4 Managing the Event Processing Network

This chapter describes how you can use Oracle Event Processing Visualizer to manage the event processing networks (EPNs) of a deployed Oracle Event Processing application. It includes information on viewing the EPN graphically, recording and playing back event flow for debugging, tracing and injecting events, and monitoring channels and throughput.

This chapter includes the following sections:

• Section 4.1, "Viewing the EPN of an Application"

• Section 4.2, "Viewing and Editing the Configuration of a Stage"

• Section 4.3, "Recording and Playing Back Events in the EPN"

• Section 4.4, "Tracing and Injecting Events in the EPN"

• Section 4.5, "Monitoring a Channel Stage in the EPN"

• Section 4.6, "Monitoring the Throughput and Latency of a Stage or Path in the EPN"

For more information, see Section 3.1, "Event Processing Network (EPN) Management".

4.1 Viewing the EPN of an Application

Using the Oracle Event Processing Visualizer, you can view the EPN of a deployed application.

4.1.1 How to View the EPN of an Application

You can use the Oracle Event Processing Visualizer to view the EPN of a deployed application.

To view the EPN of an application:

1. In the left pane, navigate to and expand the Applications node of the Oracle Event Processing instance to which the application is deployed.

2. Select appname, where appname is the name of the application whose EPN you want to view.

3. In the right pane, click the Event Processing Network tab.

   The Event Processor Network panel is displayed as Figure 4-1 shows.

   Figure 4-1 Event Processing Network Panel

   
   Description of "Figure 4-1 Event Processing Network Panel"
   
   

   The name of a stage appears above the stage in black text. For example, there is an Oracle CQL processor called FindCrossRates and the name of its inbound channel is FxQuoteStream.

   The name of the event type transmitted on a given channel is shown below the connecting line in blue text. For example, the event type transmitted on the FxQuoteStream is CrossRateEvent.

4. To navigate to areas of the EPN that are off the screen, click in the miniature EPN view, and drag.

5. To change the layout of the EPN, select a layout option from the Layout menu:

   • organic

   • tree

   • hierarchic (default)

   • balloon

   • orthogonal

6. To change the way the EPN fits in the browser window:

   1. Click on the Zoom slider and drag to the right to increase the zoom level; drag left to decrease the zoom level.

   2. Click the Fit Content button to automatically adjust the zoom level to make all of the EPN visible in the browser window; click the Actual Size button to reset the zoom level to zero.

   3. Click the Zoom Out (+) button or Zoom In (-) button.

4.2 Viewing and Editing the Configuration of a Stage

Using Oracle Event Processing Visualizer, you can view the configuration of any stage and change the configuration for some stages.

Note:

Any changes to rules and Oracle high availability adapters are propagated to the other servers in the same group. That is, all rule and and Oracle high availability adapter configurations is automatically synchronized. Other configuration changes are not synchronized. For example, if you change record/playback or JMS adapter configuration on one server in a multi-server domain, then these changes are not synchronized with the other servers in the same group. For more information, see Chapter 18, "Managing Multi-Server Domains"

4.2.1 How to View and Edit the Configuration of a Stage

You can view and change the configuration of a stage using the Oracle Event Processing Visualizer.

To view and edit the configuration of a stage:

1. In the left pane, navigate to and expand the Applications node of the Oracle Event Processing instance to which the application is deployed.

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

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

   1. To use the EPN diagram:

      • Click the Event Processing Network tab.

      • Double-click the stage you wish to view or Right-click the stage and select Open Panel.

   2. To use the domain tree:

      • Expand the appname > Stages node, where appname is the name of the application you want to view.

      • Click the stage you wish to view.

      • In the right pane, click the General tab

   The stage's configuration appears.

   For example, Figure 4-2 shows the General tab for a channel.

   Figure 4-2 General Tab for Channel Stage: Before Clicking Edit

   
   Description of "Figure 4-2 General Tab for Channel Stage: Before Clicking Edit"
   
   

   Note:

   Not all stage's configuration can be updated by Oracle Event Processing Visualizer. An Edit button will appear if the configuration can be updated.

   For a description of the configuration properties for each possible stage, see:

   • Section 4.2.1.1, "Channel Properties"

   • Section 4.2.1.2, "Channel Properties: Outbound Channel"

   • Section 4.2.1.3, "Channel Properties: Outbound Channel With Query Selector"

   • Section 4.2.1.4, "Stream Properties"

   • Section 4.2.1.5, "Oracle CQL Processor Properties"

   • Section 4.2.1.6, "EPL Processor Properties"

   • Section 4.2.1.7, "Adapter Properties"

   • Section 4.2.1.8, "JMS Adapter Properties"

   • Section 4.2.1.9, "Oracle Event Processing High Availability Input Adapter Properties"

   • Section 4.2.1.10, "Oracle Event Processing High Availability Buffering Output Adapter Properties"

   • Section 4.2.1.11, "Oracle Event Processing High Availability Broadcast Output Adapter Properties"

   • Section 4.2.1.12, "Oracle Event Processing High Availability Correlating Output Adapter Properties"

   • Section 4.2.1.13, "Event Bean Properties"

   • Section 4.2.1.14, "POJO Properties"

   • Section 4.2.1.15, "Cache Properties: Oracle Coherence Cache"

   • Section 4.2.1.16, "Cache Properties: Oracle Event Processing Local Cache"

4. Click the Edit button, if present.

   Modifiable attributes become editable as Figure 4-3 shows.

   Figure 4-3 General Tab for Channel Stage: After Clicking Edit

   
   Description of "Figure 4-3 General Tab for Channel Stage: After Clicking Edit"
   
   

5. Enter new values for editable fields.

   For example, for the Max Size and Max Threads fields in Figure 4-3.

6. To commit your changes, click Save.

7. To leave the configuration unchanged, click Cancel.

4.2.1.1 Channel Properties

Figure 4-4 shows the General tab for a channel stage.

Figure 4-4 General Tab for Channel Stage

Description of "Figure 4-4 General Tab for Channel Stage"

After you click Edit, you can modify the attributes that are not shaded grey. Table 4-1 describes all the attributes on the General tab for this stage.

