New cluster hardware¶
We have recently made a substantial investment in new additions to the Apocrita cluster, in the form of sdv skylake nodes, fast flash-based storage, networking, and additional GPU nodes.
Decommissioning of old ccn nodes¶
The ccn nodes have been removed to make way for the new sdv nodes. The nodes were very old, had become unreliable, and were an inefficient use of space and power.
Since these nodes were lacking support for many modern CPU instruction sets, we advise that any programs previously compiled on the ccn nodes should be recompiled on the newer nodes, for performance and compatibility reasons.
We identified a problem with the
openmpi/2.0.2-gcc module and are planning
to remove it, as the correct interface was not being used for the MPI
communication between nodes. This resulted in potentially much slower
communication and consequently jobs taking longer to run.
Programs should be rebuilt against the other available openmpi modules which correctly select the Infiniband interconnect as default for communication. Recent users of this module have been contacted directly.
For more information about deprecated modules, see here.