Cerebras Debuts AI Supercomputer-on-a-Wafer

By Tiffany Trader

August 27, 2019

Could wafer scale silicon from Cerebras Systems be the first “supercomputer on a chip” worthy of the designation? Last week at Hot Chips at Stanford University, the Silicon Valley startup debuted the largest chip ever built, a 46,225 square millimeter silicon wafer packing 1.2 trillion transistors. Cerebras says the chip’s 400,000 AI-optimized cores can train models 100-1,000 times faster than the current leading AI chip, Nvidia’s V100 GPU.

The Wafer Scale Engine is primarily an AI training machine, aimed to harvest sparsity, so it’s not a supercomputing machine, per se, but like other accelerators, it can work in tandem with and accelerate traditional modeling and simulation workloads. All three of the United States planned exascale-class supercomputers will support AI and data analytics capabilities.

To manufacture its Wafer Scale Engine, which is 57x larger than the current biggest chip (Nvidia’s GV100 GPU), Cerebras, working with TSMC’s 16-nm node, starts with a 300 mm wafer and removes the largest possible square, creating a single silicon chip with 400,000 sparse linear algebra cores, i.e., SLA cores, designed for sparse workloads like deep learning. The integration of these cores into a unified array on a single piece of silicon enables models to be trained in minutes, says Cerebras.

“We can map the entire neural network onto our compute array, we don’t put one layer, save it, another layer, save it. That allows us to achieve model parallel performance and scale linearly,” said Cerebras Founder and CEO Andrew Feldman in an interview with HPCwire. Feldman was the key figure behind Seamicro, which created the Atom-based microserver over a decade ago.

Cerebras’ wafer-scale engine has total of 18 gigabytes of on chip SRAM accessible within a single clock cycle, providing an aggregate 9 petabytes per second of memory bandwidth. An on-chip, all-hardware mesh-connected communication network delivers an aggregate bandwidth of 100 petabits per second.

Yield was one of the biggest challenges that Cerebras’ engineers, working closely with TSMC, had to overcome. Feldman counts it as one of the five major hurdles, along with cross-die connectivity, thermal expansion, packaging and cooling.

“Those were historically the five reasons why in the past 60 years, nobody could make one of these,” he said. “Cross-die connectivity and yield were the hardest. Once you’ve you succeeded, in that, you had to grapple with thermal expansion, packaging and cooling.”

Cerebras’ Wafer Scale Engine is comprised of 84 processing tiles, acting as one device

Cerebras invented a technique as part of the lithographic process to lay thousands of communications links across every scribe line. The result, said Feldman, is that rather than behaving like one-hundred chips [84 specifically], the wafer-scale engine behaves like 400,000 cores. “The software has no knowledge of whether it’s on one chip or another chip; it just sees this array,” the CEO said. Cerebras collaborated with TSMC for more than two years to develop the necessary lithographic techniques.

Cerebras can reportedly yield every wafer that TSMC delivers; 100 percent yield. An array of repeated identical tiles is built into the wafer, resulting in 400,000 very small cores, enabling redundancy.

“When it comes to yield, redundancy is your friend,” said Sean Li, chief architect and co-founder, in his Hot Chips talk.

Only 1.5 percent of the overall die is dedicated to spare cores and links, and flaws can be circumvented using these spares.

The next challenge was getting this wafer-size chip onto a motherboard, and dealing with the coefficient of thermal expansion; in other words how do you prevent a silicon chip this size from cracking as the fiberglass printed circuit board expands? Cerebras says it invented a material and a new type of connector to absorb some of that difference even when the two elements were no longer plumb.

Cerebras Wafer Scale Engine (WSE) manufacturing process

Nearly every step of the manufacturing process had to be rethought and customized. “Now that we had the silicon connector, and a printed circuit board, we had another problem nobody else had ever encountered, which is nobody’s been able to package this,” said Feldman. “Nobody had a cold plate for it. Nobody knew how to design a PCB that was appropriate for it. And there were no tools in the manufacturing supply chain that allowed us to achieve the alignment we needed, that had the handling…. We had to invent tools that carried a wafer, we had to invent equipment to qualify and test whole wafers. We had to invent the software that did alignment, all of this so that we could yield a wafer. The final problem was how do you power and how do you cool it.”