Table 4-1 General Tab Properties: Channel

Attribute	Description
Channel Type	Stream or Relation. For more information, see "Channels Representing Streams and Relations" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.
Max Size	Specifies the maximum size of the channel. Zero-size channels synchronously pass-through events. Non-zero size channels process events asynchronously, buffering events by the requested size. The default value is 1024.
Max Threads	Specifies the maximum number of threads that will be used to process events for this channel. You can change Max Threads from 0 to a positive integer (that is, from a pass-through to multiple threads) without redeploying. However, if you change Max Threads from a positive integer to 0 (that is, from multiple threads to a pass-through), then you must redeploy your application. If the Max Size attribute is 0, then setting a value for Max Threads has no effect. The default value for this attribute is 1.
Event Type Name	The name of the event type that this channel carries.
Timestamp Type	Use this element to specify whether or not the channel is application timestamped, that is, if the application is responsible for assigning a timestamp to each event, using any time domain. Valid values are: SYSTEM-TIME (default) APPLICATION-TIME For more information, see child element application-timestamped in "wlevs:channel" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.
Automatic HeartBeat	For system timestamped relations or streams, time is dependent upon the arrival of data on the relation or stream data source. Oracle Event Processing generates a heartbeat on a system timestamped relation or stream if there is no activity (no data arriving on the stream or relation's source) for more than this number of nanoseconds. Either the relation or stream is populated by its specified source or Oracle Event Processing generates a heartbeat every Automatic HeartBeat number of nanoseconds. Note: This attribute is only applicable when a non-streaming source is connected to the channel. For more information, see "heartbeat" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

For more information, see:

• "channel" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse

• Section 4.2.1.2, "Channel Properties: Outbound Channel"

• Section 4.2.1.3, "Channel Properties: Outbound Channel With Query Selector"

4.2.1.2 Channel Properties: Outbound Channel

Figure 4-5 shows the General tab for an outbound channel stage with an upstream Oracle CQL processor. The Channel Parameter accordion tab is selected.

Figure 4-5 General Tab Outbound Channel Parameters

Description of "Figure 4-5 General Tab Outbound Channel Parameters "

After you click Edit, you can modify the attributes that are not shaded grey. Table 4-2 describes all the attributes on the General tab for this stage.

Table 4-2 General Tab Properties: Outbound Channel

Attribute	Description
Channel Type	Stream or Relation. For more information, see "Channels Representing Streams and Relations" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.
Max Size	Specifies the maximum size of the channel. Zero-size channels synchronously pass-through events. Non-zero size channels process events asynchronously, buffering events by the requested size. The default value is 1024.
Max Threads	Specifies the maximum number of threads that will be used to process events for this channel. You can change Max Threads from 0 to a positive integer (that is, from a pass-through to multiple threads) without redeploying. However, if you change Max Threads from a positive integer to 0 (that is, from multiple threads to a pass-through), then you must redeploy your application. If the Max Size attribute is 0, then setting a value for Max Threads has no effect. The default value for this attribute is 1.
Event Type Name	The name of the event type that this channel carries.

For more information, see:

• "channel" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse

• Section 4.2.1.1, "Channel Properties"

• Section 4.2.1.3, "Channel Properties: Outbound Channel With Query Selector"

4.2.1.3 Channel Properties: Outbound Channel With Query Selector

Figure 4-6 shows the General tab for a channel stage with an upstream Oracle CQL processor. The Selectors accordion tab is selected.

Figure 4-6 General Tab Selectors for Outbound Channel Stage

Description of "Figure 4-6 General Tab Selectors for Outbound Channel Stage "

The Selector tab is only applicable if the up-stream node is an Oracle CQL processor.

After you click Edit, use the Selector tab, you can specify which up-stream Oracle CQL processor queries are permitted to output their results to the channel:

1. Select an up-stream Oracle CQL processor from the Processor pull-down menu.

   The available Oracle CQL rules associated with the selected processor are listed below the pull-down menu.

2. Use the left and right-pointing arrow buttons to move one or more rules to the Selected Queries list.

   Only rules in the Selected Queries list will output events to the channel.

Note:

You must add a query to the upstream Oracle CQL processor before you can add the query name to the channel selector. For more information, see Section 6.1.1, "How to Create a Rule in an Oracle CQL Processor Using the Query Wizard".

For more information, see:

• "Controlling Which Queries Output to a Downstream Channel" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse

• Section 4.2.1.1, "Channel Properties"

• Section 4.2.1.2, "Channel Properties: Outbound Channel"

4.2.1.4 Stream Properties

Figure 4-7 shows the General tab for a stream stage.

Figure 4-7 General Tab for Channel Stage

Description of "Figure 4-7 General Tab for Channel Stage"

After you click Edit, you can modify the attributes that are not shaded grey. Table 4-3 describes all the attributes on the General tab for this stage.

Table 4-3 General Tab Properties: Stream

Attribute	Description
Max Size	Specifies the maximum size of the stream. Zero-size streams synchronously pass-through events. Non-zero size streams process events asynchronously, buffering events by the requested size. The default value is 1024.
Max Threads	Specifies the maximum number of threads that will be used to process events for this stream. You can change Max Threads from 0 to a positive integer (that is, from a pass-through to multiple threads) without redeploying. However, if you change Max Threads from a positive integer to 0 (that is, from multiple threads to a pass-through), then you must redeploy your application. If the Max Size attribute is 0, then setting a value for Max Threads has no effect. The default value for this attribute is 1.

4.2.1.5 Oracle CQL Processor Properties

Table 4-3 shows the General tab for an Oracle CQL processor stage.

Figure 4-8 General Tab for Oracle CQL Processor Stage

Description of "Figure 4-8 General Tab for Oracle CQL Processor Stage"

There are no editable properties for this type of stage.

For more information, see "processor (Oracle CQL)" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

4.2.1.6 EPL Processor Properties

Figure 4-9 shows the General tab for an EPL processor stage.

Figure 4-9 General Tab for EPL Processor Stage

Description of "Figure 4-9 General Tab for EPL Processor Stage"

There are no editable properties for this type of stage.

For more information, see "processor (EPL)" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

4.2.1.7 Adapter Properties

Figure 4-10 shows the General tab for an adapter stage.

Figure 4-10 General Tab for an Adapter Stage

Description of "Figure 4-10 General Tab for an Adapter Stage"

There are no editable properties for this type of stage.

For more information, see "adapter" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

4.2.1.8 JMS Adapter Properties

Figure 4-16 shows the General tab for a JMS adapter.

Figure 4-11 General Tab for a JMS Adapter Stage

Description of "Figure 4-11 General Tab for a JMS Adapter Stage"

There are no editable properties for this type of stage.

For more information, see "adapter" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

4.2.1.9 Oracle Event Processing High Availability Input Adapter Properties

Figure 4-12 shows the General tab for an Oracle Event Processing high availability input adapter.

Figure 4-12 General Tab for an Oracle Event Processing High Availability Input Adapter Stage

Description of "Figure 4-12 General Tab for an Oracle Event Processing High Availability Input Adapter Stage"

There are no editable properties for this type of stage.

For more information, see "How to Configure the High Availability Input Adapter" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

4.2.1.10 Oracle Event Processing High Availability Buffering Output Adapter Properties

Figure 4-13 shows the General tab for an Oracle Event Processing high availability buffering output adapter.

