Monitoring Top Sessions

On the Active Sessions Working page, the Top Working Sessions table displays the top sessions waiting for the corresponding wait class during the selected time period. Sessions represent specific user connections to the database through a user process.

A session lasts from the time a user logs in to the database until the user disconnects. For example, when a user starts SQL*Plus, the user must provide a valid database user name and password to establish a session. If a single session is consuming the majority of database activity, then you should investigate it.

To monitor the top working sessions: 

1. On the Performance page, in the Average Active Sessions chart, click the CPU Used block on the chart or its corresponding wait class in the legend.

   The Active Sessions Working page appears.

2. Under Detail for Selected 5 Minute Interval, select Top Sessions from the View list.

   The Top Working Sessions table appears.

3. In the Top Working Sessions table, click the Session ID link of the session consuming the most database activity.

   The Session Details page appears.

   This page contains information such as session activity, session statistics, open cursors, blocking sessions, wait events, and parallel SQL for the selected session.