HAL, Summit and the Songs of Black Holes

By Oliver Peckham

October 6, 2020

The idea of gravitational waves rippling through the fabric of spacetime had been proposed for nearly a century before lightless waves from a collision between two black holes finally appeared on detectors at the Laser Interferometer Gravitational-Wave Observatory (LIGO) in 2015. Since then, the astrophysics community has been racing to identify more gravitational waves, better understand them and use the resulting data to make inferences about other elements of the universe. Now, a team from the National Center for Supercomputing Applications (NCSA) is using supercomputers to train neural networks to understand gravitational waves at a fraction of the computational cost.

At NCSA, Dr. Eliu Huerta leads the Gravity Group and the Center for Artificial Intelligence Innovation. Huerta and his colleagues have spent the last several years using innovative techniques to process the massive amount of data that is produced by each of LIGO’s fifty-plus gravitational wave observations since 2015.

The songs of black holes

“We have been exploring the use of AI to study black hole noises,” Huerta said in an interview with HPCwire. “You can think of these as songs or music that are very contaminated by noise. The question that we have now is: … what can we learn from these signals? One of the big things is where they come from – were they originated by the explosion of a star … or are these black holes formed by mergers with other black holes? And one way to figure this out is by measuring how fast they rotate.”

Scientific visualization of the collision of two black holes, numerically simulated by the open source, numerical relativity, community software, the Einstein Toolkit. Video courtesy of Roland Haas and Eliu Huerta.

“This is a computational challenge, to study this parameter,” he continued. “You … need a ton of waveforms to describe different scenarios, like ‘the two black holes have the same mass,’ ‘one is heavier than the other,’ ‘one is rotating faster than the other,’ et cetera. So you need a lot of different modal signals to study this type of scenario. Now, using traditional approaches, this is very computationally intensive. So we started a program in NCSA where we combine AI and high-performance computing for an accelerated type of analysis.”

Since 2017, Huerta’s team had been suggesting that neural networks were ideal for gravitational wave reconstruction due to their scalability and high dimensional parameter space. With the advent of GPU-accelerated computing, Huerta said, “it was a great opportunity to show that our claims were true.”

Testing the limits of scalability

Setting out to train a neural network to determine the properties of merging black holes, the team began their work on HAL, an in-house NCSA cluster with 16 IBM nodes, each equipped with two IBM Power9 CPUs, 256 GB of memory and four Nvidia V100 GPUs. Huerta estimates that the team spent “thousands” of node hours on HAL, eventually scaling their implementation to all 64 of the cluster’s GPUs and training the model over the course of 12 hours.

The Summit supercomputer.

Then, the team took a step up – to Summit, the most powerful supercomputer in the U.S. Summit’s 4,608 IBM nodes each host two IBM Power9 CPUs and six Nvidia Volta GPUs, delivering 148.6 Linpack petaflops of computing power. Receiving around 10,000 node hours of time on Summit through a Director’s Discretionary allocation from Oak Ridge National Laboratory (ORNL), the team began scaling up their work on the massive supercomputer – first on 128 nodes, then on 256 nodes.

“Using over 1,500 GPUs, we finished the training of these neural networks in about one hour,” Huerta said. “Why is this exciting, you may think? Number one: we show that we can effectively use large-scale systems that are tailored for AI research.” Further, he explained, “the models we are proposing are no longer naive models where you just propose an architecture and hope for the best; we now encode domain knowledge into the architecture of the neural nets and how we train them – this is very unique. And on top of that, we are able to constrain how fast the two black holes rotate in a way that no other algorithm can achieve right now.”

The team also demonstrated strong scaling up to 1,024 nodes – which, on Summit, equates to over 6,000 GPUs. Huerta contrasted the workflows: training a neural net across a single hour on Summit, then processing thousands of signals per second using the trained model – versus processing “just a handful” of signals per second with existing algorithms. 

“We accomplished this because our colleagues at Oak Ridge, who are collaborating with IBM and Nvidia experts, were willing to help us set up everything in the machine,” Huerta said. 

The team at ORNL also recognized the suitability of Summit for Huerta’s work. “Summit’s leadership-class capabilities and AI-friendly architecture were ideal for the team to grow and accelerate the exploration,” said Arjun Shankar, leader of the Advanced Data and Workflow Group at the Oak Ridge Leadership Computing Facility (OLCF), in an interview with ORNL’s Katie Bethea.

What’s next

While all of the team’s 10,000 node hours on Summit have been used, Huerta hopes to return to the machine soon. “The next step is to go again and play this game,” he said, “but now including all these additional corrections to the shape of the waveforms.” These waveforms, he explained, were too computationally intensive to include in the initial round of training on Summit, but when added, will increase the dimensionality of the neural net. The neural net is also updated and improved every few hours with new observations from LIGO, which are incorporated via transfer learning without necessitating a full-fledged retraining of the model.

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!