Figure 4-13 General Tab for an Oracle Event Processing High Availability Buffering Output Adapter Stage

Description of "Figure 4-13 General Tab for an Oracle Event Processing High Availability Buffering Output Adapter Stage"

There are no editable properties for this type of stage.

For more information, see "How to Configure the Buffering Output Adapter" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

4.2.1.11 Oracle Event Processing High Availability Broadcast Output Adapter Properties

Figure 4-14 shows the General tab for an Oracle Event Processing high availability broadcast output adapter.

Figure 4-14 General Tab for an Oracle Event Processing High Availability Broadcast Output Adapter Stage

Description of "Figure 4-14 General Tab for an Oracle Event Processing High Availability Broadcast Output Adapter Stage"

There are no editable properties for this type of stage.

For more information, see "How to Configure the Broadcast Output Adapter" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

4.2.1.12 Oracle Event Processing High Availability Correlating Output Adapter Properties

Figure 4-15 shows the General tab for an Oracle Event Processing high availability correlating output adapter.

Figure 4-15 General Tab for an Oracle Event Processing High Availability Correlating Output Adapter Stage

Description of "Figure 4-15 General Tab for an Oracle Event Processing High Availability Correlating Output Adapter Stage"

There are no editable properties for this type of stage.

For more information, see "How to Configure the Correlating Output Adapter" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

4.2.1.13 Event Bean Properties

Figure 4-16 shows the General tab for an event bean stage.

Figure 4-16 General Tab for Event Bean Stage

Description of "Figure 4-16 General Tab for Event Bean Stage"

There are no editable properties for this type of stage.

For more information, see "event-bean" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

4.2.1.14 POJO Properties

Figure 4-17 shows the General tab for a Plain Old Java Object (POJO) stage.

Figure 4-17 General Tab for POJO Stage

Description of "Figure 4-17 General Tab for POJO Stage"

There are no editable properties for this type of stage.

4.2.1.15 Cache Properties: Oracle Coherence Cache

Figure 4-18 shows the properties for an Oracle Coherence Cache stage.

Figure 4-18 Oracle Coherence Cache Stage Properties

Description of "Figure 4-18 Oracle Coherence Cache Stage Properties"

There are no editable properties for this type of stage.

For more information, see:

• Section 18.2, "Managing Oracle Coherence"

• "coherence-cache-config" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse

4.2.1.16 Cache Properties: Oracle Event Processing Local Cache

Figure 4-19 shows the properties for an Oracle Event Processing Local Cache stage.

Figure 4-19 Oracle Event Processing Local Cache Stage Properties

Description of "Figure 4-19 Oracle Event Processing Local Cache Stage Properties"

After you click Edit, you can modify the attributes that are not shaded grey. Table 4-4 describes all the attributes on the General tab for this stage.

Table 4-4 Properties: Oracle Event Processing Local Cache

Attribute	Description
Max Size	Specifies the max-size element to define the number of cache elements in memory after which eviction or paging occurs. Currently, the maximum cache size is 2^31-1 entries. This element may be changed dynamically.
Idle Time	Specifies the number of milliseconds a cache entry may not be accessed before being actively removed from the cache. By default, there is no idle-time set. This element may be changed dynamically.
Write Policy	Specifies how Oracle Event Processing server writes information into the cache. Valid values are: WriteNone: Specifies no writes to a cache store. This is the default write policy. This element may be changed dynamically. For more information, see "write-none" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse WriteThrough: Specifies synchronous writes to the cache store. As soon as an entry is created or updated the write occurs. This element may be changed dynamically. For more information, see "write-through" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse. WriteBehind: Specifies asynchronous writes to the cache store. The cache store is invoked from a separate thread after a create or update of a cache entry. This element may be changed dynamically. For more information, see "write-behind" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.
Eviction Policy	Use this element to define the eviction policy the cache uses when Max Size is reached. Valid values are: FIFO: first in, first out. LRU: least recently used LFU: least frequently used (default) NRU: not recently used
Time To Live	Specifies the maximum amount of time, in milliseconds, that an entry is cached. Default value is 0 (which means infinite).

For more information, see "cache" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

4.3 Recording and Playing Back Events in the EPN

The event repository feature of Oracle Event Processing allows you to record events flowing through an event processing network (EPN) and store them so you can later play back the events. You configure the recording and playing back of events per stage, such as a processor or stream. Additionally, only events coming out of an event source can be recorded, and playback is possible only on event sinks (events are played back to the inbound side of the event sink stage.)

The only configuration options of record and playback that you can control using Oracle Event Processing Visualizer are event type, time, and speed.

For detailed information about how event and record playback works and how to configure a component, see "Configuring Event Record and Playback" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

For an example, see "Event Record and Playback Example" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

Alternatively, you can trace and inject events as Section 4.4, "Tracing and Injecting Events in the EPN" describes.

This section describes:

• Section 4.3.1, "How to Record Events"

• Section 4.3.2, "How to Playback Events"

4.3.1 How to Record Events

Using Oracle Event Processing Visualizer you can record events for a selected stage. Later, you can playback these events (see Section 4.3.2, "How to Playback Events").

To record events:

1. In the left pane, navigate to and expand the Applications node of the Oracle Event Processing instance to which the application is deployed.

2. Select appname, where appname is the name of the application you want to record and playback events with.

3. In the right pane, click the Event Processing Network tab.

   The Event Processor Network panel is displayed as Figure 4-20 shows.

   Figure 4-20 Event Processing Network Panel

   
   Description of "Figure 4-20 Event Processing Network Panel"
   
   

4. Select the stage for which you wish to record an event:

   1. To use the EPN diagram:

      • Right-click the stage for which you wish to record an event and select Record Event.

   2. To use the domain tree:

      • Expand the appname > Stages node, where appname is the name of the application you want to record and playback events with.

      • Click the stage for which you wish to record an event.

      • In the right pane, click the Record tab

   The Record panel appears as shown in Figure 4-21.

   Figure 4-21 The Record Tab

   
   Description of "Figure 4-21 The Record Tab"
   
   

   The Record tab in Oracle Event Processing Visualizer for a particular stage is divided into the following sections:

   • Recording Current Status: displays the current status of a recording. When the system has begun a recording session, then this field displays a blinking Recording message and it changes back to blank when the recording sessions ends. This section is read-only.

   • Recording Parameters: specifies the name of the database schema (Dataset name) and the provider information. You must pre-configure the provider for the event repository.

     For more information, see:

     • "Storing Events in the Persistent Event Store" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse

     • Chapter 17, "Managing the Persistent Event Store"

   • Event Type List: contains the Event Type List pane that displays the list of event types that are associated with a selected stage of the Oracle Event Processing application. Choose one or more events to record.

