We are working with ArcGIS Enterprise 11.3 in an environment with four servers (Portal, 2x ArcGIS Server, DataStore) running on Windows Server 2022. The data for our webservices is referenced from Enterprise-Geodatabases.
We have 415 webservices (324 shared intances, 85 dedicated instances, 6 hosted)
We are having issues with the shared instance services that are not behaving properly. Sometimes they take a long time to show up or disappear during usage.
In the logs I see a lot of the following error for many different webservices:
- CreateDynamicMapService failed for service "..."

Unfortunately, even when setting the log level to "Fine" there is not more information.
It seems that the DynamicMappingHost that is used to run the shared instance services has an issue, but I am not able to find out what the problem is. I have played around with the Shared Instance Settings, changed the values for javaHeapSize, SDEConnectionPoolSize for the DynamicMappingHost as well as the Web server maximum heap size for the ArcGIS Servers. I even adapted the non-interactive desktop heap size in the Windows registry, but nothing seems to affect this problem?
Has anybody come across something similar or has any additional ideas, where this could be coming from?