Gene Amdahl – A Personal Tribute

By John L. Gustafson

November 19, 2015

Amidst all the other awful news of last week, the fact that we lost an amazing and wonderful man might have gotten pushed off the front page: Gene Amdahl passed away on November 10, at age 92. We have lost one of the greatest computer architects of all time; in fact, it was his design of the IBM System/360 in the 1960s that led to the first use of the word “architecture” to describe computer design.

The New York Times has a well-written obituary about the man (http://www.nytimes.com/2015/11/13/technology/gene-amdahl-pioneer-of-mainframe-computing-dies-at-92.html). I got to know Gene personally a few years after I published discussions of his eponymous law, and I would like to share with HPCwire readers some things about him that are not widely known or mentioned in his obituaries.

When IBM bet on Gene Amdahl’s ideas, it was perhaps the biggest business gamble of all time. They were literally betting the company on a major switch from their older 36-bit designs to a scalable 32-bit design. IBM won the bet, becoming by far the dominant player in the computer industry for decades, and to this day IBM sells computers that contain Amdahl’s instruction set and design ideas. Who else can claim to have designed an instruction set that has lasted over fifty years? And it wasn’t as if he had everyone’s full support at IBM; he had to fight for it. The company politics were quite intense and, as is typical, not everyone was on board with the high-risk change Gene was spearheading. Though he had been an academic, he proved quite talented at navigating company politics and getting IBM aligned to the massive effort.

It is one thing to be so inventive that you can create a mainframe design like the System/360 and its successor, the System/370; Amdahl had to invent it twice, two completely different ways! When he left IBM to found his own company to build rival computers (Amdahl Corporation), he found himself competing with his own patents. The royalties to IBM would have prevented his business from competing successfully, so he started with a clean sheet of paper and created all-new approaches that did not step on any of his early intellectual property, and were both faster and less expensive. That made Amdahl Corporation one of the few companies building computers with IBM-compatible instruction sets that made a successful business at it.

I once asked Gene why it was that his System/360 design did not support parallel computing, as did some of the Burroughs machines from the same era. He replied that he couldn’t figure out what the instructions would be for a parallel computer. It was not, as some might think, because he was opposed to the idea of parallel computing. This may be one of the major myths about Gene Amdahl: that he was fundamentally against parallel processing. He was chagrined that his famous 1967 debate with Daniel Slotnick at an AFIPS conference led people to think this about him.

I wish I could have seen that historic debate in person. The Single-Instruction Multiple Data (SIMD) ILLIAC IV was to have 256 processors when finished, though even the 64-processor version was a breathtakingly daring parallel design when the first pass was completed in 1966. Amdahl had recently introduced his single-CPU time-shared mainframe, so the stage was set. Amdahl estimated that the operating system of a SIMD computer like the ILLIAC IV would take about 25 to 45 percent of the processor cycles, based on his experience with the operating system of the System/360. In his overhead slides, he presented the standard engineering formula for applying two speeds to a fixed-size process, and argued that the ILLIAC IV would only achieve two-fold to four-fold speedup despite having 64 processors. The impact of the argument was huge. Willis Ware referenced it in a RAND report three years later, including the algebraic formula from Gene’s presentation and calling it “Amdahl’s law,” and the name stuck.

Gene told me he never intended that his argument would be applied to distributed memory systems with separate instruction streams, in which he became a believer and supporter in his later years. He and I served on the technical advisory board of Massively Parallel Technologies, and he could not have been a more enthusiastic proponent of the modern approach to massive parallelism.

Many computer architecture books and articles also point to Amdahl’s “guideline” that a well-balanced computer should have “a megaword per megaflop” or similar variants. I tried for years to track down the original source of this guideline, and could not find it anywhere. Then I realized I could simply ask him, since we were about to have lunch together. His answer surprised me: “I never said that.” Nor did he believe it was a good guideline! I suppose one of the hazards of being an industry icon is false attribution. It was a relief, since in the petaflop to exaflop era, we are certainly drifting quite far from that ratio.

I’m at the SC15 conference in Austin as I write this, looking over what seems like endless acres of exhibit hall displays. I believe every one of the companies on the trade show floor owes some or most of their existence to the foundation Gene Amdahl built for them, decades ago. He was THE original Computer Architect, and I will miss him as both as an amazing mentor and as a friend.

 

(Image Source: Computer History Museum)

Subscribe to HPCwire's Weekly Update!

Be the most informed person in the room! Stay ahead of the tech trends with industy updates delivered to you every week!

