hi all, we have recently been hit by quite a few cases that triggered long waiters. we are aware of the excellent slides http://files.gpfsug.org/presentations/2017/NERSC/GPFS-Troubleshooting-Apr-2017.pdf but we are wondering if and how we can cause those waiters ourself, so we can train ourself in debugging and resolving them (either on test system or in controlled environment on the production clusters). all hints welcome. stijn