White House Scientific Integrity Report Addresses AI and ML Ethics

January 26, 2022

Earlier this month, the White House Office of Science and Technology Policy (OSTP) Scientific Integrity Task Force released a report titled “Protecting the Integrity of Government Science.” While broad-based and over Read more…

IBM Quantum Debuts Classical Entanglement Forging to Expand Simulation Capabilities

January 26, 2022

IBM last week reported a new technique – entanglement forging – that uses both quantum and classical computing resources to double the size of select simulation problems that can be solved on current quantum computer Read more…

Lenovo Launches Its TruScale HPC as a Service Offering

January 26, 2022

Lenovo today announced TruScale High Performance Computing as a Service (HPCaaS), which it says will offer a “cloud-like experience” to HPC organizations of all sizes. The new HPC-as-a-Service is part of the TruScale Read more…

Ceremorphic Touts Its HPC/AI Silicon Technology as It Exits Stealth

January 25, 2022

In a market still filling with fledging silicon chips, Ceremorphic, Inc. has exited stealth and is telling the world about what it calls its patented new ThreadArch multi-thread processor technology that is intended to h Read more…

Quantum Watch: Neutral Atoms Draw Growing Attention as Promising Qubit Technology

January 25, 2022

Currently, there are many qubit technologies vying for sway in quantum computing. So far, superconducting (IBM, Google) and trapped ion (IonQ, Quantinuum) have dominated the conversation. Microsoft’s proposed topologic Read more…

AWS Solution Channel

Register for the AWS “Speeds n’ Feeds” event on Feb. 9th

Since the debut of the first ‘Beowulf’ cluster in 1994, HPC has been a race between technologists squeezing as much performance as possible from hardware, and scale economics driving mass-production prices to affordable levels. Read more…

Meta’s Massive New AI Supercomputer Will Be ‘World’s Fastest’

January 24, 2022

Fresh off its rebrand last October, Meta (née Facebook) is putting muscle behind its vision of a metaversal future with a massive new AI supercomputer called the AI Research SuperCluster (RSC). Meta says that RSC will b Read more…

Lenovo Launches Its TruScale HPC as a Service Offering

January 26, 2022

Lenovo today announced TruScale High Performance Computing as a Service (HPCaaS), which it says will offer a “cloud-like experience” to HPC organizations of Read more…

Ceremorphic Touts Its HPC/AI Silicon Technology as It Exits Stealth

January 25, 2022

In a market still filling with fledging silicon chips, Ceremorphic, Inc. has exited stealth and is telling the world about what it calls its patented new Thread Read more…

Quantum Watch: Neutral Atoms Draw Growing Attention as Promising Qubit Technology

January 25, 2022

Currently, there are many qubit technologies vying for sway in quantum computing. So far, superconducting (IBM, Google) and trapped ion (IonQ, Quantinuum) have Read more…

Meta’s Massive New AI Supercomputer Will Be ‘World’s Fastest’

January 24, 2022

Fresh off its rebrand last October, Meta (née Facebook) is putting muscle behind its vision of a metaversal future with a massive new AI supercomputer called t Read more…

IBM Watson Health Finally Sold by IBM After 11 Months of Rumors

January 21, 2022

IBM has sold its underachieving IBM Watson Health unit for an undisclosed price tag to a global investment firm after almost a year’s worth of rumors that sai Read more…

Supercomputer Analysis Shows the Atmospheric Reach of the Tonga Eruption

January 21, 2022

On Saturday, an enormous eruption on the volcanic islands of Hunga Tonga and Hunga Haʻapai shook the Pacific Ocean. The explosion, which could be heard six tho Read more…

NSB Issues US State of Science and Engineering 2022 Report

January 20, 2022

This week the National Science Board released its biannual U.S. State of Science and Engineering 2022 report, as required by the NSF Act. Broadly, the report presents a near-term view of S&E based mostly on 2019 data. To a large extent, this year’s edition echoes trends from the last few reports. The U.S. is still a world leader in R&D spending and S&E education... Read more…

Multiverse Targets ‘Quantum Computing for the Masses’

January 19, 2022

The race to deliver quantum computing solutions that shield users from the underlying complexity of quantum computing is heating up quickly. One example is Multiverse Computing, a European company, which today launched the second financial services product in its Singularity product group. The new offering, Fair Price, “delivers a higher accuracy in fair price calculations for financial... Read more…

IonQ Is First Quantum Startup to Go Public; Will It be First to Deliver Profits?