IBM Unveils Latest Achievements in AI Hardware

December 13, 2019

“The increased capabilities of contemporary AI models provide unprecedented recognition accuracy, but often at the expense of larger computational and energetic effort,” IBM Research wrote in a blog post. “Therefor Read more…

By Oliver Peckham

Focused on ‘Silicon TAM,’ Intel Puts Gary Patton, Former GlobalFoundries CTO, in Charge of Design Enablement

December 12, 2019

Change within Intel’s upper management – and to its company mission – has continued as a published report has disclosed that chip technology heavyweight Gary Patton, GlobalFoundries’ CTO and R&D SVP as well a Read more…

By Doug Black

Quantum Bits: Rigetti Debuts New Gates, D-Wave Cuts NEC Deal, AWS Jumps into the Quantum Pool

December 12, 2019

There’s been flurry of significant news in the quantum computing world. Yesterday, Rigetti introduced a new family of gates that reduces circuit depth required on some problems and D-Wave struck a deal with NEC to coll Read more…

By John Russell

How Formula 1 Used Cloud HPC to Build the Next Generation of Racing

December 12, 2019

Formula 1, Rob Smedley explained, is maybe the biggest racing spectacle in the world, with five hundred million fans tuning in for every race. Smedley, a chief engineer with Formula 1’s performance engineering and anal Read more…

By Oliver Peckham

RPI Powers Up ‘AiMOS’ AI Supercomputer

December 11, 2019

Designed to push the frontiers of computing chip and systems performance optimized for AI workloads, an 8 petaflops (Linpack) IBM Power9-based supercomputer has been unveiled in upstate New York that will be used by IBM Read more…

By Doug Black

AWS Solution Channel

Making High Performance Computing Affordable and Accessible for Small and Medium Businesses with HPC on AWS

High performance computing (HPC) brings a powerful set of tools to a broad range of industries, helping to drive innovation and boost revenue in finance, genomics, oil and gas extraction, and other fields. Read more…

IBM Accelerated Insights

GPU Scheduling and Resource Accounting: The Key to an Efficient AI Data Center

[Connect with LSF users and learn new skills in the IBM Spectrum LSF User Community!]

GPUs are the new CPUs

GPUs have become a staple technology in modern HPC and AI data centers. Read more…

At SC19: Developing a Digital Twin

December 11, 2019

In the not too distant future, we can expect to see our skies filled with unmanned aerial vehicles (UAVs) delivering packages, maybe even people, from location to location. In such a world, there will also be a digital twin for each UAV in the fleet: a virtual model that will follow the UAV through its existence, evolving with time. Read more…

By Aaron Dubrow

Focused on ‘Silicon TAM,’ Intel Puts Gary Patton, Former GlobalFoundries CTO, in Charge of Design Enablement

December 12, 2019

Change within Intel’s upper management – and to its company mission – has continued as a published report has disclosed that chip technology heavyweight G Read more…

By Doug Black

Quantum Bits: Rigetti Debuts New Gates, D-Wave Cuts NEC Deal, AWS Jumps into the Quantum Pool

December 12, 2019

There’s been flurry of significant news in the quantum computing world. Yesterday, Rigetti introduced a new family of gates that reduces circuit depth require Read more…

By John Russell

RPI Powers Up ‘AiMOS’ AI Supercomputer

December 11, 2019

Designed to push the frontiers of computing chip and systems performance optimized for AI workloads, an 8 petaflops (Linpack) IBM Power9-based supercomputer has Read more…

By Doug Black

At SC19: Developing a Digital Twin

December 11, 2019

In the not too distant future, we can expect to see our skies filled with unmanned aerial vehicles (UAVs) delivering packages, maybe even people, from location to location. In such a world, there will also be a digital twin for each UAV in the fleet: a virtual model that will follow the UAV through its existence, evolving with time. Read more…

By Aaron Dubrow

Intel’s Jim Clarke on its New Cryo-controller and why Intel isn’t Late to the Quantum Party

December 9, 2019

Intel today introduced the ‘first-of-its-kind’ cryo-controller chip for quantum computing and previewed a cryo-prober tool for characterizing quantum proces Read more…

By John Russell

On the Spack Track @SC19

December 5, 2019

At the annual supercomputing conference, SC19 in Denver, Colorado, there were Spack events each day of the conference. As a reflection of its grassroots heritage, nine sessions were planned by more than a dozen thought leaders from seven organizations, including three U.S. national Department of Energy (DOE) laboratories and Sylabs... Read more…

By Elizabeth Leake

Intel’s New Hyderabad Design Center Targets Exascale Era Technologies

December 3, 2019

Intel's Raja Koduri was in India this week to help launch a new 300,000 square foot design and engineering center in Hyderabad, which will focus on advanced com Read more…

By Tiffany Trader

AWS Debuts 7nm 2nd-Gen Graviton Arm Processor

December 3, 2019

The “x86 Big Bang,” in which market dominance of the venerable Intel CPU has exploded into fragments of processor options suited to varying workloads, has n Read more…

By Doug Black

Using AI to Solve One of the Most Prevailing Problems in CFD

October 17, 2019

How can artificial intelligence (AI) and high-performance computing (HPC) solve mesh generation, one of the most commonly referenced problems in computational engineering? A new study has set out to answer this question and create an industry-first AI-mesh application... Read more…

By James Sharpe

D-Wave’s Path to 5000 Qubits; Google’s Quantum Supremacy Claim

September 24, 2019

On the heels of IBM’s quantum news last week come two more quantum items. D-Wave Systems today announced the name of its forthcoming 5000-qubit system, Advantage (yes the name choice isn’t serendipity), at its user conference being held this week in Newport, RI. Read more…

