Fail stale trials and run their failure callbacks.
The running trials whose heartbeat has not been updated for a long time will be failed, that is, those states will be changed to
study (Study) – Study holding the trials to check.
- Return type:
Added in v2.9.0 as an experimental feature. The interface may change in newer versions without prior notice. See https://github.com/optuna/optuna/releases/tag/v2.9.0.