SMP Cluster Julia¶
Overview¶
The HPE Superdome Flex is a large shared memory node. It is especially well suited for data intensive application scenarios, for example to process extremely large data sets completely in main memory or in very fast NVMe memory.
Hardware Resources¶
The hardware specification is documented on the page HPC Resources.
Note
Julia
has been partitioned at the end of October 2024. A quarter of the hardware ressources
(CPUs and memory) are now in exclusive operation for the
DZA.
Local Temporary on NVMe Storage¶
There are 370 TB of NVMe devices installed. For immediate access for all projects, a volume of 87 TB
of fast NVMe storage is available at /nvme/1/<projectname>
. A quota of
100 GB per project on this NVMe storage is set.
With a more detailed proposal to hpc-support@tu-dresden.de on how this unique system (large shared memory + NVMe storage) can speed up their computations, a project's quota can be increased or dedicated volumes of up to the full capacity can be set up.
Hints for Usage¶
- Granularity should be a socket (28 cores)
- Can be used for OpenMP applications with large memory demands
- To use Open MPI it is necessary to export the following environment variables, so that Open MPI uses shared-memory instead of InfiniBand for message transport:
export OMPI_MCA_pml=ob1
export OMPI_MCA_mtl=^mxm
- Use
I_MPI_FABRICS=shm
so that Intel MPI doesn't even consider using InfiniBand devices itself, but only shared-memory instead