Nodes Overview¶
Apocrita runs a variety of different job types, and the cluster is comprised of different node types and queues to accommodate this. Unless you have a specific technical reason, you should avoid selecting a specific node type to run your job on. Some nodes are restricted depending on the source of funding.
The following nodes are open access, allowing jobs from any user.
| Open Access | Required variables | Count | Cores | RAM | Accessible RAM | Arch |
|---|---|---|---|---|---|---|
| ddy | 56 | 48 | 384GB | ~362GB | Intel | |
| emf | highmem | 14 | 24 | 768GB | ~741GB | Intel |
| nxv | 34 | 32 | 256GB | ~242GB | Intel | |
| nxg | gpu | 4 | 32 | 256GB | ~242GB | Intel |
| sbg (ampere) | gpu | 1 | 48 | 384GB | ~365GB | Intel |
| sbg (volta) | gpu | 3 | 32 | 384GB | ~365GB | Intel |
| sdv | infiniband=sdv-i | 32 | 24 | 192GB | ~176GB | Intel |
| sdx | 52 | 36 | 384GB | ~362GB | Intel | |
| srm | highmem | 2 | 36 | 768GB | ~741GB | Intel |
| Total | 198 | 7096 | 71.2TB |
The following nodes are restricted to specific groups controlled by the purchasers of the nodes. Requests for access to these nodes will need to be confirmed by the owner of the node before access will be granted. We additionally have a node called burst1 used for lab and training sessions, and as a burst node for extending the capacity of the cluster outside term-time.
| Restricted Access | Required variables | Count | Cores | RAM | Accessible RAM | Arch |
|---|---|---|---|---|---|---|
| ddy | 68 | 48 | 384GB | ~362GB | Intel | |
| nxv | 8 | 32 | 256GB | ~236GB | Intel | |
| sbg (ampere) | gpu | 2 | 48 | 384GB | ~362GB | Intel |
| sbg (ampere) | gpu, cluster=andrena | 16 | 48 | 384GB | ~362GB | Intel |
| sdv serial | 10 | 24 | 192GB | ~177GB | Intel | |
| sdv parallel | infiniband=sdv-ii | 15 | 24 | 192GB | ~177GB | Intel |
| srm | highmem | 1 | 48 | 1536GB | ~1483GB | Intel |
| panos1 | 1 | 32 | 512GB | ~491GB | Intel | |
| burst1 | 1 | 40 | 768GB | ~741GB | Intel | |
| Total | 122 | 5104 | 42.7TB |
Owned nodes complex
Users with access to owned nodes can ensure jobs run on an owned node by
requesting -l owned in the job script or on the command line e.g.
qlogin -l owned
The following table lists the CPU instruction sets supported by Apocrita Nodes. Note that AVX-512 is a family of extensions and an entry in this table may not mean that all AVX-512 extensions are supported on the node. To see whether a particular AVX-512 extension is supported you can check the CPU flags on a specific node.
| Node Type | SSE | SSE2 | SSSE3 | SSE4 | AVX | AVX2 | AVX-512 |
|---|---|---|---|---|---|---|---|
| ddy | |||||||
| emf | |||||||
| nxv | |||||||
| nxg | |||||||
| sdv | |||||||
| srm | |||||||
| sbg | |||||||
| sdx |
Hyperthreading is not enabled on compute nodes. Jobs are therefore allocated real cores.