David Patterson Speech on RISC at Draper Prize
Furber, Hennessy, Paterson, Wilson won Prize for RISC in May this year.
Earlier this year four of the pioneers of ‘Reduced Instruction Set Computer’ processor designs were awarded the Charles Stark Draper Prize for engineering, for their work on RISC.
David Patterson : Pardee Professor of Computer Science, Emeritus at UC Berkeley
John Hennessy : Professor of Electrical Engineering and Computer Science at Stanford University
Sophie Wilson : Research Fellow at Broadcom, Cambridge UK
Steve Furber : ICL Professor of Computer Engineering in the Department of Computer Science at the University of Manchester
Of course Patterson and Hennessy are better known for their work on the ‘Berkeley RISC’ / ‘RISC-V’ and ‘MIPS’ processors respectively and Furber and Wilson for their work on the first ‘ARM’ processors.
The awards ceremony was in four parts: the usual introductions, a short film - seen on YouTube above, making the awards themselves and then a 10 minute speech from David Patterson. A link to the full video is here. Patterson’s speech begins at 20.30.
The speech is the reason for posting details of the event. It’s a summary of the history of RISC seen from the perspective of some of the pioneers. It’s well worth watching in full as it draws together some of the key themes of the early days of RISC. Here are a few short excerpts that give a flavour of the early thinking behind RISC.
Whilst high level languages were popular for many tasks, convectional wisdom was that compilers were too inefficient for some software, such as operating systems.
The success of the UNIX operating system at Bell Labs in the late 1970s written in a high level language changed people’s minds.
Hennessy and I thought it would be easier to build microprocessors that understood RISC vocabularies than CISC vocabularies and easier for compilers to generates RISC programs than CISC programs.
The question then was whether RISC or CISC was faster. While a program might have to read fewer instructions using CISC, since the instructions were more sophisticated, that might mean that the average instruction would take longer to read and execute than a RISC machine.
This seemingly clear engineering question was emotion packed in our computer design community, which we call computer architecture.
Whilst Berkeley and Stanford are rivals in the Bay Area, Hennessy and I both realised that we should join forces to argue for RISC.
Patterson then goes on to describe how the debate progressed and then how Arm in Cambridge in the UK picked up the challenge of proving an architecture for mobile and low power devices.
The talk thus draws together four separate themes from RISC’s successes in its early years: the increasing importance of compilers, ease of design, speed of execution and power consumption.
It’s an interesting talk and it’s great to see these pioneers being honoured. I have to say at this point that John Cocke and the team at IBM also deserve a mention for their work on RISC in the 1970s.
One interesting point: Patterson refers to Arm as the first commercially available RISC microprocessor which surprised me but, checking the dates, does seem to be true.
Do subscribe for more posts on the early days of RISC, coming in the near future.
Postscript
In the introduction video there is a graphic of assembly language scrolling down the screen. The assembly language is of course x86-64 which is definitely a CISC and not a RISC instruction set architecture!
Image Credits
David Paterson
By Peg Skorpinski - Subject of pictures emailed it upon request, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=3207893
John Hennessy
By Eric Chan - originally posted to Flickr as Provost John Etchemendy (However this picture shows President John L. Hennessy instead of Provost John Etchemendy), CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=6504543
Steve Furber
Peter Howkins, CC BY-SA 3.0 <https://creativecommons.org/licenses/by-sa/3.0>, via Wikimedia Commons
Sophie Wilson
By Chris Monk - https://www.flickr.com/photos/101251639@N02/9669448671, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=68622523