Composability

COSMA has two composable systems to allow experimentation with composability, i.e. the ability to define server components within software.

Liqid system

A Liqid system installed in 2021 has 4 nodes (including a login node) to which both GPU and RAM can be composed upon demand (i.e. a request to cosma-support).

The GPUs are NVIDIA A100-40GB. There are 3 GPUs which can be configured between the nodes. To select a node containing a GPU, please add #SBATCH --constraint=gpu to your batch script. See the GPU page for more details.

To make use of the composed RAM, prefix your commands with mm. For example, free -h will show you there is 2TB RAM on the login8b node, while mm free -h gives access to the additional composed RAM, and so (depending on configuration) will usually show you that there is 4.5TB RAM available.

CerIO system

A CerIO system installed in 2024 has 8 nodes which share 8 GPUs, allowing servers with up to 8 GPUs to be configured. Follow the instructions to use this system.