Thanks to everyone who replied. Particularly Matt, that is a fantastic
analogy and exactly what I needed to present to the conference.
Cheers,
Matt.
----- Original Message -----
From: "Kevin Wells" <[EMAIL PROTECTED]>
To: "Multiple recipients of list delphi" <[EMAIL PROTECTED]>
Sent: Thursday, April 13, 2000 10:57 AM
Subject: Re: [DUG]: thread definition.
> Matt Powell wrote:
>
> > "Over here, we have a man. The man is ostensibly sitting on the couch
> > watching rugby and drinking beer, but notice that he can't do both at
the
> > same time. When he's drinking his beer, he will often miss an important
> > tackle or a particularly brilliant pass, and when the rugby gets really
> > exciting, his beer will remain untouched for seconds at a time. The man
is a
> > SINGLE-TASKING PROCESS.
> >
> > "Over *here*, we have a woman. Notice how the woman is able to do more
than
> > one thing at once. For example, she can be doing the ironing, planning a
> > complex meal and sorting out the social lives of her three children, all
at
> > the same time. The woman is a MULTI-TASKING PROCESS.
>
> Actually I think the man is multi-tasking, and the woman is
multi-processing.
>
> SHE is doing TWO THINGS AT THE SAME TIME. For the sake of the analogy you
could
> think of it as her left brain performing one task and her right brain
doing
> another task. So she has two processors.
>
> HE is repeatedly doing a number of tasks, but he is only ever performing
ONE
> TASK AT A TIME. His brain only ever performs one task at a time, but he
divides
> his time between tasks. So he has one processor that performs a number of
tasks
> in rapid succession. If the alternation between tasks is fast enough it
looks
> like he is doing two things at the same time.
>
> I like the analogy though. It might get a laugh. Unfortunately it does not
help
> to explain problems with resources that are shared by different threads.
>
> Kevin Wells
>
> P.S. There was a series of articles about multi-threading by Alan Holub in
> JavaWorld September 1999 (http://www.javaworld.com). He had a nice analogy
for
> mutexes:
>
> "The best analogy I've heard for a monitor is an airplane bathroom. Only
one
> person can be in the bathroom at a time (we hope). Everybody else is
queued up
> in a rather narrow aisle waiting to use it. As long as the door is locked,
the
> bathroom is inaccessible. Given these terms, in our analogy the object is
the
> airplane, the bathroom is the monitor (assuming there's only one
bathroom), and
> the lock on the door is the mutex."
>
> This leads to amusing examples of what happens if shared resources are not
> protected correctly.
>
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