This tutorial illustrates use of a Global Stopping Strategy (GSS) in combination with the Service API. For background on the Service API, see the Service API Tutorial: https://ax.dev/tutorials/gpei_hartmann_service.html GSS is also supported in the Scheduler API, where it can be provided as part of SchedulerOptions. For more on Scheduler, see the Scheduler tutorial: https://ax.dev/tutorials/scheduler.html

Global Stopping stops an optimization loop when some data-based criteria are met which suggest that future trials will not be very helpful. For example, we might stop when there has been very little improvement in the last five trials. This is as opposed to trial-level early stopping, which monitors the results of expensive evaluations and terminates those that are unlikely to produce promising results, freeing resources to explore more promising configurations. For more on trial-level early stopping, see the tutorial: https://ax.dev/tutorials/early_stopping/early_stopping.html