The Atos HPCF consists of four virtually identical complexesl: AA, AB, AC and AD. In total, this HPCF features 8128 nodes:
There is an additional virtual complex, ECS, which is made from compute nodes of the 4 complexes. This is the one to be used by those users who don't have access to the full HPCF service. |
The logic structure of one of the complexes is as follows:
The most notable change with respect to the previous Cray XC40 HPCF is in the processor architecture, from Intel to AMD. Although both implement the x86_64 instruction set, the latter has many more cores.
| Cray (CCA/CCB) | Atos (AA/AB/AC/AD) | |
|---|---|---|
| CPU Architecture | Intel Broadwell | AMD EPYC Rome |
Core Frequency | 2.1 GHz | 2.5 GHz (GPIL) / 2.25 GHz (compute) |
| Cores per node (HT) | 36 (72) | 128 (256) |
| Memory per node | 128 GiB | 512 GiB (GPIL) / 256 GiB (compute) |
| Fabric interconnect | Cray Aries | Mellanox HDR InfiniBand - 100 Gbps (GPIL) / 200 Gbps (compute) |
| Operating System | Based on SLES 11 | Based on RHEL 8 |
| Batch system | PBS with ALPS | SLURM |
| Parallel Filesystem | Lustre | Lustre |
| Compilers | Cray, GNU, Intel | GNU, Intel, AOCC |
| MPI | Cray MPICH | Intel MPI, OpenMPI |