November 18, 1974

Dr. Harry E. Pople

Machine Intelligence Systems Laboratory
University of Pittsburgh

401 Bruce Hall

Pittaburgh, Pennsylvania 16260

Dear Dr. Pople,

Dr. Carl Brewer referred your letter of October 28th to the meeting
of the BSUMEX-AIM Advisory Committee that was held here on November 14th.
I have been instructed to reply in the following vein.

We are of course eager to provide every reasonable support that we
ean for your project but must of course comply with the restraints of
limited resources that can be anticipated as the national program develops.
You should have the following information for planning purposes. We will
do whatever we can to relax these constraints and to facilitate the optimum
utilization of the resource in ways that may best compromise your requirements
and those of other users.

Dr. Bobrow advises us that the modifications of INTERLISP mentioned in
your letter have been or shortly will be implemented. You may wish to contact
him directly about any problems that may arise in that area.

We think we can assure you a facility that will permit you to maintain
the level of activity you requested for the initial period with the following
provisos: (1) that during heavily loaded periods you will not ordinarily
have more than one user exeeré&tigga major LISP job. Of course, there may well
be additdonal ones doing editing and debugging that will not place quite so
heavy a demand.

(2) We can allocate 2,000 pages (1 million words) of disc space with a
probable availability of the remaining 2,000 pages requested but this is
still to be worked out.

(3) As to CPU utilization, you should plan for a possible constraint to
approximately 1/2 hour per day, during prime time, with a reasonable
possibility but no guarantee of expansion during lightly loaded or off~peak
periods.

(4) Terminal connect time is not at this time a constrained resource.

Qur advisory group believes from its own experience that on the SUMEX
machine 8 - 10 hours of connect time is unlikely to require more than the
1/2 hour of CPU indicated. We will be studying this situation and will be glad
to have the benefit of your own further experience in working out future
adjustments.
Dr. Harry E. Pople -2- 11/18/74

Your letter also refers to requirements for 1976 that could result
in a load of 4 - 5 hours of CPU time per day. Unless we can implement a
major augmentation of the system which may be possible in due course but
is unlikely by s0 near a time, I do not think it will be physically possible
to comply with a request of that magnitude. As your work approaches the
evaluation stage, we may have to reexamine the econgruency of the research
and development mission of SUMEX~AIM with the larger scale evaluation and
demonstration objectives indicated in your proposal. Believe me, we all
understand the difficulties of making these kinds of decisions and if
any of this appears to be negative, it is only in the smnse of trying to
meet a set of often contradictory or at least conflicting requirements.

As far as our accounting statistics tell, your current behavior on
SUMEX falls very comfortably within the indicated constraints and you perhaps
really need not concern yourself about a gradual build-up of activity, as
we will be implementing both policies and algorithms to try to soften the
harshness of the realities of scarce resources, (We have to be careful of
the psychological trap that may result from the fact that the system is
only just beginning to be implemented for national use).

We hope that it will be possible for you to pursue your principal research
aims despite these limitations and that we will continue in a cooperative mode
to find ways of solving the problems that beset ef1 of us.

I will be in touch with you later from time to time about other ways
in which we may be able to be of mutual help and certainly welcome you and
look forward to a fruitful association.

Please take advantage of the SNDMSG facility on SUMEX for communication,
or the mail or the phone or whatever best suits your convenience for staying
in close touch with us.

Sincerely yours,

Joshua Lederberg
Principal Investigator

JL/rr
Enclosures
ccs Dr. Carl R. Brewer
SUMEX~AIM Executive Committee