Add GPU example

pages/merlin6/03-Slurm-General-Documentation/slurm-examples.md

@@ -157,6 +157,31 @@ srun $MYEXEC             # where $MYEXEC is a path to your binary file
 {{site.data.alerts.tip}} Also, always consider that **`'--mem-per-cpu' x '--cpus-per-task'`** can **never** exceed the maximum amount of memory per node (352000MB).
 {{site.data.alerts.end}}
 
+## GPU examples
+
+Using GPUs requires two major changes. First, the cluster needs to be specified
+to `gmerlin6`. This should also be added to later commands pertaining to the
+job, e.g. `scancel --cluster=gmerlin6 <jobid>`. Second, the number of GPUs
+should be specified using `--gpus`, `--gpus-per-task`, or similar parameters.
+Here's an example for a simple test job:
+
+```bash
+#!/bin/bash
+#SBATCH --partition=gpu         # Or 'gpu-short' for higher priority but 2-hour limit
+#SBATCH --cluster=gmerlin6      # Required for GPU
+#SBATCH --gpus=2                # Total number of GPUs
+#SBATCH --cpus-per-gpu=5        # Request CPU resources
+#SBATCH --time=1-00:00:00       # Define max time job will run
+#SBATCH --output=myscript.out   # Define your output file
+#SBATCH --error=myscript.err    # Define your error file
+
+module purge
+module load cuda                # load any needed modules here
+srun $MYEXEC                    # where $MYEXEC is a path to your binary file
+```
+
+Slurm will automatically set the gpu visibility (eg `$CUDA_VISIBLE_DEVICES`).
+
 ## Advanced examples
 
 ### Array Jobs: launching a large number of related jobs