Currently, we set the default shutdown grace period to be 250ms. If however you fail to shut down cleanly in 250ms (maybe because the periodic task thread is busy, or gets descheduled), then you are at risk of crashing.

We offer the option to set a grace period so that users with more sophisticated needs about terminating the driver can take appropriate action. However, if you ignore the failed termination, as you easily will if you use the auto shutdown option, then you are likely to crash if your process begins orderly shutdown and starts destroying statics.

Instead, we should default to a 'wait forever' shutdown, and users can override if they need.