What is an HPC cluster

An HPC cluster is a collection of many separate servers (computers), called nodes, which are connected via a fast interconnect.

There may be different types of nodes for different types of tasks.

Each of the HPC clusters listed on this site has

  • headnode or login node, where users log in
  • specialized data transfer node
  • regular compute nodes (where majority of computations is run)
  • "fat" compute nodes that have at least 1TB of memory
  • GPU nodes (on these nodes computations can be run both on CPU cores and on a Graphical Processing Unit)
  • an Infiniband switch to connect all nodes

 

All cluster nodes have the same components as a laptop or desktop: CPU cores, memory and disk space. The difference between personal computer and a cluster node is in quantity, quality and power of the components.

 

Users login from their computers to the cluster headnode using the ssh program.

 

Next: HPC clusters at ISU