Advice on task settings - Stuck mod_quiz\task\update_overdue_attempts stopped...

Hi everyone,We had a critical issue in our Moodle 4.5 instance (OracleLinux,PostgreSQL, 2 app servers).A single taskmod_quiz\task\update_overdue_attemptsgot stuck, causing the entire cron system to stop (https://moodle.org/mod/forum/discuss.php?d=470324):The root cause seems related to “Access restrictions / Availability conditions” that got corrupted after a course restore. Thiscompletely froze our system(around 7,000 courses and 40,000 users) until we manually found and fixed it.What concerns me most is thatone blocked task can stop all cron jobs. Before addressing the possible bug, I’d like your advice on configuring task settings for large Moodle sites, as I’m also hoping it could help prevent similar issues in the future.Based on the docs (https://docs.moodle.org/405/en/Cron), what do you recommend for these values?cron_keepalive (default: 3 min)task_scheduled_concurrency_limit (default: 3)task_scheduled_max_runtime (default: 30 min)task_adhoc_concurrency_limit (default: 3)task_adhoc_max_runtime (default: 30 min)We only run course backups once per week (weekends), since they take over a day and we don’t want them interfering with daily activity (e.g. exams) and for the last 2 academic years (Moodle 4.1) we used to havetask_adhoc_concurrency_limit=6. For the past 15 years we never experienced nothing similar...If anyone has already tuned these parameters for large instances, I’d really appreciate if you could share your experience or recommendations. 🙏Thanks in advance!Best,susana