HPC

Cray XK6 super mates Opterons with Nvidia GPU workhorses

Ceepie-geepies all around


Supercomputer maker Cray has finally jumped on the GPU coprocessor bandwagon, and it looks like someone is going to have to hitch Belgian draft horses to that wagon and reinforce its axles once the XK6 hybrid super starts shipping in the fall.

Cray made a name for itself as a provider of vector processors back in the 1970s and morphed into a maker of massively parallel x64 machines with proprietary interconnects in the 2000s. With GPUs – whether they are made by Nvidia or AMD – being more like vector engines than not, the adoption of a GPU as a coprocessor is a return to its past. Or more precisely, considering that Cray is really Tera Computer plus Cray Research plus Octiga Bay, one of its pasts.

Cray didn't need GPUs to break through the petaflops barrier, but it is going to need GPUs or some kind of coprocessor to break through the exascale barrier. Barry Bolding, vice president of products at Cray, tells El Reg that "customers are a little dissatisfied that scalar performance has flattened out" in recent years, referring to the clock speeds of the x64 processors used inside of generic supercomputer clusters (usually linked by Ethernet or InfiniBand networks) or the monster machines created by Cray and Silicon Graphics using their respective "Gemini" XE and "UltraViolet" NUMAlink 5 interconnects.

"Cray has not been the first to the GPU party, but we have a very good understanding of petascale applications," Bolding boasted, adding that "putting together a box that has both CPUs and GPUs is the easy part."

In fact, says Bolding, Cray has spent more money on integrating its software stack – a custom Linux environment, its Ethernet emulation layer for the Gemini interconnect, and various development tools for parallel environments – with GPUs than it has spent redesigning the blade servers at the heart of its "Baker" family of XE6 and XE6m machines so they can adopt GPU coprocessors.

"We think that our vector experience helps," Bolding says. "The codes that were good for vectors will generally perform well on GPUs. And we really do view this as a stepping stone to exascale. GPUs are today the most effective accelerator that is available." Bolding added that Cray's future designs will not be locked into either AMD's HyperTransport or Intel's QuickPath interconnects, but rather will hang accelerators off PCI Express links. (Very soon, PCI Express 3.0 links, but not this time around.)

Cray XK6 CPU-GPU supercomputer

Cray's XK6 ceepie-geepie hybrid supercomputer

The Cray XE6 machines are based on eight-socket blade servers, complete with main memory and two Gemini interconnect ASICs. The prior generation of machines, the XT6 supers, were based on the same "Magny-Cours" Opteron 6100 processors that are used in the XE6 blades, but used the much slower and less scalable SeaStar2+ interconnect. The SeaStar2+ interconnect is the great-grandson of the "Red Storm" interconnect that Cray developed for Sandia National Laboratory, delivered in 2003, and later commercialized as the XT3.

Next page: Gemini dream

Other stories you might like

  • Experts: AI should be recognized as inventors in patent law
    Plus: Police release deepfake of murdered teen in cold case, and more

    In-brief Governments around the world should pass intellectual property laws that grant rights to AI systems, two academics at the University of New South Wales in Australia argued.

    Alexandra George, and Toby Walsh, professors of law and AI, respectively, believe failing to recognize machines as inventors could have long-lasting impacts on economies and societies. 

    "If courts and governments decide that AI-made inventions cannot be patented, the implications could be huge," they wrote in a comment article published in Nature. "Funders and businesses would be less incentivized to pursue useful research using AI inventors when a return on their investment could be limited. Society could miss out on the development of worthwhile and life-saving inventions."

    Continue reading
  • Declassified and released: More secret files on US govt's emergency doomsday powers
    Nuke incoming? Quick break out the plans for rationing, censorship, property seizures, and more

    More papers describing the orders and messages the US President can issue in the event of apocalyptic crises, such as a devastating nuclear attack, have been declassified and released for all to see.

    These government files are part of a larger collection of records that discuss the nature, reach, and use of secret Presidential Emergency Action Documents: these are executive orders, announcements, and statements to Congress that are all ready to sign and send out as soon as a doomsday scenario occurs. PEADs are supposed to give America's commander-in-chief immediate extraordinary powers to overcome extraordinary events.

    PEADs have never been declassified or revealed before. They remain hush-hush, and their exact details are not publicly known.

    Continue reading
  • Stolen university credentials up for sale by Russian crooks, FBI warns
    Forget dark-web souks, thousands of these are already being traded on public bazaars

    Russian crooks are selling network credentials and virtual private network access for a "multitude" of US universities and colleges on criminal marketplaces, according to the FBI.

    According to a warning issued on Thursday, these stolen credentials sell for thousands of dollars on both dark web and public internet forums, and could lead to subsequent cyberattacks against individual employees or the schools themselves.

    "The exposure of usernames and passwords can lead to brute force credential stuffing computer network attacks, whereby attackers attempt logins across various internet sites or exploit them for subsequent cyber attacks as criminal actors take advantage of users recycling the same credentials across multiple accounts, internet sites, and services," the Feds' alert [PDF] said.

    Continue reading

Biting the hand that feeds IT © 1998–2022