Minutes of the meeting held on 23/ 7/1968 at State House, London

• Present
  • Lord Halsbury (Chair)
  • Dr R A Buckingham
  • Professor T Kilburn
  • Dr T G Pickavance
  • Mr L F Rutterford
  • Dr J Howlett
  • Mr C Jolliffe
  • Dr J H Price
  • Mr R St J Walker
  • C M Wilson ICL
  • J C Deas ICL
• Apologies
  • Dr A H Halsey
  • Professor E S Page
  • Professor R E Peierls
  • Professor M V Wilkes

1 Congratulations

Before starting the formal business of the meeting, the Committee recorded its very great pleasure in the award of a Knighthood to Sir Rudolf Peirls.

2 Purchase of New Computer

1. The meeting was called to discuss a single item, the purchase of a new computer for the Atlas Laboratory. at the previous meeting held on 26th April 1968 the Committee had discussed the proposal for an ICT P.51 system described in ACC/68/4, but had not been able to reach a decision because of lack of information from ICT (Minute 6 of the meeting refers). Since that time the merger of ICT and English Electric Computers had been effected and the new company ICL formed by the merger had settled its production policy for the 1900 and System 4 ranges and given the Committee (in confidence for the time being) a technical specification for the P.51 system. the offer described in ACC/68/4 was now confirmed in every respect - performance, price and delivery - and could therefore be taken as a firm basis for discussion. The fast processor would in future be called the 1908A
2. The position after the 26th April meeting had been reported to the UST Board at its meeting on 25th June 1968. The Board (Minute 207) agreed to support the proposal if the Atlas Committee, after being given the information it needed, recommended it to do so. The Board appointed a sub-committee (Sir Ewart Jones, Lord Halsbury, Professor Ford, Dr Gavin) to act on its behalf on receiving the Atlas Committee's decision.
3. The meeting was conducted on the basis of ACC/68/4, supplemented by the technical document from ICL, a copy of which had been sent to each member. At the suggestion of the Chairman, ICL was invited to send representatives to answer questions on the proposed system. Dr C M Wilson and Mr J C Deas attended in this capacity.
4. Questions to the ICL representatives, and discussions arising from the replies, took up the greater part of the meeting. The main points made were as follows:
   1. ICL were firmly convinced that the whole project was sound and that the delivery dates they had offered were realistic. They were confident of getting adequate supplies of the advanced components which they needed - in particular the 330ns store, the 50ns and 100ns buffer stores, the mass core store and the 1ns integrated circuits. They were expecting to sell some 30-40 1906A installations, but knew that several potential customers would not buy the machine unless they knew that the 1908A was to be produced.
   2. The twin-processor system could be either 1906A + 1908A (as proposed) or 1908A + 1908A. Provisional twin-system software would be supplied initially (i.e. in mid-1972 for the Chilton installation) which would allow, for example, sharing of the file store by the two processors, but a fully integrated operating system would not be available until mid-1973.
   3. The first prototype 1906A had power on now and should be running as a complete machine, with peripherals, by January 1969. the second prototype, which would have the proper production platters from their automated plant, should be at the same stage of development as the first by march 1969. Software would be developed on these machines and on a specially-built 1905E with paged store, due to be delivered to Putney in February 1969. Present production plans were:
      • First production 1906A in June 1970, thereafter approximately one a month with plans for ten in 1971.
      • First production 1908A in April 1972, with total of four in 1972 and six in 1973.
   4. ICL had made a detailed comparative study of the architectures of the 1900 and System 4 series and had concluded that the former, which was much simpler, was the better basis for the powerful machine. To provide the same computing power with the System 4 design (which is the same as the IBM System 360) would have to involve more complex design, cost more and take longer.
   5. Asked about ICL's plans for the future, Dr Wilson said that they were expecting to introduce a new product set about 1975 or 1976, but much study was needed before its form could be decided. they were very conscious of the need to make changeover easy both from 1900 and System 4 machines, so that the very big investment in programs, both of the Company and by users, should not be wasted. He felt that this need to preserve the value of the investment would ensure a long life for all the large families of computers, including the ICL 1900 series and especially, because of the numbers involved, the IBM 360. His view was that there was little risk of rapid obsolescence of these machines.
   6. ICL recognised that there were deficiencies in some of the basic software of the 1900, in particular in the operating systems and the Fortran compilers; they were working on these and were confident of making considerable improvements. They did not agree with the view that the short character-length (6 bits) and small number (3) of index registers of the 1900 were a serious drawback to this series.
5. Professor Page had re-emphasised in his letter the suggestion he had made at the previous meeting: namely, that the Atlas Laboratory should install the 1906A and peripherals as proposed in ACC/68/4, and the mass store, as soon as possible, and rent from ICL a second 1906A until the 1908A was available. The Laboratory could then start to develop the twin-system operating system, preferably in collaboration with ICL, with the expectation of having this working by the time the new processor was delivered. This would also provide more processing power in the years 1970-72, when there was virtually certain to be a serious shortage throughout the universities. The ICL representatives said this seemed feasible but needed study; the Company was not proposing, in general, to rent 1906A systems. Mr Walker said there were financial problems, especially as it was now certain that the Council's grant would be cut. Dr Howlett undertook to discuss all aspects of the suggestion with ICL and Finance Branch.
6. After the ICL representatives had left the meeting, the Committee briefly reviewed the arguments - discussed in the preceding three meetings - in favour of a new machine at Chilton, and agreed that these were still valid; and agreed that ICL had now removed the doubts and uncertainties about the new project. They recorded their decision to recommend to the UST Board that the proposal, as already put to the Board provisionally, should be supported. Details of the make-up and prices of the proposed system are given as Appendix I to these minutes.

3 Appendix I: Prices of New System

Note 1: This refers to the switch and connections which link the two processors and allow the peripherals to be assigned to the processor in any way.