Riki Otaki

Thank you for the comment! @keisuke-umezawa > * If the file stores a lot of studies e.g. 1000 but users just want to read one of studies, can we do...

[note] [c89613f](https://github.com/optuna/optuna/pull/3854/commits/c89613fd93f7613a95ffa88819c52286fbcb5ad9) # Bench 10000 trials using 10 processes ## Benchcode ```python3 from concurrent.futures import ProcessPoolExecutor import optuna from optuna import optuna from optuna.logging import set_verbosity, ERROR def objective(trial): x...

`Study._pop_waiting_trial_id()` should be thread-safe because it calls `storage.get_all_trials` and `storage.set_trial_state_values` sequentially. If more than two threads interleave when executing `Study._pop_waiting_trial_id()`, one of them might see a trial with a COMPLETED...