The chip is too large for power or cooling to be sent across horizontally, so a third dimension, what Cerebras calls the Z dimension, was used in both cases. With this technique, power isn’t delivered across the PCB, it’s delivered through it. The PCBs have thousands of little holes, through-silicon-vias, and power is delivered through the via so the distance is not very far.

For cooling, rather than running cool water or air across it, cool water is punched down using a copper cold plate with a grid of tiny fins. Each die reticle cooling area contains about 100 fins, so that’s roughly 840 fins ferrying away the heat. The liquid drops down into a heat exchanger that uses air to cool the water. First-gen cold plate technology is not for the faint of heart, but Cerebras reports they’ve had it working “for years” now.

Cerebras has a full system under development and says it has been running customer workloads for months; its first customer shipment is scheduled for early September. Cerebras expects to reveal details of its system at Supercomputing in November with customers in the HPC/supercomputing space. The company reports it is currently clustering its wafer-scale chip nodes, using 100 Gigabit Ethernet.

Hopefully we’ll learn the clock speed of the chip as well as the power consumption for the complete system when it is announced. It’s been estimated that the chip will use 14-15 kilowatts of power, which isn’t unreasonable if it can really do the AI training work of 100-1,000 GPUs. As a point of comparison, the DGX-2 has a max power draw of 10 kilowatts — necessary to drive the 16 V100s, a couple Platinum Xeons, the NVSwitch, eight InfiniBand ports, plus NVMe storage.

Cerebras has been quietly developing its technology since 2015; it has secured $112 million in venture funding and has a staff of nearly 200. CEO Feldman, Chief Architect Sean Li, CTO Gary Lauterback and others in the core leadership team all hail from Seamicro, which was acquired by AMD in 2012 for $355 million.

“We got a little bit lucky in 2007, when Gary and I started Seamicro, but hardware was at a nadir in the valley. Every venture capitalist had their new guy from VMware, who just thought the answer was another virtual machine, and didn’t understand hardware at all. By 2016, we were back on the rise. And people understood that if you want to go fast, you need [better] hardware,” said Feldman.

“And so there was a willingness to engage in new architectures and willingness to engage in new system design, and that’s really important. I don’t think you can achieve the type of performance that we aspire to if you just build a chip; you’re going to put it in somebody else’s server, and you’re going to put your Ferrari in a Volkswagen chassis. And you’re going to get Volkswagen performance. If you want to build a Ferrari, you need to think about how to feed it. And its handling and its steering and every last aspect. And that’s why we’re system builders; that’s what we thought we needed to do to do this.”

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!

Penguin Computing Brings Cascade Lake-AP to OCP Form Factor

July 7, 2020

Penguin Computing, a subsidiary of SMART Global Holdings, Inc., is announcing a new Tundra server, Tundra AP, that is the first to implement the Intel Xeon Scalable 9200 series processors (codenamed Cascade Lake-AP) in t Read more…

By Tiffany Trader

Google Cloud Debuts 16-GPU Ampere A100 Instances

July 7, 2020

On the heels of the Nvidia's Ampere A100 GPU launch in May, Google Cloud is announcing alpha availability of the A100 "Accelerator Optimized" VM A2 instance family on Google Compute Engine. The instances are powered by t Read more…

By Tiffany Trader

Q&A: HLRS’s Bastian Koller Tackles HPC and Industry in Germany and Europe

July 6, 2020

HPCwire: Let's start with HLRS and work our way up to the European scale. HLRS has stood out in the HPC world for its support of both scientific and industrial research. Can you discuss key developments in recent years? Read more…

By Steve Conway, Hyperion

The Barcelona Supercomputing Center Offers a Virtual Tour of Its MareNostrum Supercomputer

July 6, 2020

With the COVID-19 pandemic continuing to threaten the world and disrupt normal operations, facility tours remain a little difficult to operate, with many supercomputing centers having shuttered facility tours for visitor Read more…

By Oliver Peckham

What’s New in Computing vs. COVID-19: Fugaku, Congress, De Novo Design & More

July 2, 2020

Supercomputing, big data and artificial intelligence are crucial tools in the fight against the coronavirus pandemic. Around the world, researchers, corporations and governments are urgently devoting their computing reso Read more…

