kpesio--- via discuss <discuss@lists.mariadb.org> writes:
Documentation at https://mariadb.com/kb/en/automating-mariadb-tasks-with-events/ states: "The event scheduler runs as a single thread. If any event is supposed to start while another event is running, its execution will be skipped."
I have simulated events triggering at same time, running with delays to get all kinds of overlapping schedules, writing to same table from
Usually in event systems, this kind of condition refers to what happens when an event is set to schedule repeatedly (say once every second), and the duration of one event is longer than the repeat interval (say 1.5 seconds). In this case, the condition means that every second event will be skipped, since the prior event trigger _of that same event_ is still running.
the event and not missed a single one. The information_schema.events tables column last_executed has - depending on scheduled time - valid values and I can see in the processlist events running at same time.
I don't know the details of the MariaDB event scheduler, but it sounds like you were testing overlap of different events. You can try setting up a single repeatedly scheduled event that has duration longer than the repeat interval (eg. using SLEEP()), and then see if the different instances of such an event overlap or if they are skipped. Hope this helps, - Kristian.