Since Plex background upgraded to 1.19.5.3035 database performance has been very poor. I run Plex under Ubuntu 18.04 with 4 VCPUS and 4GB of memory under ESX. System has been restarted since Plex was updated.
Up to now everything has been fine but since Plex updated things like scanning for new content in a library now runs for a lot longer with the server process sitting at 100% on one VCPU. Adding one file to a library with a couple of hundred existing files (and it being a library with no metadata) now takes 20+ mins rather than maybe 30 secs.
This is also affecting the loading of posters in the server web interface and occasional general timeouts on the server pages. This did not happen at all with the previous version.
Had another look at this again last night. The only messages it was logging was time out messages due to transactions taking to long. That and the main Plex process pegging an entire CPU core continually.
It looks like something went wrong with the background up date to this version from the previous one. I removed the package ready to try rolling back as suggested and then rebooted to give a clean state. Then I thought before trying the older version I’d try reinstalling the current version. That appeared to install cleanly and is running a lot better with reasonable performance and no process sitting there eating CPU.
Which version of ESXi are you running?
If by chance 7.0b, some servers have a big problem with it, overheating instantly at boot to 100 Celsius, making everything slow.