Aggregation (4.2)

Take into account the following behaviors when using the Aggregation profile:

You can apply an Aggregation profile to any number of workflow configurations.
Aggregation sessions created in the storage that is specified by the profile can be accessed by multiple active workflows simultaneously.
When you have selected file storage and are using an Aggregation profile across several workflow configurations, you must consider the read-and-write lock mechanisms that are applied to the stored sessions. For further information about read-and-write locks, see Aggregation Agent - Batch(4.2) and Aggregation Agent - Real-Time(4.2).
The Aggregation profile is loaded when you start a workflow that depends on it. Changes to the profile become effective when you restart the workflow.

Session UDR

Each Aggregation profile stores sessions of a specific Session UDR type that you define in ultra. This means that your Aggregation profile configuration must include a session UDR type. See the example below:

Example - Defining a Session UDR type in an Ultra Configuration

session SessionUDRType {
   int intField;
   string strField;
   list<drudr> udrList;
};

It is recommended that you keep the session UDR as small as possible. A larger UDR decreases performance compared to a small one.

Note!

Take particular care when updating the Ultra formats. It is not possible to collect data from the Aggregation session storage if the corresponding UDR has been renamed. However, if you change the format definition, you can still collect the data.

Changes to the formats are handled as follows:

Default values are assigned to fields that are added or renamed.
Fields that have been removed are ignored.
Default values are assigned to fields with data types that have been changed.

For further information on Ultra formats, see Ultra Format(4.2).

Profile Configuration

The contents of the buttons in the menu bar may change depending on which configuration type has been opened in the currently active tab. The Aggregation profile uses the standard buttons that are visible for all configurations, and these are described in Build View (4.2).

The profile consists of four tabs:

Session Tab
Association Tab
Storage Tab
Advanced Tab

Session Tab

In the Session tab you can browse to and select a Session UDR Type and configure the Storage selection settings.

The Aggregation profile configuration dialog - Session tab

Setting

Description

Session UDR Type

Click Browse… to search for the Session UDR type that you want to use. See Aggregation (4.2) | Session UDR above for information on creating a Session UDR type.

Storage

Select the type of storage for aggregation sessions. The available settings are:

Couchbase Storage
Elasticsearch Storage
File Storage
Memory Only
Redis Storage
SQL Storage

File Storage and Memory Only can be used in batch and real-time workflows.

Elasticsearch Storage and SQL Storage can only be used in batch workflows.

Couchbase Storage and Redis Storage can only be used in real-time workflows. These storage types allow highly available systems with geographic redundancy. The session data that is replicated within the storage is available across workflows, EC Groups, and systems. This serves to minimize data loss in failover scenarios.

Note!

Data stored in Couchbase or Redis is not available in the Aggregation Session Inspector(4.2).

Association Tab

You use the Association tab to configure rules to match an incoming UDR with a session. Every UDR type requires a set of rules that are processed in a certain order. In most cases, only one rule per incoming UDR type is defined.

You can use a primary expression to filter out UDRs that are candidates for a specific rule. If the UDR is filtered out by the primary expression, it is matched with the existing sessions by using one or several ID fields as a key.

For UDRs with ID Fields matching an existing session, an additional expression may be used to specify additional matching criteria. For example, if dynamic IP addresses are provided to customers based on time intervals, the field that contains the IP address could be used in ID Fields while the actual time could be compared in Additional Expression.

Setting	Description
UDR Types	Click the Add button to select a UDR type in the UDR Internal Format dialog. The UDR type that you select then appears in this field. A UDR type may have a list of rules attached to it. When you select the UDR type, its rules appear as separate tabs to the right in the Aggregation profile configuration.
Primary Expression	The Primary Expression is optional. You can enter an APL code expression to be evaluated before the ID Fields are evaluated. If the evaluation result is `false` the rule is ignored and the evaluation continues with the next rule. Use the `input` variable to write this filtering expression.
ID Fields	Click the Add button to select additional ID Fields in the ID Fields dialog. These fields, along with the Additional Expression settings, enable Usage Engine to determine whether a UDR belongs to an existing session or not. If the contents of the selected fields match the contents of a session and an Additional Expression evaluation results in `true`, the UDR belongs to the session.
Additional Expression	The Additional Expression is optional. Enter an APL code expression to be evaluated with the ID Fields. Use the `input` variable to write this filtering expression. This setting is useful when you have several UDR types with a varying number of ID Fields to be consolidated. Having several UDR types requires the ID fields to be equal in number and type. If one of the types requires additional fields that do not have any counterpart in the other type or types, these must be evaluated in the Additional Expression field. Save the field contents as a session variable, and compare the new UDRs with it.
Create Session on Failure	Select this check box to create a new session if no matching session is found. If the check box is not selected, a new session is not created when no matching session is found. If the order of the input UDRs is unimportant, select this check box for all the rules. This means that the session object is created regardless of the order in which the UDRs arrive. However, if the UDRs are expected to arrive in a particular sequence, only select Create Session on Failure for the UDR type/field that is considered to be the master UDR, i.e. the UDR that marks the beginning of the sequence. In this case, all the slave UDR types/fields are targeted for error handling if they arrive before their master UDR. For further information about all available system properties, see System Properties (4.2).
Add Rule	Click this button to add a new rule for the selected UDR type. The rule appears as a new folder to the right of the UDR types in the Aggregation profile configuration. Usually, only one rule is required. However, in a situation where a session is based on an IP number, stored in either a target or source IP field, two rules are required. The source IP field can be listed in the ID Fields of the first rule and the target IP field listed in the ID Fields of the second rule.
Remove Rule	Click this button to remove the selected rule.

