The report collects data from two different sources depending on the time range you specify. If you provide time within the last one hour, the report is called "Real Time". If the time range is older than one hour, it is "Historical". The report content is slightly different for real-time and historical. The "Current ADDM Findings" tab is available only in real-time mode. See Figures 1 and 2.
Figure 1: Real-Time Performance Hub Report
Figure 2: Historical Performance Hub Report
In real-time mode, v$ views are used to retrieve the data. In historical mode, data is retrieved from Automatic Workload Repository (AWR). The data is organized in user-friendly tabs. The Activity tab is very useful - it shows the ASH analytics including activity by each SQLID. When you generate the report with level "ALL", you can drill down the SQL get more valuable information. Figure 3 shows the SQL Execution details with various tabs loaded with information and graphs. Figure 1 also shows the RAC tab. The RAC tab is available only if the database is RAC enabled.
Figure 3: SQL Execution Details Screen
Let me show you few screenshots of invoking the report. These screens give you a good idea of what options are available when running the report.
Figure 4: Invoking perfhub report.
Figure 5: Specify Database ID and Instance ID (press enter to take default values)
Figure 6: Start and End time formats for the report.
Note that the values can be specified in different formats.
Figure 7: Specifying time range and report name
To use the Performance Hub, need the Diagnostics Pack license. To view SQL Monitor data, need the Tuning Pack license as well.
Hope you find Performance Hub useful in diagnosing database problems.