Overview

Use the database instance navigator to review performance, resource consumption, active sessions, workload, query metrics, and system metrics for a selected database instance.

The Overview tab provides a high-level summary of the instance's performance, resource consumption, and active sessions over the selected time range.

Database instance navigator Overview tab showing performance cards, active sessions, total sessions, and wait types.

Performance and activity cards display aggregate metrics for the selected time range, along with a percentage that indicates the change compared to the previous equivalent time window.

  • Average Duration: Average execution time for queries on this instance and the percentage increase or decrease over the same time span as the selected time frame. For example, if you select a time frame of -2d, the metric is calculated starting from 2 days ago and the percentage increase or decrease is calculated from 4 days ago to 2 days ago.

  • Total Duration: Cumulative time the instance spent executing queries.

  • Total CPU time: Cumulative CPU resources consumed by the database engine.

  • Total Executions: Total number of queries executed.

  • Alerts: The count of active alerts for this instance, categorized by severity.

  • Average Active Sessions: Time series of active database sessions, sliced by wait types such as CPU, memory, network, lock contention, or I/O. Use this chart to see whether sessions are actively processing or waiting on resources. To expand the chart and view a detailed legend of wait states, select See all.

  • Connection information (Total sessions for Oracle Database, Total connections for Microsoft SQL Server, or Total threads for MySQL: Trend line of the total number of database connections, both active and inactive, over the selected time range. Use this chart to monitor connection spikes that might overwhelm the instance.

  • Wait Types: Donut chart that shows the percentage of sessions that spent time in each wait type in a given time range. Use this chart to identify the dominant bottleneck on the instance.

Tip: On the Average Active Sessions chart, drag-select a region and zoom in, toggle the visibility of wait types by selecting them in the legend, track CPU usage to detect resource bottlenecks, and track memory waiting to troubleshoot memory pressure.