Storage Tab

The Storage tab contains settings that are specific for File Storage, Couchbase Storage, Redis Storage, Elasticsearch Storage, and SQL Storage.

Couchbase Storage

Setting

Description

Profile

Select a Couchbase (4.2) profile. This profile is used to access the primary storage for aggregation sessions.

Mirror Profile

Selecting this Couchbase profile is optional. It is used to access a secondary storage, providing read-only access for aggregation sessions. Typically, the Mirror Profile is identically configured to a (primary) Profile, that is used by workflows on a different EC or other Usage Engine system. This is useful to minimize data loss in various failover scenarios. The read-only sessions can be retrieved with APL commands. For more information and examples, see Aggregation Functions(4.2).

Elasticsearch Storage

Setting	Description
Profile	Select an Elasticsearch (4.2) profile. This profile is used to access the storage for aggregation sessions.

File Storage

Setting	Description
Storage Host	You can only select Automatic. When you select Automatic, the EC used by the running workflow is automatically applied. Alternatively, if the Aggregation Session Inspector is used, a storage host is selected automatically. For further information, see Aggregation Session Inspector(4.2).
Directory	Enter the directory on the Storage Host where you want the aggregation data to be stored.
Partial File Count	In this field, you can enter the maximum number of partial files that you want to store. Consider the following: Startup: All the files are read at startup. It takes longer if there are many partial files. Transaction commitment: Many small files (large Partial File Count) increase performance when the transactions are committed. In a batch workflow, use this variable to tune performance.
Max Cached Sessions	Enter the maximum number of sessions to keep in the memory cache. This is a performance-tuning parameter that determines the memory usage of the Aggregation agent. Set this value to be low enough so that there is still enough space for the cache in memory, but not too low, as this will cause performance to deteriorate, see Performance Tuning with File Storage(4.2) for more information.
Enable Separate Storage Per Workflow	This option enables each workflow to have a separate session storage. Multiple workflows are allowed to run simultaneously using the same Aggregation profile. If this checkbox is selected, a workflow will never see a session from another workflow.

Memory Only

When you have selected Memory Only as storage, there are no additional settings in the Storage tab.

Redis Storage

Setting	Description
Profile	Select a Redis (4.2) profile. This profile is used to access the storage for aggregation sessions.

SQL Storage

Setting	Description
Profile	Select a Database Profile(4.2) configured with the SQL database type. This profile is used to access the storage for aggregation sessions.
Index Fields	Click the Add button to select the UDR type.
Table SQL Script	This text box will generate the SQL statements for the selected UDRs' table schema and indexes for Id, TxId. The schema will be generated based on the number of UDRs in the UDR Type Mapping table.

Advanced Tab

The Advanced tab is available when you have selected Couchbase Storage, Elasticsearch Storage, Redis Storage or SQL Storage in the Session tab. It contains properties that can be used for performance tuning. For information about performance tuning, see Aggregation Performance Tuning(4.2).

These fields supports parameterization using ${} syntax, see Profiles(4.2) for more information on how parameterization works.

Couchbase Storage

You can also set the properties listed in the Advanced tab as system properties in the ECD, see Creating an EC Deployment (4.2) , which will override the values that are set in the profile, including default values.

Elasticsearch Storage

For Elasticsearch storage, you can modify the properties listed as shown above in the Advanced tab.

Redis Storage

For Redis Storage, you can only modify the properties in the Advanced tab.

SQL Storage

For SQL Storage, you can modify the properties listed as shown above in the Advanced tab.