Description:# nf-slurm-no-memory plugin
**Optimize CPU allocation for Slurm clusters with fixed memory-per-CPU policies.**
## Introductions
Some HPC clusters enforce a **fixed memory-per-CPU ratio** and do not allow users to explicitly set memory limits in Slurm job submissions (no --mem or --mem-per-cpu). This plugin dynamically calculates the **optimal CPU count** for each Nextflow process, ensuring efficient resource allocation while respecting cluster constraints.
- **Automatic CPU Calculation**: For each process, the plugin computes the required CPUs based on:
- The process's requested CPU count.
- The memory requirement divided by the cluster's **memory-per-CPU ratio** (default: **4 GB/CPU**).
- **Resource Efficiency**: Avoids under-allocation (job failures) or over-allocation (wasted resources).
## Installation
From Nextflow Plugin Registry
```bash
nextflow plugin install nf-slurm-no-memory
```
alternatively, you can reference the plugin in the pipeline config:
```
plugins {
id 'nf-slurm-no-memory'
}
```
From Source
1. Clone this repository:
```bash
git clone https://github.com/bioinfo-pf-curie/nf-slurm-no-memory.git
cd nf-slurm-no-memory
```
2. Build the plugin:
```bash
make assemble
```
3. Install the plugin:
```bash
make install
```
## Usage
Declare the plugin in your Nextflow pipeline configuration file:
```groovy title="nextflow.config"
plugins {
id "nf-slurm-no-memory@1.0.0"
}
```
Modify your `executor` to :
```groovy title="nextflow.config"
process {
executor = 'slurm-no-memory'
}
```
More details are available in the Nextflow [plugin documentation](https://www.nextflow.io/docs/latest/plugins.html#plugins) and the [configuration guide](https://www.nextflow.io/docs/latest/config.html).
## Params
The memory-per-CPU ratio can be adjusted via the memoryPerCpu variable in your configuration:
```groovy title="nextflow.config"
executor {
"slurm-no-memory" {
memoryPerCore = "8"
}
}
```
# Requirements
Nextflow 25.10.0 or later
Java 17 or later
# License
Licensed under Apache-2.0 license