Chapter 5 1961-1975

The “Go-Go” Years &

System/360

IBM & The Others 1963- $1.2 billion (70%) 1965- $ 3 billion 1970- $ 7 billion Sperry – Rand (UNIVAC)- mid 1960’s - $

145 million CDC (mini), Honeywell, Philco, RCA, GE,

Burroughs, NCR- mainframe builders Snow White & 7 Dwarfs 1970’s BUNCH Stable until 1980’s personal computers

System/ 360 Announced April 1964 - “full-circle” of

customers – business & scientific Line, 6 models-sw upward compatible

25:1 performance range Plus 150 different items

Fortune Magazine: “You bet your company”

1100 orders in 1st month In 5 months, 2200 orders

Success was a “threat” Could not meet demand

IBM 360 - 1964

SPREAD - IBM committeeMet daily 2 months in 1961Review past & decide the future

Couldn’t continue to “upgrade” Needed a “unified product line”“Scalability”

Fred Brooks, Gene Amdahl“can’t be done”

Scalability 1951- Maurice Wilkes, Manchester

University “best way to build an automatic

calculating machine” was to build its control section as a little stored – program computer of its own

“Micro- programmer”; microcode Page 148

Scalability – Adopted for 360

Allowed common instruction set Specialization & optimization for

models Via microprogramming

Read only memory Compatibility with earlier IBM’s

Emulation Separated design process from

control logic

Compatibility Microprogramming facilitated Emulated earlier IBM models

7070 and 1401 Up to ½ of 360 time was emulating

Due to new HW, new machines “emulated” old ones up to 10 times faster

Honeywell H-2000 + liberator emulated 1401 – sold well!

Software - more permanent than hardware 1401 programs run today

Part of Y2K problem

360 Features 16 General purpose registers 32-bit words

Finally a power of 2!! 8-bit character code – byte (1956)

EBCDIC – true 8 character code Originally also included ASCII; dropped

Channels retained Peripherals PDP-8: real-time, labs, etc.

Side Note on ASCII1963- American National

Standards InstituteAdopted 7 bit ASC II, not 88 holes across paper tape would

weaken it too muchBecame established in mini’s

Time-sharing & 360 System/360=> 360 degrees=> “full

circle of customers” Did not address time-sharing No dynamic addressing

@ this time – interactive=> one user Batch jobs “shared” time – one job in

memory John McCarthy- MIT

Each user has illusion that complete machine & SW at her disposal

THE Time-Sharing Problem

Page 155 Lots of wasted cycles

between key strokes – instructions

No efficient method for program swapping & keeping track

Time Sharing - Mid-1960’s

MIT, IBM 7090 CTSS - Compatible time sharing system Supported just a few users

Defense Dept.- Project MAC Chose G.E. over 360 GE became leader in time-sharing

IBM crisis Problems with program swapping Had not thought it would be important Model 67: TSS failure

Anti-trust lawsuit – premature announcement

Time-sharing

Progress was made – but still slow to develop workable

time-sharing -- Demonstrated feasibility but not practicality

Much turmoil in industry GE sold to Honeywell Movement to PDP machines - UNIX IBM threatened by success

IBM Stretch

IBM System /3IBM 360 could not

compete in mini market

System /3 Incompatible with 360$1000 monthSmall 96 column punch cardEventually floppy disk

The 1960’s Leasing companies

IBM too expensive Development costs Others 20% less Could withhold technology

1970 - IBM 370 360 compat. w/ time-share,

integrated circuits (cpu,mm) 1978 - IBM 4300

360 compat, low cost 1978 – AS/400 Leasing companies in debt

due to upgrades

“Go-GO” years Stocks soared

for all electronics companies

Compatible MainframesPossible attacks on 360

line Information to numerous companies

1964 - CDC 6600 (above) Designer Seymour Cray Supercomputer – Fastest performance

Small sales ~ but impressive ~ serious customers

Sued IBM – announcement 360 model 91

Compatible Mainframes

1964 – RCA – Spectra 70 SeriesRan 360 Software (1st clone)40% less $ than IBM, 4 modelsUsed true integrated circuitsLost in 1970 ~ 370 announced (IC’s)Out of computer business

Another round of buy-outs

Plug Compatible Manufacturers (PCM)

Others targeted 1 part ~IBM systemTape drive, memory, CPUThese companies soared IBM price cuts, packaging

1969-75, 10+ lawsuitsGene Amdahl-1970

Left IBM, own co.Fujitsu, other Japan

Software Houses Industry needed SW!!! Companies providing software

Automatic Data Processing (ADP)~payroll Computer Sciences Corp. (CSC) American Management Systems

IBM Included programming, service in price 1968 agreed to separate (lawsuit) For 360 success need for others to

provide SW & service Bad IBM SW – OS 360, PL/1

Software Houses – cont’d

1962 - EDS – H. Ross Perot Left IBM over “leasing of time” Success with government contracts Based in Dallas

Ramo-Wooldridge TRW Manufacturing + SW + Service Military, space, etc. Later into business apps.

IBM vs. Justice DepartmentFiled January 1969Lasted 12 yearsSell computers, UnbundleDropped January 1982PC Effect? Why didn’t IBM pursue PC

market?

The “BUNCH” Unisys = Burroughs + Univac (86) AT&T hostile take-over of NCR (91) Honeywell

Partnered with NEC, Bull & Olivetti Phased out of computing

CDC – up & down – suffered Cray

departure

PLATO (p. 175) Education system failureAhead of it’s time

Chapter 5 – 1961-1975

The “Go-Go” Years &

System/360