   • Record Schedule Entry: entries in this table displays the recording start time and end time for an event type. The fields in this table are disabled by default. Click Update Record to enable the fields in this table. The start and end time entries are optional fields, to start recording immediately, click the Start Recording button at the bottom of the panel.

   • Change Recording Schedule: allows you to change some of the properties of your existing recording entry. Certain properties, such as the event type, cannot be changed using Oracle Event Processing Visualizer. Use the calendar and clock controls to specify or change an existing start and end time for recording events.

5. Decide what you want to do:

   1. To add a new record schedule entry, click Add.

   2. To modify an existing record schedule entry, select the entry in the Record Schedule Entry table and click Edit.

   3. To delete an existing record schedule entry, select the entry in the Record Schedule Entry table and click Delete.

6. Configure the Recording Parameters:

   • DataSet Name: the value of the record-parameters child element dataset-name element from the simpleEventSource adapter application configuration file MIDDLEWARE_HOME\ocep_11.1\samples\domains\recplay_domain\defaultserver\applications\recplay\config.xml as Example 4-1 shows.

     Example 4-1 recplay Application Configuration File config.xml: adapter Element

     <adapter>
         <name>simpleEventSource</name>
         <record-parameters>
             <dataset-name>recplay_sample</dataset-name>
             <event-type-list>
                 <event-type>SimpleEvent</event-type>
             </event-type-list>
             <provider-name>test-rdbms-provider</provider-name>
             <batch-size>1</batch-size>
             <batch-time-out>10</batch-time-out>
         </record-parameters>
     </adapter>
     

   • Provider Name: the value of the rdbms-event-store-provider child element name which corresponds to the data-source child element name as Example 4-2 shows.

     When using the default Berkeley database provider, select default provider.

     Example 4-2 recplay Oracle Event Processing Server Configuration File config.xml: data-source and rdbms-event-store-provider Elements

     <data-source>
         <name>derby1</name>
         <connection-pool-params>
             <initial-capacity>15</initial-capacity>
             <max-capacity>50</max-capacity>
         </connection-pool-params>
         <driver-params>
             <url>jdbc:derby:dbtest1;create=true</url>
             <driver-name>org.apache.derby.jdbc.EmbeddedDriver</driver-name>
         </driver-params>
     </data-source>
     <rdbms-event-store-provider>
         <name>test-rdbms-provider</name>
         <data-source-name>derby1</data-source-name>
     </rdbms-event-store-provider>
     

     For more information, see Chapter 13, "Managing Data Sources".

7. Configure the Event type list:

   Use the left and right-pointing arrow buttons to move the events you want recorded from the Available event list to the Recorded event list.

   For more information, see Chapter 16, "Managing the Event Type Repository".

8. Decide when you want recording to start and end:

   1. If you want to schedule a record start and end time:

      • Click the calendar and clock controls to add a start time and end time.

      • Click Save.

        An alert dialog appears as Figure 4-22 shows.

        Figure 4-22 Record Schedule Confirmation Dialog

        
        Description of "Figure 4-22 Record Schedule Confirmation Dialog"
        
        

      • Click OK.

   2. If you want to record events immediately:

      • Click Save.

        An alert dialog appears as Figure 4-22 shows.

        Figure 4-23 Record Schedule Confirmation Dialog

        
        Description of "Figure 4-23 Record Schedule Confirmation Dialog"
        
        

      • Click OK.

      • Click Start.

   Oracle Event Processing Visualizer keeps track of whether a particular stage is currently recording or playing back events; based on this information, the Start and End buttons may be enabled or disabled as appropriate.

   When you start recording using Oracle Event Processing Visualizer, Oracle Event Processing uses the event type information from your record entry and begins recording immediately; the pre-scheduled time, if any, remains unchanged. Use the End button to stop recording of your session immediately.

9. Decide when you want to stop recording:

   1. If you scheduled a stop time, event recording will stop at that time.

   2. If you want to stop event recording immediately, click Stop.

4.3.2 How to Playback Events

Using Oracle Event Processing Visualizer you can playback previously recorded events (see Section 4.3.2, "How to Playback Events") for a selected stage.

To playback events:

1. In the left pane, navigate to and expand the Applications node of the Oracle Event Processing instance to which the application is deployed.

2. Select appname, where appname is the name of the application you want to record and playback events with.

3. In the right pane, click the Event Processing Network tab.

   The Event Processor Network panel is displayed as Figure 4-24 shows.

   Figure 4-24 Event Processing Network Panel

   
   Description of "Figure 4-24 Event Processing Network Panel"
   
   

4. Select the stage for which you wish to playback an event:

   1. To use the EPN diagram:

      • Right-click the stage for which you wish to playback an event and select Playback Event.

   2. To use the domain tree:

      • Expand the appname > Stages node, where appname is the name of the application you want to record and playback events with.

      • Click the stage for which you wish to playback an event.

      • In the right pane, click the Playback tab

   The Record panel appears as shown in Figure 4-25.

   Figure 4-25 The Playback Tab

   
   Description of "Figure 4-25 The Playback Tab"
   
   

   The Playback tab in Oracle Event Processing Visualizer for a particular stage is divided into the following sections:

   • Playback Current Status: displays the current status of playback. When the system has begun playing back a session, then this field displays a blinking Playback message and it changes back to blank when the playback session ends. This section is read-only.

   • Playback Parameters: specifies the name of the database schema (Dataset name) and the provider information. You must pre-configure the provider for the event repository.

     For more information, see:

     • "Storing Events in the Persistent Event Store" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse

     • Chapter 17, "Managing the Persistent Event Store"

   • Event Type List: contains the Event Type List pane that displays the list of event types that are associated with a selected stage of the Oracle Event Processing application. Choose one or more events to playback.

   • Playback Filter Entry: specify a set of filters using the clock and time controls, to run a playback for an event type in event type repository. Only events that were recorded during the start and end times you specify here will be played back.

   • Playback Schedule Entry: entries in this table displays the playback start time and end time for an event type. The fields in this table are disabled by default. Click Update Playback to enable the fields in this table. The start and end time entries are optional fields, to start recording immediately, click the Start Playback button at the bottom of the panel.

   • Change Playback Filter Parameters: allows you to change some of the properties of the selected playback filter entry.

   • Change Playback Schedule Parameters: allows you to change some of the properties of the selected playback schedule entry. Use the calendar and clock controls to specify or change an existing start and end time for playing back events.

5. Configure the Playback Parameters:

   • DataSet Name: the value of the record-parameters child element dataset-name element from the simpleEventSource adapter application configuration file MIDDLEWARE_HOME\ocep_11.1\samples\domains\recplay_domain\defaultserver\applications\recplay\config.xml as Example 4-3 shows.

