Cray XK7

Cray XK7 designated the successor generation of XK6 and XT5 technology, which uses the company Cray Research for large supercomputer as a hybrid cluster of CPUs and GPUs. The system operated by the U.S. Oak Ridge National Laboratory Jaguar was gradually converted to XK7 node. After completion of the refit it was renamed Titan. The computing power increased from 2.3 to 17.59 petaflops. The upgrade cost 97 million U.S. dollars. The computer is in 200 Racks, Cabinets called housed. The supercomputer will serve the research of new biofuels, more fuel-efficient internal combustion engines, more efficient solar cells, etc.. Besides applications in the fields of medicine, geology and the exploration of new materials are planned.


The equipment of a XK7 racks may include:

  • Processors: 4 AMD Opteron 6200 - 64- processors ( 16 cores) and four Nvidia Tesla GPUs K20 are housed on a blade ( slide board); a rack has space for 24 blades, which corresponds to 96 CPUs and 96 GPUs per rack. Up to 1536 CPU cores may be located in a rack thus.
  • Memory: 16 or 32 GB of registered ECC DDR3 SDRAM per CPU; 6 GB GDDR5 per GPU
  • Internal bus: 2 Gemini ASICs per blade; a Gemini chip has 48 switch ports and is connected with HyperTransport 3.0 on the compute nodes; the topology corresponds to a three-dimensional torus geometry.
  • External I / O Interfaces: InfiniBand, 10 Gigabit Ethernet, Fibre Channel ( FC ) and Ethernet
  • Data storage system: Fibre Channel -connected disk array Fibre Channel or SATA drives
  • File system: Lustre, over Cray Data Virtualization Service also other file systems can be addressed
  • Operating system: Cray Linux Environment, a SUSE Linux Enterprise Server includes environment and Cray's Compute Node Linux
  • Dimensions: Height: 2.36 m, width 0.57 m, depth 1.44 m
  • Weight ( air-cooled): 725 kg, (with liquid cooling): 907 kg
  • Power consumption: 45 to 54.1 kW
  • Cooling: air or optional liquid cooling

Titan will consist of a total of 200 XK7 racks with 18688 CPUs and GPUs maximum of 18688.