Computational Modelling Group


The University of Southampton Supercomputing facility is called Iridis. Currently the University is running two generations of Iridis supercomputers at the same time making it one of the top University owned supercomputing sites in the UK. The facility is open to research students and members of academic staff from any Faculty, who has the need for compute resources substantially greater than a standard PC. In addition, Iridis hosts the Lyceum service that offers access for undergraduate and MSc project work.

Iridis 5

Iridis is currently in its fifth generation and remains one of the largest computational facilities in the UK. In November 2017, Iridis 5 joined the elite of the world’s top 500 supercomputers and is over four times more powerful than its predecessor. Iridis 5 also includes the new Data Intensive service, 20 of Nvidia’s enterprise GPUs, and a dedicated data visualisation service.

Technical specifications for Iridis 5
  • 464 compute nodes with dual 2.0 GHz Intel Skylake processors.
  • Each compute node has 40 CPUs per node with 192 GB of DDR4 memory.
  • 20 Nvidia Tesla V100 enterprise graphics cards.
  • 40 Nvidia GTX 1080Ti consumer graphics cards.
  • 4 high-memory nodes, each with 64 cores, 768 GB of RAM and 9 TB of local HDD scratch space.
  • 4 high memory nodes running a 36 TB Hadoop/Spark service.
  • 8 high memory nodes providing a private cloud service.
  • 2 data visualisation nodes with 22 usable cores, 384 GB of RAM and an Nvidia M60 GPU. These run both windows and Linux VMs.
  • 3 login nodes with 40 cores and 384 GB of memory.
  • In total more than 20,000 processor-cores providing 1,305 TFlops peak.
  • 2.2 PB of storage run on IBM Spectrum Scale parallel file system.
  • InfiniBand network for interprocess communication

Recommended hashtag: #iridis5

Iridis 4

Whilst no longer the latest and greatest, the previous generation of Iridis is also still in operation and remains a computational workhorse. At the time of its launch in November 2012, according to the TOP500 Supercomputers issue it was ...

  • the most powerful academic supercomputer in England;
  • the second largest academic computational facility in the UK behind National Facility;
  • in Top 15 academic computational facilities in Europe;
  • in Top 30 academic computational facilities in the World;
Technical specifications for Iridis4
  • 12320 Cores (250 TFlops);
  • 16*2.6 GHz cores per node;
  • 4 GB of memory per core;
  • 4 high-memory nodes with 32 cores and 256 GB of RAM;
  • 24 Intel Xeon Phi Accelerators (25 TFlops);
  • 1.04 PB of storage with Parallel File System;
  • Infiniband network for interprocess communication;

See also Press release 15 October 2013 and video about Iridis 4.

Recommended hashtag: #iridis4

Further Information

Further Information for local users is available on Internal CMG Iridis pages. As well as documentation on how to access and use the service, it has information on training courses, background information on the facility, user forums and links to sources of further information.

Research outcome

You can get a flavour of kind of research topics enabled by Iridis from this list of scientific projects.