By John Russell

DARPA Looks to Propel Parallelism

September 4, 2019

As Moore’s law runs out of steam, new programming approaches are being pursued with the goal of greater hardware performance with less coding. The Defense Advanced Projects Research Agency is launching a new programming effort aimed at leveraging the benefits of massive distributed parallelism with less sweat. Read more…

By George Leopold

Ayar Labs to Demo Photonics Chiplet in FPGA Package at Hot Chips

August 19, 2019

Silicon startup Ayar Labs continues to gain momentum with its DARPA-backed optical chiplet technology that puts advanced electronics and optics on the same chip Read more…

By Tiffany Trader

SC19: IBM Changes Its HPC-AI Game Plan

November 25, 2019

It’s probably fair to say IBM is known for big bets. Summit supercomputer – a big win. Red Hat acquisition – looking like a big win. OpenPOWER and Power processors – jury’s out? At SC19, long-time IBMer Dave Turek sketched out a different kind of bet for Big Blue – a small ball strategy, if you’ll forgive the baseball analogy... Read more…

By John Russell

Cray, Fujitsu Both Bringing Fujitsu A64FX-based Supercomputers to Market in 2020

November 12, 2019

The number of top-tier HPC systems makers has shrunk due to a steady march of M&A activity, but there is increased diversity and choice of processing compon Read more…

By Tiffany Trader

Crystal Ball Gazing: IBM’s Vision for the Future of Computing

October 14, 2019

Dario Gil, IBM’s relatively new director of research, painted a intriguing portrait of the future of computing along with a rough idea of how IBM thinks we’ Read more…

By John Russell

Kubernetes, Containers and HPC

September 19, 2019

Software containers and Kubernetes are important tools for building, deploying, running and managing modern enterprise applications at scale and delivering enterprise software faster and more reliably to the end user — while using resources more efficiently and reducing costs. Read more…

By Daniel Gruber, Burak Yenier and Wolfgang Gentzsch, UberCloud

Leading Solution Providers

SC 2019 Virtual Booth Video Tour

AMD
AMD
CEJN
CJEN
DDN
DDN
MELLANOX
MELLANOX
ONE STOP SYSTEMS
ONE STOP SYSTEMS
PANASAS
PANASAS
SIX NINES IT
SIX NINES IT
VERNE GLOBAL
VERNE GLOBAL
WEKAIO
WEKAIO

Intel Debuts New GPU – Ponte Vecchio – and Outlines Aspirations for oneAPI

November 17, 2019

Intel today revealed a few more details about its forthcoming Xe line of GPUs – the top SKU is named Ponte Vecchio and will be used in Aurora, the first plann Read more…

By John Russell

Dell Ramps Up HPC Testing of AMD Rome Processors

October 21, 2019

Dell Technologies is wading deeper into the AMD-based systems market with a growing evaluation program for the latest Epyc (Rome) microprocessors from AMD. In a Read more…

By John Russell

SC19: Welcome to Denver

November 17, 2019

A significant swath of the HPC community has come to Denver for SC19, which began today (Sunday) with a rich technical program. As is customary, the ribbon cutt Read more…

By Tiffany Trader

When Dense Matrix Representations Beat Sparse

September 9, 2019

In our world filled with unintended consequences, it turns out that saving memory space to help deal with GPU limitations, knowing it introduces performance pen Read more…

By James Reinders

Cerebras to Supply DOE with Wafer-Scale AI Supercomputing Technology

September 17, 2019

Cerebras Systems, which debuted its wafer-scale AI silicon at Hot Chips last month, has entered into a multi-year partnership with Argonne National Laboratory and Lawrence Livermore National Laboratory as part of a larger collaboration with the U.S. Department of Energy... Read more…

By Tiffany Trader

With the Help of HPC, Astronomers Prepare to Deflect a Real Asteroid

September 26, 2019

For years, NASA has been running simulations of asteroid impacts to understand the risks (and likelihoods) of asteroids colliding with Earth. Now, NASA and the European Space Agency (ESA) are preparing for the next, crucial step in planetary defense against asteroid impacts: physically deflecting a real asteroid. Read more…

By Oliver Peckham

Jensen Huang’s SC19 – Fast Cars, a Strong Arm, and Aiming for the Cloud(s)

November 20, 2019

We’ve come to expect Nvidia CEO Jensen Huang’s annual SC keynote to contain stunning graphics and lively bravado (with plenty of examples) in support of GPU Read more…

By John Russell

IBM Opens Quantum Computing Center; Announces 53-Qubit Machine

September 19, 2019

Gauging progress in quantum computing is a tricky thing. IBM yesterday announced the opening of the IBM Quantum Computing Center in New York, with five 20-qubit Read more…

By John Russell

  • arrow
  • Click Here for More Headlines
  • arrow
Do NOT follow this link or you will be banned from the site!
Share This