting to is that the AS/400 never was, and
never will be, optimized for a single user.  It is designed to be a
multi user, multi tasking, consistent response time, back room, boring
fixture.

"Nathan M. Andelin" wrote:
> 
> I have a 6 1/2 year old IBM PC.  It has a 100 Mhz Pentium CPU.  I tested the
> Foxpro code on that old system, and it still beat my RPG string handling
> program.
> 
> I really believe the RPG code to be more efficient.  The difference is in
> the computer hardware.  Why does an old 100 Mhz Pentium beat a 200 Mhz
> Northstar?
> 
> Nathan.
>
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