November 3, 2021

On October 1 of this year, IonQ became the first pure-play quantum computing start-up to go public. At this writing, the stock (NYSE: IONQ) was around $15 and its market capitalization was roughly $2.89 billion. Co-founder and chief scientist Chris Monroe says it was fun to have a few of the company’s roughly 100 employees travel to New York to ring the opening bell of the New York Stock... Read more…

US Closes in on Exascale: Frontier Installation Is Underway

September 29, 2021

At the Advanced Scientific Computing Advisory Committee (ASCAC) meeting, held by Zoom this week (Sept. 29-30), it was revealed that the Frontier supercomputer is currently being installed at Oak Ridge National Laboratory in Oak Ridge, Tenn. The staff at the Oak Ridge Leadership... Read more…

AMD Launches Milan-X CPU with 3D V-Cache and Multichip Instinct MI200 GPU

November 8, 2021

At a virtual event this morning, AMD CEO Lisa Su unveiled the company’s latest and much-anticipated server products: the new Milan-X CPU, which leverages AMD’s new 3D V-Cache technology; and its new Instinct MI200 GPU, which provides up to 220 compute units across two Infinity Fabric-connected dies, delivering an astounding 47.9 peak double-precision teraflops. “We're in a high-performance computing megacycle, driven by the growing need to deploy additional compute performance... Read more…

Intel Reorgs HPC Group, Creates Two ‘Super Compute’ Groups

October 15, 2021

Following on changes made in June that moved Intel’s HPC unit out of the Data Platform Group and into the newly created Accelerated Computing Systems and Graphics (AXG) business unit, led by Raja Koduri, Intel is making further updates to the HPC group and announcing... Read more…

Nvidia Buys HPC Cluster Management Company Bright Computing

January 10, 2022

Graphics chip powerhouse Nvidia today announced that it has acquired HPC cluster management company Bright Computing for an undisclosed sum. Unlike Nvidia’s bid to purchase semiconductor IP company Arm, which has been stymied by regulatory challenges, the Bright deal is a straightforward acquisition that aims to expand... Read more…

D-Wave Embraces Gate-Based Quantum Computing; Charts Path Forward

October 21, 2021

Earlier this month D-Wave Systems, the quantum computing pioneer that has long championed quantum annealing-based quantum computing (and sometimes taken heat fo Read more…

Killer Instinct: AMD’s Multi-Chip MI200 GPU Readies for a Major Global Debut

October 21, 2021

AMD’s next-generation supercomputer GPU is on its way – and by all appearances, it’s about to make a name for itself. The AMD Radeon Instinct MI200 GPU (a successor to the MI100) will, over the next year, begin to power three massive systems on three continents: the United States’ exascale Frontier system; the European Union’s pre-exascale LUMI system; and Australia’s petascale Setonix system. Read more…

Three Chinese Exascale Systems Detailed at SC21: Two Operational and One Delayed

November 24, 2021

Details about two previously rumored Chinese exascale systems came to light during last week’s SC21 proceedings. Asked about these systems during the Top500 media briefing on Monday, Nov. 15, list author and co-founder Jack Dongarra indicated he was aware of some very impressive results, but withheld comment when asked directly if he had... Read more…

Leading Solution Providers

Contributors

Lessons from LLVM: An SC21 Fireside Chat with Chris Lattner

December 27, 2021

Today, the LLVM compiler infrastructure world is essentially inescapable in HPC. But back in the 2000 timeframe, LLVM (low level virtual machine) was just getting its start as a new way of thinking about how to overcome shortcomings in the Java Virtual Machine. At the time, Chris Lattner was a graduate student of... Read more…

2021 Gordon Bell Prize Goes to Exascale-Powered Quantum Supremacy Challenge

November 18, 2021

Today at the hybrid virtual/in-person SC21 conference, the organizers announced the winners of the 2021 ACM Gordon Bell Prize: a team of Chinese researchers leveraging the new exascale Sunway system to simulate quantum circuits. The Gordon Bell Prize, which comes with an award of $10,000 courtesy of HPC pioneer Gordon Bell, is awarded annually... Read more…

Meta’s Massive New AI Supercomputer Will Be ‘World’s Fastest’

January 24, 2022

Fresh off its rebrand last October, Meta (née Facebook) is putting muscle behind its vision of a metaversal future with a massive new AI supercomputer called t Read more…

Nvidia Defends Arm Acquisition Deal: a ‘Once-in-a-Generation Opportunity’

January 13, 2022

GPU-maker Nvidia is continuing to try to keep its proposed acquisition of British chip IP vendor Arm Ltd. alive, despite continuing concerns from several governments around the world. In its latest action, Nvidia filed a 29-page response to the U.K. government to point out a list of potential benefits of the proposed $40 billion deal. Read more…

Julia Update: Adoption Keeps Climbing; Is It a Python Challenger?

January 13, 2021

The rapid adoption of Julia, the open source, high level programing language with roots at MIT, shows no sign of slowing according to data from Julialang.org. I Read more…

Top500: No Exascale, Fugaku Still Reigns, Polaris Debuts at #12

November 15, 2021

No exascale for you* -- at least, not within the High-Performance Linpack (HPL) territory of the latest Top500 list, issued today from the 33rd annual Supercomputing Conference (SC21), held in-person in St. Louis, Mo., and virtually, from Nov. 14–19. "We were hoping to have the first exascale system on this list but that didn’t happen," said Top500 co-author... Read more…

TACC Unveils Lonestar6 Supercomputer

November 1, 2021

The Texas Advanced Computing Center (TACC) is unveiling its latest supercomputer: Lonestar6, a three peak petaflops Dell system aimed at supporting researchers Read more…

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…

  • arrow
  • Click Here for More Headlines
  • arrow
HPCwire