Alain Raap

Antonio, maybe this feed can give some help:
https://moodle.org/mod/forum/discuss.php?d=362709

Hi, have you any caching installed on your server?
Redis is a good caching server that can speedup your
performance.

What’s the size of the database? If loaded in memory (InnoDB) you’ll need to have enough Memory on your server.

I see this error in your log "!!! Table "task_scheduled" does not exist !!!", there should be a table mdl_task_scheduled in your Moodle database. Can you check your table list in mysql ('show tables' in your database)? Did the automated backup task work? Were there made any backups?

Hi Antonio,

I hope this problem is already solved and that your automated backup runs ok now. I've had the same problem with another task in the Moodle cron that didn't work anymore and with debugging I got the same error. This error was caused by some Moodle cron php processes that hadn't finished and were freezed in state 'D'. After I had killed these processes the specific cron task that had failed was running without problem again. You can check your cron processes with 'ps -edafl | grep cron'. Every minute (the usual interval for Moodle cron) you can see the tasks that are running, usually with your user of the apache server. Another way to find problems with the Moodle cron tasks is to (temporary) log the output of your cron process in the Linux crontab to a file. Instead of using '> /dev/null' use '>> /var/log/moodle_cron.log'

Charlene, you say " I have no experience in Moodle Infrastructure." Do you have experience in Linux (+ Apache / MariaDB)? We have the same stack like your site but less concurrent users, for us it wasn't easy to get the stack working and tune it for a good performance. We have a large network and had a lot of security issues to tackle. I would ask assistance from your collegues from infrastructure to answer and define your questions. Is that possible?