[GB25]: Disable core-dumps (#224)

Author: sekelle

docs/guides/gb25.md

@@ -39,7 +39,17 @@ The system [Daint][ref-cluster-daint] will be expanded to approximately 2350 Gra
 srun --uenv=prgenv-gnu/24.11:v2 --view=default -n? -N? ....
 ```
 
-## Tips
+## Recommendations on run configuration
+
+### Disabling core-dumps
+
+If a large job crashes and tries to write core-dump files on thousands of processes,
+it will overwhelm the filesystem. Therefore we strongly recommend to disable them with
+the following command:
+
+``` console title="disable writing of core-dump files"
+$ ulimit -S -c0
+```
 
 ### Improving job startup times