# Beverin

Beverin is an AMD-based GPU cluster for the purpose of testing and porting applications.

## Cluster Specification

### Login node

Beverin has one [MI250X](<https://docs.cscs.ch/alps/hardware/index.md#amd-mi250x-gpu-nodes> "AMD MI250x GPU Nodes") login node.

### Compute Nodes

Beverin consists of 13 [MI250X](<https://docs.cscs.ch/alps/hardware/index.md#amd-mi250x-gpu-nodes> "AMD MI250x GPU Nodes") and 128 [MI300A](<https://docs.cscs.ch/alps/hardware/index.md#amd-mi300a-gpu-nodes> "AMD MI300A GPU Nodes") compute nodes.

| Node type | Memory | Nodes | CPU sockets | GPUs |
| --- | --- | --- | --- | --- |
| [mi200](<https://docs.cscs.ch/alps/hardware/index.md#amd-mi250x-gpu-nodes> "AMD MI250x GPU Nodes") | 512 GB | 13 | 13 | 104 |
| [mi300](<https://docs.cscs.ch/alps/hardware/index.md#amd-mi300a-gpu-nodes> "AMD MI300A GPU Nodes") | 512 GB | 128 | 512 | 512 |

See [Running jobs on Beverin](<https://docs.cscs.ch/clusters/beverin/index.md#running-jobs-on-beverin> "Running Jobs on Beverin") for details on the associated slurm partitions.

### Storage and file systems

Beverin uses the [HPCP filesystems and storage policies](<https://docs.cscs.ch/platforms/hpcp/index.md#file-systems-and-storage> "File systems and storage").

## Getting started

### Logging into Beverin

To connect to Beverin via SSH, first refer to the [ssh guide](<https://docs.cscs.ch/access/ssh/index.md#using-ssh> "Using SSH").

> [!NOTE]
>
> **`~/.ssh/config`**
>
> Add the following to your [SSH configuration](<https://docs.cscs.ch/access/ssh/index.md#adding-ela-as-a-jump-host-in-ssh-configuration> "Adding Ela as a jump host in SSH configuration") to enable you to directly connect to Beverin using `ssh beverin`.
>
> ```text
> Host beverin
>     HostName beverin.vc.cscs.ch
>     ProxyJump ela
>     User cscsusername
>     IdentityFile ~/.ssh/cscs-key
>     IdentitiesOnly yes
> ```

### Software

Beverin provides uenv to deliver programming environments and application software. Please refer to the [uenv documentation](<https://docs.cscs.ch/software/uenv/index.md#uenv>) for detailed information on how to use the uenv tools on the system.

- **Programming Environments**

  Provide compilers, MPI, Python, common libraries and tools used to build your own applications.

  - [prgenv-gnu](<https://docs.cscs.ch/software/prgenv/prgenv-gnu/index.md#prgenv-gnu>)
  - [linalg](<https://docs.cscs.ch/software/prgenv/linalg/index.md#linalg>)

In addition to the base `GNU` and `linalg` programming environments, a few other dedicated environments are provided on a best effort basis:

- **Climate and Weather Applications**

  Provide software stacks for climate and weather workflows on Beverin.

  - [ICON](<https://docs.cscs.ch/software/cw/icon/index.md#icon>)

- **Scientific Applications**

  Provide scientific applications.

  - [Quantumespresso](<https://docs.cscs.ch/software/sciapps/quantumespresso/index.md#quantum-espresso> "Quantum ESPRESSO")

- **Tools**

  Provide tools like

  - [Linaro Forge](<https://docs.cscs.ch/software/devtools/linaro-uenv/index.md#linaro-forge>)

See the [uenv quick start guide](<https://docs.cscs.ch/software/uenv/index.md#quick-start> "Quick start") to find all programming environments available on Beverin.

#### Containers

Beverin supports container workloads using the [Container Engine](<https://docs.cscs.ch/software/container-engine/index.md#container-engine>).

To build images, see the [guide to building container images on Alps](<https://docs.cscs.ch/build-install/containers/index.md#building-container-images-on-alps> "Building container images on Alps").

## Running Jobs on Beverin

### Slurm

Beverin uses [Slurm](<https://docs.cscs.ch/running/slurm/index.md#slurm>) as the workload manager, which is used to launch and monitor distributed workloads.

There are two Slurm partitions on the system, corresponding to the two node types:

- `mi200` (default)
- `mi300`

| Partition | Nodes | Max nodes/job | Default time | Max time |
| --- | --- | --- | --- | --- |
| `mi300` | 128 | unlimited | 01:00:00 | 1-00:00:00 |
| `mi200` (default) | 13 | unlimited | 01:00:00 | 1-00:00:00 |

The hardware available in each partition, including the [Slurm features](<https://docs.cscs.ch/running/slurm/index.md#slurm-features>) that can be selected with `--constraint`:

| Partition | Nodes | Node type | Features |
| --- | --- | --- | --- |
| `mi300` | 128 | [mi300](<https://docs.cscs.ch/alps/hardware/index.md#amd-mi300a-gpu-nodes> "AMD MI300A GPU Nodes") | [amdgpu](<https://docs.cscs.ch/clusters/beverin/index.md#gpu-partitioning-on-mi300a-nodes> "GPU partitioning on MI300A nodes") |
| `mi200` | 13 | [mi200](<https://docs.cscs.ch/alps/hardware/index.md#amd-mi250x-gpu-nodes> "AMD MI250x GPU Nodes") | none |

#### GPU partitioning on MI300A nodes

The GPU of each [MI300A APU](<https://docs.cscs.ch/alps/hardware/index.md#amd-mi300a-gpu-nodes> "AMD MI300A GPU Nodes") can be split into several logical GPUs, by grouping its six accelerator complex dies (XCDs). Select the mode with a [Slurm feature](<https://docs.cscs.ch/running/slurm/index.md#slurm-features> "Slurm features") on the `mi300` partition; jobs that do not select one run in SPX mode:

| Mode | Slurm constraint | GPUs per APU | XCDs per GPU | GPUs per node |
| --- | --- | --- | --- | --- |
| SPX (single partition) | `amdgpu_spx` (default) | 1 | 6 | 4 |
| TPX (triple partition) | `amdgpu_tpx` | 3 | 2 | 12 |
| CPX (core partitioned) | `amdgpu_cpx` | 6 | 1 | 24 |

run a job with each APU split into six GPUs

```bash
sbatch --partition=mi300 --constraint=amdgpu_cpx job.sh
```

The memory of the APU is not partitioned: every logical GPU can access all of it. SPX suits a single large workload per APU, while TPX and CPX allow several smaller workloads to share an APU, each on its own GPU. See the AMD documentation on [MI300A GPU partitioning](<https://instinct.docs.amd.com/projects/amdgpu-docs/en/latest/gpu-partitioning/mi300a/overview.html>) for details.

### FirecREST

Beverin can also be accessed using [FirecREST](<https://docs.cscs.ch/access/firecrest/index.md#firecrest>) at the `https://api.cscs.ch/ml/firecrest/v2` API endpoint.