By Oliver Peckham

AWS Solution Channel

Maxar Builds HPC on AWS to Deliver Forecasts 58% Faster Than Weather Supercomputer

When weather threatens drilling rigs, refineries, and other energy facilities, oil and gas companies want to move fast to protect personnel and equipment. And for firms that trade commodity shares in oil, precious metals, crops, and livestock, the weather can significantly impact their buy-sell decisions. Read more…

Intel® HPC + AI Pavilion

Supercomputing the Pandemic: Scientific Community Tackles COVID-19 from Multiple Perspectives

Since their inception, supercomputers have taken on the biggest, most complex, and most data-intensive computing challenges—from confirming Einstein’s theories about gravitational waves to predicting the impacts of climate change. Read more…

OpenPOWER Reboot – New Director, New Silicon Partners, Leveraging Linux Foundation Connections

July 2, 2020

Earlier this week the OpenPOWER Foundation announced the contribution of IBM’s A21 Power processor core design to the open source community. Roughly this time last year, IBM announced open sourcing its Power instructio Read more…

By John Russell

Google Cloud Debuts 16-GPU Ampere A100 Instances

July 7, 2020

On the heels of the Nvidia's Ampere A100 GPU launch in May, Google Cloud is announcing alpha availability of the A100 "Accelerator Optimized" VM A2 instance fam Read more…

By Tiffany Trader

Q&A: HLRS’s Bastian Koller Tackles HPC and Industry in Germany and Europe

July 6, 2020

HPCwire: Let's start with HLRS and work our way up to the European scale. HLRS has stood out in the HPC world for its support of both scientific and industrial Read more…

By Steve Conway, Hyperion

OpenPOWER Reboot – New Director, New Silicon Partners, Leveraging Linux Foundation Connections

July 2, 2020

Earlier this week the OpenPOWER Foundation announced the contribution of IBM’s A21 Power processor core design to the open source community. Roughly this time Read more…

By John Russell

Hyperion Forecast – Headwinds in 2020 Won’t Stifle Cloud HPC Adoption or Arm’s Rise

June 30, 2020

The semiannual taking of HPC’s pulse by Hyperion Research – late fall at SC and early summer at ISC – is a much-watched indicator of things come. This yea Read more…

By John Russell

Racism and HPC: a Special Podcast

June 29, 2020

Promoting greater diversity in HPC is a much-discussed goal and ostensibly a long-sought goal in HPC. Yet it seems clear HPC is far from achieving this goal. Re Read more…

Top500 Trends: Movement on Top, but Record Low Turnover

June 25, 2020

The 55th installment of the Top500 list saw strong activity in the leadership segment with four new systems in the top ten and a crowning achievement from the f Read more…

By Tiffany Trader

ISC 2020 Keynote: Hope for the Future, Praise for Fugaku and HPC’s Pandemic Response

June 24, 2020

In stark contrast to past years Thomas Sterling’s ISC20 keynote today struck a more somber note with the COVID-19 pandemic as the central character in Sterling’s annual review of worldwide trends in HPC. Better known for his engaging manner and occasional willingness to poke prickly egos, Sterling instead strode through the numbing statistics associated... Read more…

By John Russell

ISC 2020’s Student Cluster Competition Winners Announced

June 24, 2020

Normally, the Student Cluster Competition involves teams of students building real computing clusters on the show floors of major supercomputer conferences and Read more…

By Oliver Peckham

Supercomputer Modeling Tests How COVID-19 Spreads in Grocery Stores

April 8, 2020

In the COVID-19 era, many people are treating simple activities like getting gas or groceries with caution as they try to heed social distancing mandates and protect their own health. Still, significant uncertainty surrounds the relative risk of different activities, and conflicting information is prevalent. A team of Finnish researchers set out to address some of these uncertainties by... Read more…

By Oliver Peckham

[email protected] Turns Its Massive Crowdsourced Computer Network Against COVID-19

March 16, 2020

For gamers, fighting against a global crisis is usually pure fantasy – but now, it’s looking more like a reality. As supercomputers around the world spin up Read more…

