Nextcloud 23.0.3 reaction time very slow sometimes

[Ti22Ja]

Generally, the response time of our cloud is good, but sometimes and increasingly often the response time increases into an abnormal range (well over 10,000ms).
Here is an example where you can see the normal and abnormal reaction time:

Currently, no 1:1 calls via Talk want to work either, then the Nextcloud does not respond at all. Currently there are about 30 users active at most.

Does anyone have an idea what this is due to?

In the log file I can only find the following recurring errors:

Box GET /well-known-handler/openid-configuration 404 Not Found No custom well-known config 1.976 ms - 71
Box GET /well-known-handler/openid-configuration 404 Not Found No custom well-known config 0.685 ms - 71

But the htaccess file (not .htaccess file!) already contains the following rules:

<IfModule mod_rewrite.c>
  RewriteEngine on
  RewriteCond %{HTTP_USER_AGENT} DavClnt
  RewriteRule ^$ /remote.php/webdav/ [L,R=302]
  RewriteRule .* - [env=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
  RewriteRule ^\.well-known/host-meta /public.php?service=host-meta [QSA,L]
  RewriteRule ^\.well-known/host-meta\.json /public.php?service=host-meta-json [QSA,L]
  RewriteRule ^\.well-known/webfinger /public.php?service=webfinger [QSA,L]
  RewriteRule ^\.well-known/nodeinfo /public.php?service=nodeinfo [QSA,L]
  RewriteRule ^\.well-known/carddav https://%{HTTP_HOST}/remote.php/dav/ [R=301,L]
  RewriteRule ^\.well-known/caldav https://%{HTTP_HOST}/remote.php/dav/ [R=301,L]
  RewriteRule ^remote/(.*) remote.php [QSA,L]
  RewriteRule ^(?:build|tests|config|lib|3rdparty|templates)/.* - [R=404,L]
  RewriteCond %{REQUEST_URI} !^/\.well-known/(acme-challenge|pki-validation)/.*
  RewriteRule ^(?:\.|autotest|occ|issue|indie|db_|console).* - [R=404,L]
</IfModule>

[Ti22Ja]

Still to the system used, since I forgot:
Ubuntu 20.04.2 LTS is installed.
RAM is theoretically maximum 32 GB and CPU 10 cores available and is not even remotely utilized by Nextcloud.

[nebulon]

Can you check, if this maybe relates to app updates or backups happening on the platform side? You can find those in the event log/activity listing in your Cloudron dashboard.

[Ti22Ja]

@nebulon
Just checked. Both backups and updates are only done at night between 11pm and 2am, as set by me. During the day there are no entries in the event log.

[fbartels]

@Ti22Ja is it maybe redis running out of memory and being restarted (continually)?

I had a slow nextcloud recently as well and increasing memory for the redis service through cloudron really helped.

[Ti22Ja]

@fbartels Thanks for the tip! I also had that as a first guess and have already increased the memory for redis a few weeks ago. Unfortunately, since then no improvement. Also I have increased the memory for mysql, unfortunately also without success.