[Techtalk] Theory vs. practice

Mary E. Mulderrig mulderig at speakeasy.org
Tue Jan 15 20:00:53 EST 2002

Would a priority queue help?


-----Original Message-----
From: techtalk-admin at linuxchix.org
[mailto:techtalk-admin at linuxchix.org]On Behalf Of Mary Gardiner
Sent: Tuesday, January 15, 2002 6:57 PM
To: techtalk at linuxchix.org
Subject: Re: [Techtalk] Theory vs. practice

On Tue, Jan 15, 2002 at 06:35:22PM -0500, Raven, corporate courtesan
> Quoth Val Henson (Tue, Jan 15, 2002 at 03:29:14PM -0700):
> > What's wrong with this picture?  A Platinum account holder just
> > spent 3 hours waiting for a Gold account holder, when theoretically,
> > the Platinum holder should have had first priority.
> Okay, I can see that that's bad.  Is there a way to quickly check
> which processes are freeing up resources rather than requesting them,
> and then assign a higher priority to those?  Something to the effect
> of "need $100, who's releasing $100?  You?  Up front!".  You could
> even do some sort of secondary categorization, such that if you had a
> Platinum account needing $100, and you had a Gold account waiting to
> deposit $100 and a Silver account waiting to deposit $100, that the
> Gold account would get priority over the silver even under the new
> "who's got $100" system.

Another problem I think that needs to be taken into account is that of
the actual teller being a process. So when, on a single CPU machine, the
teller wants to call out "Hey you, got a fast transaction? Just a cash
deposit in notes?" everything else has to stop.

And in context switched systems, the teller process needs to be switched
into memory - the teller's stack (variables) need to go back into place,
and the platinum or gold process has to go out. And even the thing doing
the switching is of course a process, although it is a kernel process...

So the teller and the bank need to have priorities too...


Mary Gardiner
<mary at puzzling.org>
Techtalk mailing list
Techtalk at linuxchix.org

More information about the Techtalk mailing list