By Oliver Peckham

[email protected] Rallies a Legion of Computers Against the Coronavirus

March 24, 2020

Last week, we highlighted [email protected], a massive, crowdsourced computer network that has turned its resources against the coronavirus pandemic sweeping the globe – but [email protected] isn’t the only game in town. The internet is buzzing with crowdsourced computing... Read more…

By Oliver Peckham

Global Supercomputing Is Mobilizing Against COVID-19

March 12, 2020

Tech has been taking some heavy losses from the coronavirus pandemic. Global supply chains have been disrupted, virtually every major tech conference taking place over the next few months has been canceled... Read more…

By Oliver Peckham

Supercomputer Simulations Reveal the Fate of the Neanderthals

May 25, 2020

For hundreds of thousands of years, neanderthals roamed the planet, eventually (almost 50,000 years ago) giving way to homo sapiens, which quickly became the do Read more…

By Oliver Peckham

DoE Expands on Role of COVID-19 Supercomputing Consortium

March 25, 2020

After announcing the launch of the COVID-19 High Performance Computing Consortium on Sunday, the Department of Energy yesterday provided more details on its sco Read more…

By John Russell

Steve Scott Lays Out HPE-Cray Blended Product Roadmap

March 11, 2020

Last week, the day before the El Capitan processor disclosures were made at HPE's new headquarters in San Jose, Steve Scott (CTO for HPC & AI at HPE, and former Cray CTO) was on-hand at the Rice Oil & Gas HPC conference in Houston. He was there to discuss the HPE-Cray transition and blended roadmap, as well as his favorite topic, Cray's eighth-gen networking technology, Slingshot. Read more…

By Tiffany Trader

Honeywell’s Big Bet on Trapped Ion Quantum Computing

April 7, 2020

Honeywell doesn’t spring to mind when thinking of quantum computing pioneers, but a decade ago the high-tech conglomerate better known for its control systems waded deliberately into the then calmer quantum computing (QC) waters. Fast forward to March when Honeywell announced plans to introduce an ion trap-based quantum computer whose ‘performance’ would... Read more…

By John Russell

Leading Solution Providers

Contributors

Neocortex Will Be First-of-Its-Kind 800,000-Core AI Supercomputer

June 9, 2020

Pittsburgh Supercomputing Center (PSC - a joint research organization of Carnegie Mellon University and the University of Pittsburgh) has won a $5 million award Read more…

By Tiffany Trader

‘Billion Molecules Against COVID-19’ Challenge to Launch with Massive Supercomputing Support

April 22, 2020

Around the world, supercomputing centers have spun up and opened their doors for COVID-19 research in what may be the most unified supercomputing effort in hist Read more…

By Oliver Peckham

Nvidia’s Ampere A100 GPU: Up to 2.5X the HPC, 20X the AI

May 14, 2020

Nvidia's first Ampere-based graphics card, the A100 GPU, packs a whopping 54 billion transistors on 826mm2 of silicon, making it the world's largest seven-nanom Read more…

By Tiffany Trader

Australian Researchers Break All-Time Internet Speed Record

May 26, 2020

If you’ve been stuck at home for the last few months, you’ve probably become more attuned to the quality (or lack thereof) of your internet connection. Even Read more…

By Oliver Peckham

10nm, 7nm, 5nm…. Should the Chip Nanometer Metric Be Replaced?

June 1, 2020

The biggest cool factor in server chips is the nanometer. AMD beating Intel to a CPU built on a 7nm process node* – with 5nm and 3nm on the way – has been i Read more…

By Doug Black

15 Slides on Programming Aurora and Exascale Systems

May 7, 2020

Sometime in 2021, Aurora, the first planned U.S. exascale system, is scheduled to be fired up at Argonne National Laboratory. Cray (now HPE) and Intel are the k Read more…

By John Russell

Summit Supercomputer is Already Making its Mark on Science

September 20, 2018

Summit, now the fastest supercomputer in the world, is quickly making its mark in science – five of the six finalists just announced for the prestigious 2018 Read more…

By John Russell

TACC Supercomputers Run Simulations Illuminating COVID-19, DNA Replication

March 19, 2020

As supercomputers around the world spin up to combat the coronavirus, the Texas Advanced Computing Center (TACC) is announcing results that may help to illumina Read more…

By Staff report

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