Standard node configurations (2023)

Compute node

RAM:
- >= 4 GB/core. Snellius thin nodes have 2 GB/core, which is good for many-core (MPI) jobs. For single-core (serial) jobs, less cores but more memory per core is better. 4 GB/core should be a good compromise.
- >= 256 GB total. This is good for single-core (serial) jobs.
CPU:
- SMT enabled or not? Can be beneficial for some workloads¹. In memory-bound jobs it is not helpful, altough it may allow us to buy a CPU with only half the number of cores. But note: that likely also means less on-die cache.
- 256 / 4 -> 64 cores would be the sweet spot given the above memory considerations.
- Dual socket gives double the memory channels, hence double the memory bandwidth.
- Zen 2 and Zen 3 have 8 memory channels. Zen 4 can have up to 12.
- Less cores per CPU typically means larger base clock. Hence 2x 32 cores has larger clocks than 1x 64 cores. This is good for serial jobs, as long as memory is local to the socket.
Local storage:
- Boot storage: small as possible; RAID-1
- Local storage: size on request; minimum 180 GB; SSD preferred; RAID undecided (180 GB is smallest left over space on BOSS card)
- Boot storage and local storage can land on same medium.
Ethernet:
- Connected to ethernet fabric via 1x 10 Gbit UTP.
- RoCEv2-capable NIC.
Power supply: dual. No cables needed; we have those ourselves.
Hardware support: 5 years. Next business day, they send us the part, we replace it.
Remote mgmt: required. For Dell: iDRAC with Enterprise and OpenManage.
Rackmount kit: required.

For example:

Dell PowerEdge R6525, 2x (AMD EPYC 75F3, 2.95 GHz, 32c, 256 MB cache), 256 GB RAM, €26.500 incl. VAT
Dell PowerEdge R6525, 2x (AMD EPYC 7713, 2.00 GHz, 64c, 256 MB cache), 512 GB RAM, €28.000 incl. VAT
Dell PowerEdge R6625, 2x (AMD EPYC 9454, 2.75 GHz, 48c, 256 MB cache), 384 GB RAM, €33.300 incl. VAT
Dell PowerEdge R6515, 1x (AMD EPYC 7713P, 2.00 GHz, 64c, 256 MB cache), 256 GB RAM, €12.200 incl. VAT
Dell PowerEdge R6515, 1x (AMD EPYC 7763P, 2.45 GHz, 64c, 256 MB cache), 256 GB RAM, €14.000 incl. VAT
Dell PowerEdge R6615, 1x (AMD EPYC 9654P, 2.40 GHz, 96c, 384 MB cache), 384 GB RAM, €26.500 incl. VAT