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From: dan@ccnysci.UUCP (Dan Schlitt)
Newsgroups: news.sysadmin,comp.misc
Subject: Re: computer charge back
Message-ID: <1674@ccnysci.UUCP>
Date: 21 Apr 89 14:01:28 GMT
References: <885@hawkmoon.MN.ORG> <1989Apr16.020150.1083@utzoo.uucp> <16570@oberon.USC.EDU> <1989Apr18.004953.10427@utzoo.uucp>
Reply-To: dan@ccnysci.UUCP (Dan Schlitt)
Organization: City College Of New York
Lines: 66

In article <1989Apr18.004953.10427@utzoo.uucp> henry@utzoo.uucp (Henry Spencer) writes:
>In article <16570@oberon.USC.EDU> blarson@skat.usc.edu (Bob Larson) writes:
>>Not all users are as unaware of resorce usage as Henry seems to assume,
>
>Uh, it's not an assumption, it's an observation.  Utzoo is a "production"
>system serving a mostly-computer-naive population.  Please remember one
>important distinction:  Computer Science types, even undergrads, understand
>much more about what's going on than other users.  A shop full of CS types
>is atypical and behaves atypically.
>
All the same old arguments.  YUK!!  We are being afflicted by creeping
IBMism.  This subject of charging for computer resources is a confused
swamp.  A lot of the cause is that most people learned about the
subject because they used "large" batch oriented computer systems that
used JCL.  I thought I got away from it when I changed to unix.  Alas,
I was wrong.  Bad ideas have a way of persisting.

The first thing that you must decide is what you want to accomplish by
this accounting.  I thought that the original question was directed
toward recovery of costs.  That is a reasonable goal.

A second kind of thing that you may want to do with charges is to
allocate (scarce) resources.  This is also a reasonable goal.
The result is usually the university computer center funny money
system.  However, this goal is different from the first and will 
frequently conflict with it.

While both of these kinds of charging will alter user behavior to some
extent, the second has that as a primary goal.  This discussion has
drifted off in this direction as the quoted material shows.  My
experience over yea many years is that it doesn't work well.  There
are other, better ways to do the resource allocation.  (They don't
work all that well either if what you want is modified user behavior.)

I suggest that the important thing to consider in designing the
charging system is that it not inhibit the productive use of the
computer system.  When you start talking about charging for something
you induce an accountant mentality which completely loses sight of
this.

If what you want to do is recover costs then there have been some good
suggestions in previous articles.  Among the important ideas -- CPU
cycles are a parishable commodity so the CPU is really a capital cost
to be shared -- consumables like paper should be paid for on the basis
of actual use.  For interactive use connect time may be a very
reasonable way to measure relative use of a shared CPU.

If resource allocation is your goal, user education is your only real
tool.  It is as effective as education of any kind :-).  It is my
opinion that the BSD disk quota and resource limit facilities are
about as good as anything for protecting against the consequences of
over use.

You can force students to endure all sorts of nonsense (although you
shouldn't), but in other parts of the world there are real costs to be
taken into account which are ignored in the computer charging stuff.
For the computer user all time is real time.  If your charging methods
reduce the productivity of your programming staff or discourage the
computer shy from taking advantage of computer facilities then you
have failed to include an important cost.

-- 
Dan Schlitt                        Manager, Science Division Computer Facility
dan@ccnysci                        City College of New York
dan@ccnysci.bitnet                 New York, NY 10031
                                   (212)690-6868