     Example 4-3 recplay Application Configuration File config.xml: stream Element

     <stream>
         <name>eventStream</name>
         <playback-parameters>
             <dataset-name>recplay_sample</dataset-name>
             <event-type-list>
                 <event-type>SimpleEvent</event-type>
             </event-type-list>
             <provider-name>test-rdbms-provider</provider-name>
         </playback-parameters>
         <max-size>10000</max-size>
         <max-threads>2</max-threads>
     </stream> 
     

   • Provider Name: the value of the rdbms-event-store-provider child element name which corresponds to the data-source child element name as Example 4-4 shows.

     When using the default Berkeley database provider, select default provider.

     Example 4-4 recplay Oracle Event Processing Server Configuration File config.xml: data-source and rdbms-event-store-provider Elements

     <data-source>
         <name>derby1</name>
         <connection-pool-params>
             <initial-capacity>15</initial-capacity>
             <max-capacity>50</max-capacity>
         </connection-pool-params>
         <driver-params>
             <url>jdbc:derby:dbtest1;create=true</url>
             <driver-name>org.apache.derby.jdbc.EmbeddedDriver</driver-name>
         </driver-params>
     </data-source>
     <rdbms-event-store-provider>
         <name>test-rdbms-provider</name>
         <data-source-name>derby1</data-source-name>
     </rdbms-event-store-provider>
     

     For more information, see Chapter 13, "Managing Data Sources".

6. Configure the Event type list:

   Use the left and right-pointing arrow buttons to move the events you want played back from the Available event list to the Playback event list.

   For more information, see Chapter 16, "Managing the Event Type Repository".

7. Decide what you want to do:

   1. To add a new playback schedule entry, click Add.

   2. To modify an existing playback filter entry, select the entry in the Playback Filter Entry table and click Edit.

   3. To modify an existing playback schedule entry, select the entry in the Playback Schedule Entry table and click Edit.

   4. To delete an existing playback filter or schedule entry, select the entry in the appropriate table and click Delete.

8. Decide when you want playback to start and end:

   1. If you want to create a new playback filter entry:

      • Click the calendar and clock controls in the Change Playback Filter Parameters area to add a start time and end time.

      • Click Save.

        An alert dialog appears as Figure 4-26 shows.

        Figure 4-26 Playback Schedule Confirmation Dialog

        
        Description of "Figure 4-26 Playback Schedule Confirmation Dialog"
        
        

      • Click OK.

   2. If you want to create a new playback schedule entry:

      • Click the calendar and clock controls in the Change Playback Schedule Parameters area to add a start time and end time and to specify a speed and repeat mode.

        Speed: the default speed value is 1, which corresponds to normal speed. A value of 2 means that events will be played back 2 times faster than the original record speed. Similarly, a value of 0.5 means that events will be played back at half the speed.

        Repeat: set this to true to repeat playback until the scheduled end time or until you stop playback manually; set this to false to playback only once.

      • Click Save.

        An alert dialog appears as Figure 4-27 shows.

        Figure 4-27 Playback Schedule Confirmation Dialog

        
        Description of "Figure 4-27 Playback Schedule Confirmation Dialog"
        
        

      • Click OK.

   3. If you want to playback events immediately:

      • Click Save.

        An alert dialog appears as Figure 4-22 shows.

        Figure 4-28 Playback Schedule Confirmation Dialog

        
        Description of "Figure 4-28 Playback Schedule Confirmation Dialog"
        
        

      • Click OK.

      • Click Start.

   Oracle Event Processing Visualizer keeps track of whether a particular stage is currently recording or playing back events; based on this information, the Start and End buttons may be enabled or disabled as appropriate.

   When you start playback using Oracle Event Processing Visualizer, Oracle Event Processing uses the event type information from your playback entry and begins playback immediately; the pre-scheduled time, if any, remains unchanged. Use the End button to stop playback session immediately.

9. Decide when you want to stop playback:

   1. If you scheduled a stop time, event playback will stop at that time.

   2. If you want to stop event playback immediately, click Stop.

4.4 Tracing and Injecting Events in the EPN

Using the Event Inspector service and the stream visualizer, you can:

• Trace events on any HTTP pub-sub server channel.

• Trace events on any stage in the EPN on the Event Inspector service dynamic HTTP pub-sub server channel.

• Inject events to any HTTP pub-sub server channel

• Inject events into any stage in the EPN using the Event Inspector service dynamic HTTP pub-sub server channel.

Note:

The Event Inspector service is not for use on a production Oracle Event Processing server. It is for use only during development.

This section describes:

• Section 4.4.1, "How to Trace Events on a Dynamic Channel"

• Section 4.4.2, "How to Inject a Simple Event on an Event Inspector Service Dynamic Channel"

• Section 4.4.3, "How to Inject an Event as a JSON String on an Event Inspector Service Dynamic Channel"

For more information, see:

• Chapter 15, "Managing the Event Inspector Service"

• Chapter 14, "Managing HTTP Publish-Subscribe Servers"

• Section 4.5, "Monitoring a Channel Stage in the EPN"

• "Testing Applications With the Event Inspector" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse

Alternatively, you can record and playback events as Section 4.3, "Recording and Playing Back Events in the EPN" describes.

4.4.1 How to Trace Events on a Dynamic Channel

You can use Oracle Event Processing Visualizer to view the messages that are currently being published to a static channel.

For more information, see Section 9.5, "HTTP Publish-Subscribe Server Management".

To trace events on a dynamic channel:

1. Optionally, configure the HTTP pub-sub server to use to trace events.

   See Chapter 15, "Managing the Event Inspector Service".

2. In the left pane, navigate to and expand the Applications node of the Oracle Event Processing instance to which the application is deployed.

3. Select appname, where appname is the name of the application in which you want to trace and inject events.

4. In the right pane, click the Event Processing Network tab.

   The Event Processor Network panel is displayed as Figure 4-24 shows.

   Figure 4-29 Event Processing Network Panel

   
   Description of "Figure 4-29 Event Processing Network Panel"
   
   

5. Select the stage for which you wish to trace events:

   1. To use the EPN diagram:

      • Right-click the stage for which you wish to trace events and select Trace Event.

   2. To use the domain tree:

      • Expand the appname > Stages node, where appname is the name of the application in which you want to trace events.

      • Click the stage for which you wish to trace an event.

      • In the right pane, click the Trace Event tab

   The Trace Event panel appears as shown in Figure 4-30.

   Figure 4-30 The Trace Event Tab: Start

   
   Description of "Figure 4-30 The Trace Event Tab: Start"
   
   

6. Click Start.

   An alert dialog appears as Figure 4-31 shows.

   Figure 4-31 Trace Event Confirmation Dialog

   
   Description of "Figure 4-31 Trace Event Confirmation Dialog"
   
   

7. Click OK.

   The Status field reads ON.

