Monitoring Performance Using the Performance Hub

The Performance Hub allows you to view all the performance data available for a specified time period. Once a time period is selected, the performance information is collected and presented based on performance subject areas.

This section includes the following topic:

Specifying the Time Period for Which to Display Statistics

When real-time data is selected, more granular data is presented (because data points are available every minute).

When historical data is selected, more detailed data (broken down by different metrics) is presented, but the data points are averaged out to the Automatic Workload Repository (AWR) interval (usually an hour).

Different tabs are available in the Performance Hub, depending on whether real-time or historical data is selected for the time period.

The following table describes the Performance Hub tabs, and indicates whether the tab is available when real-time data is selected or historical data is selected, or both.

Performance Hub Tab Name	Description	Available When
Summary	The Summary tab provides an overall view of the performance of the system for the specified time period. When real-time data for the last hour is displayed in the Performance Hub page, this tab shows a summary of running processes, memory allocation, database activity by category, and I/O data during the last hour. When historical data is displayed in the Performance Hub page, this tab shows a summary of average active session waits by category, load profile per second, active session activity, host CPU usage by the database instance and other processes, I/O read and write requests per second, and memory usage during the selected time period.	Real-time data or historical data is selected in the Select Time Period field
RAC	The RAC tab appears only when EM Express is being used with an Oracle RAC database (or cluster database). When real-time data is selected, this tab shows global cache activity information and a breakdown of activity (average active sessions) and resource usage (CPU, I/O, memory) per instance. When historical data is selected, this tab shows global cache activity information and a breakdown of activity (average active sessions) and resource usage (CPU, I/O, memory) per instance during the selected time period.	Real-time data or historical data is selected in the Select Time Period field
Activity	The Activity tab shows Active Session History (ASH) analytics. It allows detailed drilldown into average active sessions for ASH over the selected time period. This tab enables you to select an average active sessions dimension and view the top activity for that dimension for a selected time period. For example, you can view the SQL statements and user sessions that had the top average active sessions activity for the selected time period.	Real-time data or historical data is selected in the Select Time Period field
Workload	The workload profile charts show the pattern of user calls, parse calls, Redo Size and SQL*Net over the last 60 minutes in real-Time mode. The Sessions chart show the logon rate, current logons and open cursors. Clicking a SQL_ID displays the SQL Details page with more information about that SQL statement.	Real-time data or historical data is selected in the Select Time Period field
Monitored SQL	This tab enables you to view information about monitored SQL statements that were executing or that completed during the selected time period. The table displays information about monitored SQL statement executions. If there is a green spinning icon in the Status column, then the monitored statement did not complete during the selected time period. A red cross indicates that the SQL did not complete either due to an error or due to the session getting terminated. If there is a check mark in the Status column, then the statement completed its execution during the selected time period. SQL statements are monitored only if they have consumed at least 5 seconds of CPU or I/O time. You can view information such as the status of a statement, its duration, its type (SQL, PL/SQL, or DBOP), its SQL ID, its SQL plan hash, the user who issued it, whether it executed as a serial or parallel statement, the time the database spent performing CPU activity, I/O, or other activity for the statement, the read and write requests and bytes associated with the statement, and the start and end time for the statement. Click a SQL ID to display the SQL Details page with more information about that SQL statement.	Real-time data or historical data is selected in the Select Time Period field
ADDM	The ADDM tab enables you to view performance findings and recommendations that have been found by Automatic Database Diagnostics Monitor (ADDM) for tasks performed in the database during the selected time period. See "Performance Self-Diagnostics: Automatic Database Diagnostic Monitor " for more information about ADDM features.	Real-time data or historical data is selected in the Select Time Period field
Current ADDM Findings	The Current ADDM Findings tab enables you to view Real-time ADDM findings for the past five minutes. See "Performance Self-Diagnostics: Automatic Database Diagnostic Monitor " for more information about ADDM features.	Real-time data is selected in the Select Time Period field
Database Time	The Database Time tab enables you to view wait events by category for various metrics, and to view time statistics for various metrics for the selected time period.	Historical data is selected in the Select Time Period field
Resources	The Resources tab enables you to view operating system resource usage statistics, I/O resource usage statistics, and memory usage statistics for the selected time period.	Historical data is selected in the Select Time Period field
System Statistics	The System Statistics tab enables you to view database statistics by value, per transaction, or per second for the selected time period.	Historical data is selected in the Select Time Period field

The following figure shows the Performance Hub when Real Time - Last Hour data is selected.

Description of the illustration perf_hub_real_time.gif

The following figure shows the Performance Hub when historical data is selected.

Description of the illustration perf_hub_summary_hist.gif

To view Performance Hub data:

At the top of the Database Home page, from the Performance menu, select Performance Hub.

The Performance Hub page appears, with the Summary tab displayed. By default, real time data for the last hour appears in the Performance Hub.

You can select a different time period in the Select Time Period field if you would like to view historical data in the Performance Hub instead of real-time data.

In the figure above, Historical - All is selected in the Select Time Period field.
The time picker appears below the Select Time Period field.

The shaded block area in the time picker identifies the period of time for which performance statistics are currently being displayed in the Performance Hub. This is a subset of the period of time you selected in the Select Time Period field.

When historical data is displayed in the Performance Hub, you can increase or decrease the size of the shaded block area by clicking and dragging the user control on either end of the shaded block area.

The shaded block area is the time period for which statistics are displayed on all of the Performance Hub tabs, not just on the currently selected tab.
Click any of the tabs that appear in the Performance Hub to view the performance data on the tab.
Click the PerfHub Report button to generate a Performance Hub active report, which will include the contents of the Performance Hub tabs in an HTML file. After you click PerfHub Report, you are prompted to choose one of these report types for the Performance Hub active report:
- Basic: The basic information for all the tabs is saved in the report.
- Typical: All the information for the basic report is saved. Also, the SQL Monitor information for the top SQL in the Monitored SQL tab is saved, and ADDM reports are saved.
- All: All the information for the basic report is saved. Also, the SQL Monitor information for all of the SQL in the Monitored SQL tab is saved (not just for the top SQL), and all the detailed reports in all the tabs are saved.
You are then prompted for a location and file name for the active report, and the report is generated in that file and location. You use a web browser to view the report and navigate the Performance Hub tabs in the report.
When historical data is selected in the Performance Hub, you can click the AWR Report button to generate an AWR report for the selected time period.

You are prompted for a location and file name for the AWR report, and the report is generated in that file and location. You use a web browser to view the report.

See Also:

Oracle Database Performance Tuning Guide for more information about AWR