Nextcloud deployment in K8S really slow


I have installed a Nextcloud deployment in a minimal cluster of K8S (microk8s).

I have uploaded a lot of pictures, and it turns out really slow. I have found out it seems nextcloud creates a thumbnail on demand the first time a user accesses to the folder containing those photos, and it slow down the system and even it freezes it.

I have changed the generation of those thumbnails to ‘cron’ creation, but it’s nor working. And I cannot set up it up manually as I’m working with microk8s and I can’t access to the container with www-data user, which is the user being used to this.

Any suggestion?

I’m kind of frustrated…

So the php processes are run by which user? It is the same for the cronjobs, the famous www-data is just the default user in Debian/Ubuntu systems.
Also check out your logfiles, the cronjobs should leave a trace when they were run. The wrong user can be one reason, the other, the cronjob is a command-line command, meaning the php configuration can be slightly different from the one you are using with the web-browser and some modules might be missing.