   The Channel Name field shows the dynamic channel on which events passing through this stage are written. The Event Inspector service HTTP pub-sub channel is named:

   /SERVERNAME/APPLICATIONNAME/STAGENAME/output
   

   Where:

   • SERVERNAME: the name of the Oracle Event Processing server on which the application and stage you want to trace are executing.

   • APPLICATIONNAME: the name of the Oracle Event Processing application that owns the stage you want to trace.

   • STAGENAME: the name of the Oracle Event Processing application stage you want to trace.

   For example: /NonClusteredServer/cql/orderCSVAdapter/output.

8. In the top pane, click ViewStream.

   The Stream Visualizer panel appears as Figure 4-32 shows.

   Figure 4-32 Stream Visualizer (ViewStream): Subscribe

   
   Description of "Figure 4-32 Stream Visualizer (ViewStream): Subscribe"
   
   

9. In the PubSub Server Name pull down menu, select the name of the HTTP pub-sub server to use to trace events.

10. Click Initialize Client.

11. Select the Subscribe tab.

12. Click Refresh.

    The Subscribe tab is refreshed to show the dynamic channel for your stage.

13. Click the radio button next to the name of the channel to which the Oracle Event Processing server is publishing messages.

    For example: /NonClusteredServer/cql/orderCSVAdapter/output.

14. Click Subscribe.

    The Output messages received from subscription text box displays events being published to the channel.

    Note:

    If the Oracle Event Processing Visualizer fails to subscribe to the channel and displays an error in the Debug Messages area such as:

    14:25:54 GMT-0400: httpFaultHandler(): [RPC Fault faultString="Error #2096" faultCode="InvokeFailed" faultDetail="null"]
    

    Then, confirm the following:

    • Have you met the Oracle Event Processing Visualizer Adobe Flash and browser prerequisites? See Section 2.1.1, "Prerequisites".

15. To clear the Output messages received from subscription text, click Clear Text.

16. To unsubscribe from the channel, click Unsubscribe.

17. To stop event trace, select the stage you configured to trace events:

    1. To use the EPN diagram:

       • Right-click the stage for which you wish to trace an event and select Trace Event.

    2. To use the domain tree:

       • Expand the appname > Stages node, where appname is the name of the application in which you want to trace and inject events.

       • Click the stage for which you wish to trace an event.

       • In the right pane, click the Trace Event tab

    The Trace Event panel appears as shown in Figure 4-30.

    Figure 4-33 The Trace Event Tab: Stop

    
    Description of "Figure 4-33 The Trace Event Tab: Stop"
    
    

18. Click Stop.

    An alert dialog appears as Figure 4-34 shows.

    Figure 4-34 Trace Event Stop Confirmation Dialog

    
    Description of "Figure 4-34 Trace Event Stop Confirmation Dialog"
    
    

19. Click OK.

    The Status field reads OFF.

    The Channel Name field is blank.

4.4.2 How to Inject a Simple Event on an Event Inspector Service Dynamic Channel

You can inject a single, simple event by type into any stage in the EPN using the Event Inspector service dynamic channel.

The Oracle Event Processing Visualizer only supports simple event types whose properties are all simple Java types without nested Java objects. Event properties must be restricted to the following types:

• primitive Java types

• Java array or collection with simple Java type values

• Date

• BigDecimal

• BigInteger

Alternatively, you can inject an event with more complex properties by specifying the event as a JSON message. For more information, see Section 4.4.3, "How to Inject an Event as a JSON String on an Event Inspector Service Dynamic Channel".

Note:

The Event Inspector service is not for use on a production Oracle Event Processing server. It is for use only during development.

To inject a simple event on an Event Inspector service dynamic channel:

1. Optionally, configure the HTTP pub-sub server to use to trace events.

   See Chapter 15, "Managing the Event Inspector Service".

2. In the left pane, navigate to and expand the Applications node of the Oracle Event Processing instance to which the application is deployed.

3. Select appname, where appname is the name of the application in which you want to trace and inject events.

4. In the right pane, click the Event Processing Network tab.

   The Event Processor Network panel is displayed as Figure 4-24 shows.

   Figure 4-35 Event Processing Network Panel

   
   Description of "Figure 4-35 Event Processing Network Panel"
   
   

5. Select the stage for which you wish to inject events:

   1. To use the EPN diagram:

      • Right-click the stage for which you wish to inject an event and select Inject Event.

   2. To use the domain tree:

      • Expand the appname > Stages node, where appname is the name of the application in which you want to trace and inject events.

      • Click the stage for which you wish to inject an event.

      • In the right pane, click the Inject Event tab

   The Inject Event panel appears as shown in Figure 4-30.

   Figure 4-36 The Inject Event Tab: Start

   
   Description of "Figure 4-36 The Inject Event Tab: Start"
   
   

6. Click Start.

   An alert dialog appears as Figure 4-31 shows.

   Figure 4-37 Inject Event Start Confirmation Dialog

   
   Description of "Figure 4-37 Inject Event Start Confirmation Dialog"
   
   

7. Click OK.

   The Status field reads ON.

   The Channel Name field shows the dynamic channel on which events passing through this stage are injected. The Event Inspector service HTTP pub-sub channel is named:

   /SERVERNAME/APPLICATIONNAME/STAGENAME/input
   

   Where:

   • SERVERNAME: the name of the Oracle Event Processing server on which the application and stage you want to trace are executing.

   • APPLICATIONNAME: the name of the Oracle Event Processing application that owns the stage you want to trace.

   • STAGENAME: the name of the Oracle Event Processing application stage you want to trace.

   For example: /NonClusteredServer/cql/orderCSVAdapter/input.

8. In the top pane, click ViewStream.

   The Stream Visualizer panel appears as Figure 4-38 shows.

   Figure 4-38 Stream Visualizer (ViewStream): Publishing Simple Events

   
   Description of "Figure 4-38 Stream Visualizer (ViewStream): Publishing Simple Events"
   
   

9. In the PubSub Server Name pull down menu, select the name of the HTTP pub-sub server to use to trace events.

10. Click Initialize Client.

11. Select the Publish tab.

12. Click Refresh.

    The Publish tab is refreshed to show the dynamic channel for your stage.

13. Click the radio button next to the name of the channel to which the Oracle Event Processing server will inject messages.

    For example: /NonClusteredServer/cql/orderCSVAdapter/output.

14. From the Input Method radio button group, select Form Based Event.

15. From the Event Type pull down menu, select an event type.

    The View Stream panel updates to list the attributes of the event type you select.

    For example, Figure 4-38 shows the attributes for the DataStockTick event, which include:

    • Price

    • Symbol

    • PercChange

    • Volume

    • LastPrice

    Note:

    The View Stream Event Type pull down menu lists all the events defined in the event type repository that meet the restrictions that Section 4.4.2, "How to Inject a Simple Event on an Event Inspector Service Dynamic Channel" describes. To inject a more complex events, see Section 4.4.3, "How to Inject an Event as a JSON String on an Event Inspector Service Dynamic Channel".

