Hardware Overview

Hardware Overview

ARIS is the name of the Greek supercomputer, deployed and operated by GRNET (Greek Research and Technology Network) in Athens. ARIS consists of 532 computational nodes seperated in four “islands” as listed here:

  • 426 thin nodes: Regular compute nodes without accelerator.
  • 44 gpu nodes: “2 x NVIDIA Tesla k40m” accelerated nodes.
  • 18 phi nodes: “2 x INTEL Xeon Phi 7120p” accelerated nodes.
  • 44 fat nodes: Fat compute nodes have larger number of cores and memory per core than a thin node.

All the nodes are connected via Infiniband network and share 2PB GPFS storage. Access to the system is provided by two login nodes.

Nodes Summary

Node Type Count Accelerator Memory Cores
THIN nodes 426 w/o 64 GB 20@2.8 GHz (two sockets)
GPU nodes 44 dual tesla k40m 64 GB 20@2.6 GHz + 2 x K40
PHI nodes 18 dual xeon phi 7120p 64 GB 20@2.6 GHz + 2 x 7120p
FAT nodes 44 w/o 512 GB 40@2.4 GHz (four sockets)

General Information

Architecture x86-64
Operating System Redhat/Centos 6.7
Interconnect
Technology Infiniband FDR
Topology Fat tree
Bandwidth [Gb/s] 56
Storage
Type IBM GPFS
Size [PByte] 1
Bandwidth [GB/s] 6
System Software
Operating system RedHat/Centos Linux 6.7
Batch system SLURM
System Management xCat IBM
Monitoring Nagios, Ganglia

Technical Info

Thin nodes

The 426 thin compute nodes (thin node island) have a theoretical peak performance (Rpeak) of 190,85 TFlops and a sustained performance (Rmax) of 179,73 TFlops on the Linpack benchmark. The systems was ranked #468 in the Top500 list of most powerful systems in the world when it was installed (June 2015 iteration). The thin island is best suited for high-scalable applications utilizing MPI or hybrid MPI/OpenMP programming.

THIN nodes technical information
Architecture x86-64
System IBM NeXtScale nx360 M4
Total number of nodes 426
Total number of cores 8520
Total amount of RAM [TByte] 27
Total Linpack Performance [TFlop/s] 180
Components
Processor Type Ivy Bridge - Intel Xeon E5-2680v2
Nominal Frequency [GHz] 2.8
Processors per Node 2
Cores per Processor 10
Cores per Node 20
Hyperthreading OFF
Memory
Memory per Node [GByte] 64

GPU nodes

44 GPU nodes offer a combined total theoritical peak performance of 162,45 TFlops (36,61 TFlops from CPUs and 125,84 TFlops from GPUs). Each NVidia K40 GPU incorporate 2880 CUDA cores.

GPU nodes technical information
Architecture x86-64
System DELL PowerEdge R730
Total number of nodes 44
Total number of cores 880
Total number of gpus 88
Total amount of RAM [TByte] 2,8
Total Linpack Performance [TFlop/s] 83,65
Components
Processor Type Haswell - Intel(R) Xeon(R) E5-2660v3
Nominal Frequency [GHz] 2.6
Processors per Node 2
Cores per Processor 10
Cores per Node 20
Hyperthreading OFF
Accelerators
Accelerator type GPU - NVIDIA Tesla K40
Accelerators per node 2
Accelerator memory [GByte] 12
Memory
Memory per Node [GByte] 64

PHI nodes

Phi nodes are so called because they include dual Intel Xeon Phi 7120P accelerators. They offer a combined theoritical peak performance of 58,46 TFlops (14,98 TFlops from CPUs and 43,49 from the accelerators). Phi nodes are appropriate for fast scaling of existing x86 codes. Vectorized codes will take advantage of the full potential of Intel MIC architecture.

PHI nodes technical information
Architecture x86-64
System DELL PowerEdge R730
Total number of nodes 18
Total number of phi’s 36
Total number of cores 360
Total amount of RAM [TByte] 1,1
Total Linpack Performance [TFlop/s] 39,04
Components
Processor Type Haswell - Intel(R) Xeon(R) E5-2660v3
Nominal Frequency [GHz] 2.6
Processors per Node 2
Cores per Processor 10
Cores per Node 20
Hyperthreading OFF
Accelerators
Accelerator type MIC - Intel Xeon Phi Coprocessor 7120P
Accelerators per node 2
Accelerator memory [GByte] 16
Memory
Memory per Node [GByte] 64

Fat nodes

Fat nodes offer more cores and more memory per server comparing with the regular two-socket nodes (thin, phi, gpu). The total theoritical performance is 33,79 TFlops. Fat nodes are best suited for shared memory applications (e.g. OpenMP-based) and in general applications that require to perform in-memory processing of large datasets.

FAT nodes technical information
Architecture x86-64
System DELL PowerEdge R820
Total number of nodes 44
Total number of cores 1760
Total amount of RAM [TByte] 22,5
Total Linpack Performance [TFlop/s] 32,01
Components
Processor Type SandyBridge - Intel(R) Xeon(R) CPU E5-4650v2
Nominal Frequency [GHz] 2.4
Processors per Node 4
Cores per Processor 10
Cores per Node 40
Hyperthreading OFF
Memory
Memory per Node [GByte] 512

Login nodes

Login nodes
Number of Nodes 2
Processor Type Intel(R) Xeon(R) CPU E5-2640 v2
Nominal Frequency [GHz] 2.00GHz
Processors per Node 2
Cores per Processor 16
Threads per Processor 32
Hyperthreading ON
Memory per Node [GByte] 128