Sessions count data is not collected in the SQL Server Overview panel even though the Sessions are displayed in the agent panels.
The DBSS_SQL_Server_Connections_Summary is timing out in the agent log file.
The query executes in under a second directly on SQL Server, confirming no performance issue with the query itself.
Insufficient JVM Heap.
This collection times out because it is both heavier than others the agent runs and it runs in a low-priority pool, making it the first to be delayed when the FglAM is under memory or scheduling pressure.
When the heap is too small, the agent can experience frequent garbage collection and scheduling delays, which can prevent collections from executing in time, even when the SQL query itself is fast.
Increase the JVM heap on the Foglight Agent Manager to meet the sizing requirements detailed in the documentation.
