The Session Waits Analysis Dashboard

The Session Wait Analysis dashboard provides an overview of the current DRITA wait events for an Advanced Server session. For more information about DRITA wait events, please see the Postgres Plus Advanced Server Performance and Scalability Guide.

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Use parameters on the PEM Server Configurations dialog to specify the auto-refresh rate for the Alerts dashboard. To access the Server Configuration dialog, select Server Configuration… from the PEM web interface Management menu.

The Session Wait Analysis dashboard header displays the date and time that the server started, the date and time that the dashboard was last updated, and the number of alerts currently triggered for the specified database (and monitored objects that reside within that database).

The Session Waits Overview displays statistics gathered by the most recent execution of the PEM probe:

  • The Session Waits By Number Of Waits pie chart displays the 5 most frequently encountered wait events, per Advanced Server session. For more information about the events that can cause a wait event, see the EDB Postgres Advanced Server Guide.
  • The Session Waits By Time Waited pie chart displays the 5 wait events that consume the most time, per Advanced Server session. To gather and display data in the Session Time Waits by Time Waited pie chart, you must modify the postgresql.conf file for the monitored server, setting timed_statistics = on, and restart the server. Please note that this will cause server performance to degrade. For more information about using Advanced Server DRITA timers and the events that can cause a wait event, please see the EDB Postgres Advanced Server Guide.

The Session Waits Details table lists the current system wait events for the selected database. Click a column heading to sort the table by the column data; click again to reverse the sort order.The table displays:

  • The User column displays the name of the user that encountered the wait.
  • The Wait Name column displays the name of the of wait event.
  • The Wait Count column displays the total number of waits encountered by the user.
  • The Time (ms) displays the number of milliseconds that the user waited for the specified event.
  • The Wait Time (%) column displays the percentage of the total wait time consumed by the specified wait event.

To gather and display data in the Time (ms) and Wait Time (%) columns, you must modify the postgresql.conf file for the monitored server, setting timed_statistics = on, and restart the server. Please note that this will cause server performance to degrade. For more information about using Advanced Server DRITA timers, please see the EDB Postgres Advanced Server Guide.