16. Configure the attributes for the event type you selected.

    Hover your mouse over an attribute field to display a tool tip that indicates the data type for the attribute.

17. Click Publish.

    Oracle Event Processing Visualizer publishes the event on the Event Inspector service dynamic channel and it is received and processed by the stage that the channel identifies.

18. To stop event injection, select the stage you configured for event injection:

    1. To use the EPN diagram:

       • Right-click the stage for which you wish to inject an event and select Inject Event.

    2. To use the domain tree:

       • Expand the appname > Stages node, where appname is the name of the application in which you want to trace and inject events.

       • Click the stage for which you wish to inject an event.

       • In the right pane, click the Inject Event tab

    The Inject Event panel appears as shown in Figure 4-39.

    Figure 4-39 The Inject Event Tab: Stop

    
    Description of "Figure 4-39 The Inject Event Tab: Stop"
    
    

19. Click Stop.

    An alert dialog appears as Figure 4-31 shows.

    Figure 4-40 Inject Event Stop Confirmation Dialog

    
    Description of "Figure 4-40 Inject Event Stop Confirmation Dialog"
    
    

20. Click OK.

    The Status field reads OFF.

    The Channel Name field is blank.

4.4.3 How to Inject an Event as a JSON String on an Event Inspector Service Dynamic Channel

You can inject a single event directly to the HTTP pub-sub channel as a JSON-formatted character string.

You can use any event property that JSON can represent.

For details on the Event Inspector service JSON event structure and mandatory attributes, see "Event Inspector Event Types" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

Alternatively, you can inject a simple, pre-existing event. For more information, see Section 4.4.2, "How to Inject a Simple Event on an Event Inspector Service Dynamic Channel".

Note:

The Event Inspector service is not for use on a production Oracle Event Processing server. It is for use only during development.

To inject an event as a JSON string on an Event Inspector service dynamic channel:

1. Optionally, configure the HTTP pub-sub server to use to trace events.

   See Chapter 15, "Managing the Event Inspector Service".

2. In the left pane, navigate to and expand the Applications node of the Oracle Event Processing instance to which the application is deployed.

3. Select appname, where appname is the name of the application in which you want to trace and inject events.

4. In the right pane, click the Event Processing Network tab.

   The Event Processor Network panel is displayed as Figure 4-24 shows.

   Figure 4-41 Event Processing Network Panel

   
   Description of "Figure 4-41 Event Processing Network Panel"
   
   

5. Select the stage for which you wish to inject events:

   1. To use the EPN diagram:

      • Right-click the stage for which you wish to inject an event and select Inject Event.

   2. To use the domain tree:

      • Expand the appname > Stages node, where appname is the name of the application in which you want to trace and inject events.

      • Click the stage for which you wish to inject an event.

      • In the right pane, click the Inject Event tab

   The Inject Event panel appears as shown in Figure 4-30.

   Figure 4-42 The Inject Event Tab: Start

   
   Description of "Figure 4-42 The Inject Event Tab: Start"
   
   

6. Click Start.

   An alert dialog appears as Figure 4-31 shows.

   Figure 4-43 Inject Event Start Confirmation Dialog

   
   Description of "Figure 4-43 Inject Event Start Confirmation Dialog"
   
   

7. Click OK.

   The Status field reads ON.

   The Channel Name field shows the dynamic channel on which events passing through this stage are injected. The Event Inspector service HTTP pub-sub channel is named:

   /SERVERNAME/APPLICATIONNAME/STAGENAME/input
   

   Where:

   • SERVERNAME: the name of the Oracle Event Processing server on which the application and stage you want to trace are executing.

   • APPLICATIONNAME: the name of the Oracle Event Processing application that owns the stage you want to trace.

   • STAGENAME: the name of the Oracle Event Processing application stage you want to trace.

   For example: /NonClusteredServer/cql/orderCSVAdapter/input.

8. In the top pane, click ViewStream.

   The Stream Visualizer panel appears as Figure 4-44 shows.

   Figure 4-44 Stream Visualizer (ViewStream): Publishing JSON Events

   
   Description of "Figure 4-44 Stream Visualizer (ViewStream): Publishing JSON Events"
   
   

9. In the PubSub Server Name pull down menu, select the name of the HTTP pub-sub server to use to trace events.

10. Click Initialize Client.

11. Select the Publish tab.

12. Click Refresh.

    The Publish tab is refreshed to show the dynamic channel for your stage.

13. Click the radio button next to the name of the channel to which the Oracle Event Processing server will inject messages.

    For example: /NonClusteredServer/cql/orderCSVAdapter/output.

14. From the Input Method radio button group, select Json String.

15. Enter a JSON-formatted string in the text field as Example 4-5 shows.

    Example 4-5 JSON-Formatted Event String

    {
        "event-type": "myEventType",
        "operation": "insert",
        "binding": "outbound",
        "value":{
            "firstname": "Jane",
            "lastname": "Doe",
            "phone": {
                "code": 12345,
                "number": "office"
            },
        }
    }
    

    For complete details on the Event Inspector service JSON event structure and mandatory attributes, see "Event Inspector Event Types" in the Oracle Fusion Middleware Developer's Guide for Oracle Event Processing for Eclipse.

16. Click Publish.

    Oracle Event Processing Visualizer publishes the event on the Event Inspector service dynamic channel and it is received and processed by the stage that the channel identifies.

17. To stop event injection, select the stage you configured for event injection:

    1. To use the EPN diagram:

       • Right-click the stage for which you wish to inject an event and select Inject Event.

    2. To use the domain tree:

       • Expand the appname > Stages node, where appname is the name of the application in which you want to trace and inject events.

       • Click the stage for which you wish to inject an event.

       • In the right pane, click the Inject Event tab

    The Inject Event panel appears as shown in Figure 4-39.

    Figure 4-45 The Inject Event Tab: Stop

    
    Description of "Figure 4-45 The Inject Event Tab: Stop"
    
    

18. Click Stop.

    An alert dialog appears as Figure 4-31 shows.

    Figure 4-46 Inject Event Stop Confirmation Dialog

    
    Description of "Figure 4-46 Inject Event Stop Confirmation Dialog"
    
    

19. Click OK.

    The Status field reads OFF.

    The Channel Name field is blank.

4.5 Monitoring a Channel Stage in the EPN

You can use Oracle Event Processing Visualizer to monitor any channel stage (stream) of the event processing network (EPN) of an application.

Oracle Event Processing defines the following metrics that you can monitor for each channel:

• size: the number of events in the channel's queue.

