How to Monitor a Channel Stage in the EPN

Managing the Event Processing Network 4-45 ■ Average Latency : The average amount of time it takes an event to pass through a specified path of the EPN, or latency. ■ Maximum Latency : The maximum amount of time it takes an event to pass through a specified path of the EPN. ■ Average Latency Threshold : Calculates the average latency values greater than the specified threshold value for specified start and end points. The Oracle CEP Visualizer monitoring feature is itself implemented as an Oracle CEP application; this means that the diagnostic information can be viewed as an event, and the application uses EPL rules to process these diagnostic events.

4.6.1 How to Monitor the Throughput and Latency of a Stage or Path in the EPN

You can monitor the throughput and latency of a stage or path in the EPN using the Oracle CEP Visualizer. To monitor the throughput and latency of a stage or path in the EPN: 1. In the left pane, navigate to and expand the Applications node of the Oracle CEP instance to which the application is deployed.

2. Select appname, where appname is the name of the application for which you

want to monitor throughput and latency.

3. Select the stage you wish to view and configure:

a. To use the EPN diagram:

– Click the Event Processing Network tab. – Double-click the stage you wish to monitor or the first stage in the path that you want to monitor.

b. To use the domain tree:

– Expand the appname Stages node, where appname is the name of the application you want to monitor. – Click the stage you wish to monitor or the first stage in the path that you want to monitor. – In the right pane, click the General tab The stage’s General tab appears. For example, Figure 4–48 shows the General tab for a channel. 4-46 Oracle Complex Event Processing Visualizer Users Guide Figure 4–48 General Tab for Channel Stage

4. Click the Create Diagnostics button.

A New Latency Profile accordion menu appears as shown in Figure 4–49 . It contains the following tabs: ■ Profile Information ■ Latency ■ Throughput

5. Click the Profile Information tab in the accordion menu as shown in

Figure 4–49 and enter the information that Table 4–5 lists.