Nextcloud version 19.01
Debian 9.13
Apache 2.4.25
PHP version 7.3
19.01 became available a few days ago for me. Since the upgrade I started getting memory issues where a large about of swap would be used but not main physical memory.
As this is a personal server and since it was still working I didn’t have time to look into it until today.
I have a Zabbix server monitor all my home devices. You can see everything is normal until the 14th.
Did you have the preview pre-generation already enabled in NC 18? Is someone uploading more images than usually? If not this could be a bug of this function…
If you disable this, the previews will be generated the first time you open the folder in the webinterface, so it will slow down the web interface…
Maybe your system is generating thumbnail previews from your images which would be a valid reason for heavy memory usage. You installed preview generator?
I did not have preview pre-generation consciously enabled in NC 18. The system has no other users than me. At most a few of pictures are uploaded each day from my phone.