Investigating Usability Connection Time Alarms in Foglight for Oracle Instances (4379441)

This article explains how to investigate Foglight Critical or Warning alarms triggered by high Usability Connection Time on Oracle database instances. This metric reflects the performance of a basic connectivity and query execution from an application perspective.

Collection Frequency

Foglight collects Usability Connection Time metrics at different intervals depending on system status:

Default Alarm Thresholds

These thresholds can be customized per environment. Foglight compares the average response time from the SELECT 1 FROM DUAL probe against these values.

What Is Usability Connection Time?

This metric measures the end-to-end time (in ms) between:

1. Query initiation: SELECT 1 FROM DUAL

2. Response received by application

This time includes:

• Network latency

• Listener responsiveness

• Authentication overhead

• Session allocation

• Basic SQL execution time

Normal range: 1–10 ms
Warning: > 10 ms
Critical: > 50 ms

How to view Usability Response Time History

Foglight UI Navigation

Configuration > Data > Databases > Oracle > Instance > [Select Instance] >  
Agent Name > Agent > Usability > Response > History

From this view, you can:

• Inspect raw metric data over time

• Identify peaks and trends

• Compare multiple instances

• Export data for reporting

Common Root Causes of High Connection Time

Recommended Investigation Steps

1). Run SQL Plus manually from the FglAM server with the query 

select 1 from dual;

2). Review the listener.log file for ORA-errors or timeouts

3). Use Foglight to review the CPU, memory, and I/O usage on the database host along with the active sessions count and blocking sessions