Theta, a 9.65 petaflops system based on the second-generation Intel® Xeon Phi™ processor, will enable breakthrough computational science and engineering research, while providing a platform to help ALCF users transition their applications to the new Intel Xeon Phi architecture.

Designed in collaboration with Intel and Cray, Theta will serve as a stepping stone to the ALCF's next leadership-class supercomputer, Aurora. Both Theta and Aurora will be massively parallel, many-core systems based on Intel processors and interconnect technology, a new memory architecture, and a Lustre-based parallel file system, all integrated by Cray’s HPC software stack.

Theta is equipped with 3,624 nodes, each containing a 64 core processor with 16 gigabytes (GB) of high-bandwidth in-package memory (MCDRAM), 192 GB of DDR4 RAM, and a 128 GB SSD. Theta’s initial parallel file system is 10 petabytes.

Theta has several features that will allow scientific codes to achieve higher performance, including:

  • High-bandwidth MCDRAM (300 - 450 GB/s depending on memory and cluster mode), with many applications running entirely in MCDRAM or using it effectively with DDR4 RAM
  • Improved single thread performance
  • Potentially much better vectorization with AVX-512
  • Large total memory per node (208 GB on Theta vs. 16 GB on Mira)

Theta System Configuration

  • 20 racks
  • 3,624 nodes
  • 231,935 cores
  • 56 TB MCDRAM
  • 679 TB DDR4
  • 453 TB SSD
  • Aries interconnect with Dragonfly configuration
  • 10 PB Lustre file system
  • Peak performance of 9.65 petaflops