Inside Six of the Newest Top 20 Supercomputers
#20 “Cheyenne” National Center for Atmospheric Research (NCAR)
nextplatform.com
November 14, 2016 Nicole Hemsoth
The National Center for Atmospheric Research in the United States is going to be replacing its current 1.5 petaflops “Yellowstone” massively parallel Xeon system with a kicker based on future Xeon chips from Intel that will weigh in at an estimated 5.34 petaflops and offer the weather and climate modeling research organization lots more oomph to run its simulations.
The HPE/SGI Cheyenne will be housed in the same Wyoming Supercomputing Center where the Yellowstone system was installed in 2012, which is located in Cheyenne, Wyoming and hence the name of the system. These two petaflops-class machines will run side-by-side for a while until the newer one is fully operational.
145,152 cores, about twice as many as what Yellowstone could deploy on workloads. But the performance improvement on real-world weather and climate modeling applications is expected to be larger. Cheyenne, at 5.34 petaflops, has about 3.6 times the peak performance of Yellowstone, at 1.5 petaflops. “We are projecting that our workloads will support 2.5X probably,” says Anke Kamrath, director of the Operations and Services Division at NCAR. “Just because you make the processors a little faster does not mean you can take advantage of all of the features.”
The plan is to have around 20 percent of the nodes have 128 GB of main memory, with the remaining 80 percent being configured with 64 GB, allowing for different parts of the cluster to run applications with differing needs for memory. The machine will have a total of 313 TB of memory, and that’s a little more than twice the aggregate main memory of Yellowstone, which stands to reason.
A system upgrade is not built into the Cheyenne deal, but the 9D enhanced hypercube topology that SGI and partner Mellanox Technology has created for the ICE XA system from SGI allows for an easy upgrade if NCAR just wants to expand Cheyenne at some point. (The hypercube topology allows for nodes to be added or removed from the cluster without shutting the cluster down or rewiring the network.)
“Things change so much, who knows about the future,” concedes Kamrath. “We could use Knights Landing, there are ARM processors coming out. I expect for our next procurement there will be a much higher diversity of things because there is more competition coming, which is a good thing.”
The ICE XA design crams 144 nodes and 288 sockets into a single rack, and Cheyenne will have 28 racks in total. The ICE XA machines, which debuted in November 2014 and which have had a couple of big wins to date, offer a water-cooled variant and NCAR will be making use of this to increase the efficiency of the overall system. In fact, NCAR expects that Cheyenne will be able to do more than 3 gigaflops per watt, which is more than three times as energy efficient as the Yellowstone machine it replaces. |