4.5.1 How to Monitor a Channel Stage in the EPN

You can monitor a channel stage in the EPN using the Oracle Event Processing Visualizer.

To monitor a channel in the EPN:

1. In the left pane, navigate to and expand the Applications node of the Oracle Event Processing instance to which the application is deployed.

2. Select appname, where appname is the name of the application you want to monitor.

3. In the right pane, click the Channel Monitor tab.

   The Channel Monitor tab appears as Figure 4-47 shows.

   Figure 4-47 Channel Monitor Tab

   
   Description of "Figure 4-47 Channel Monitor Tab"
   
   

4. To monitor a channel, click on a channel in the All Channels list and drag and drop it onto one of the four graphs in the Channel Monitor tab.

   The channel name is added to a color-coded legend below the graph. The color corresponds to the channel's line in the graph.

   The channel name is also added to the Monitored Channels list.

   You can display all channels on one graph or distribute channels amongst the four graphs in any combination.

5. To change the scale of the graphs, click on the slider to the left of the vertical axis and drag it up or down.

6. To stop monitoring a channel, click the Remove button associated with it in the Monitored Channels list.

4.6 Monitoring the Throughput and Latency of a Stage or Path in the EPN

You can use Oracle Event Processing Visualizer to monitor the entry and exit points of a stage, or a specified path, of the event processing network (EPN) of an application. Oracle Event Processing defines the following metrics that you can monitor for each stage or path:

• Throughput: The number of events processed by the stage.

• 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 Event Processing Visualizer monitoring feature is itself implemented as an Oracle Event Processing 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 Event Processing 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 Event Processing 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:

   1. 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.

   2. 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.

   Figure 4-48 General Tab for Channel Stage

   
   Description of "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.

   Figure 4-49 New Latency Profile Screen - Profile Information Tab

   
   Description of "Figure 4-49 New Latency Profile Screen - Profile Information Tab"
   
   

   Table 4-5 Profile Information Attributes

   Attribute	Description
   Profile Name	The name of the diagnostic profile that you want to create.
   State	Select On if you want to enable the profile for immediate use. Select Off if you do not want to enable the profile for immediate use.

   
   

6. Click the Latency tab in the accordion menu as shown in Figure 4-50 and enter the information that Table 4-6 lists.

   Figure 4-50 New Latency Profile Screen - Latency Tab

   
   Description of "Figure 4-50 New Latency Profile Screen - Latency Tab"
   
   

   Table 4-6 Latency Attributes

   Attribute	Description
   Max Latency Metric	Specifies that you want to monitor the maximum amount of time it takes for events to flow through a stage or a subset of the event processing network (path).
   Average Latency Metric	Specifies that you want to monitor the average amount of time it takes for events to flow through a stage or a subset of the event processing network (path)
   Average Collection Interval	Specifies the time interval for which you want to gather diagnostic data. In other words, the sliding window across which the Average Latency Metric is computed. This value is enabled only if you specify Max Latency Metric.
   Threshold	Specify a value if you are interested in only receiving latency metrics that exceed a certain value. For example, if you would like to know when the latency exceeds 250 ms, specify a Threshold value of 250 ms. This value is enabled only if you specify Average Latency Metric.
   Start Stage Name	Specifies the name that you have provided for the start stage. If you want to monitor just the current stage, rather than a path in the EPN, then set the Start Stage Name and End Stage Name to the name of the current stage. Select Entry for the Start Stage Name option and Exit for the End Stage Name.
   End Stage Name	Specifies the name that you have provided for the end stage. If you want to monitor a path in the EPN, Oracle Event Processing Visualizer assumes that the current stage is the start of the path, and thus automatically selects it for the Start Stage Name field. Specify whether the start of the path should be the Entry or Exit of the current stage. Then, select the End Stage Name, or the end of the path you want to monitor, and specify whether the end of the path should be the Entry or Exit of the stage

   
   

7. Click the Latency tab in the accordion menu as shown in Figure 4-50 and enter the information that Table 4-6 lists.

   Figure 4-51 New Latency Profile Screen - Throughput Tab

   
   Description of "Figure 4-51 New Latency Profile Screen - Throughput Tab"
   
   

   Table 4-7 Throughput Attributes

   Attribute	Description
   Average Throughput Metric	Specifies that you want to monitor the average throughput of events flowing through the stage.
   Stage Name	Specify whether you want to monitor the throughput at the entry or exit of the stage
   Throughput Interval	Specifies the period of time for which the throughput is calculated. For example, if you specify a Throughput Interval of 1 second, the number of events passing through the stage in 1 second will be calculated. This will be averaged over the Average Interval you specify. Specify the time unit as Second, Millisecond, or Microsecond.
   Average Interval	Specifies the interval for gathering the average throughput. For example, if you specify a Throughput Interval of 1 second, the number of events passing through the stage in 1 second will be calculated. This will be averaged over the Average Interval you specify. Specify the time unit as Second, Millisecond, or Microsecond.

   
   

8. Click Save.

   A pop-up confirmation dialog appears in the lower-right corner of the panel.

   The saved diagnostic profile appears in the left domain tree, under the stage from which you created it, as shown in Figure 4-52.

   Figure 4-52 Left Domain Tree - Mydiagprofile

   
   Description of "Figure 4-52 Left Domain Tree - Mydiagprofile"
   
   

   Note:

   You can now restart a server or undeploy an application without losing the diagnostic profile you created.

9. Click OK.

10. Add the diagnostic profile to the Oracle Event Processing Visualizer Dashboard:

    1. Select the diagnostic profile in the left domain tree and click the Add to Dashboard button.

    2. Click the Dashboard link at the top of Oracle Event Processing Visualizer and drag and drop the diagnostic profile you created from the domain tree in the left pane to the table at the bottom of the right pane.

11. Click the Dashboard link at the top of Oracle Event Processing Visualizer.

    The Dashboard screen is displayed with the Management Events and Performance Monitoring panes as Figure 4-53 shows.

12. Click the name of the diagnostic profile in the table.

    The latency and throughput information is displayed in the graphs in the middle of the dashboard as Figure 4-53 shows.

    Figure 4-53 Oracle Event Processing Visualizer Dashboard With Diagnostic Profiles

    
    Description of "Figure 4-53 Oracle Event Processing Visualizer Dashboard With Diagnostic Profiles"
    
    

13. To expand the performance monitoring graphs to fill the screen, click Expand Chart.

14. To restore the performance monitoring graphs to their original size, click Restore Chart.

The Management Events section at the top of the Dashboard displays alerts about the incoming monitoring events. The Oracle Event Processing monitoring feature defines a set of default EPL rules that specify when these alerts show up in the Management Events table. You can change the EPL rules to customize this behavior, as described in Section 7.4, "Changing the dataservices Application Event Filter Rule Using EPL."