Configuring the Decision Data Store service

View the current status of the Decision Data Store service and manage all Pega Platform nodes that are configured to store the data that is used in decision management, such as customer data. The Decision Data Store service stores data in JSON format for each customer from the sources configured to write to the Decision Data Store through data set instances. The data is distributed and replicated around the cluster of decision data nodes, and stored in the file system of each decision data node in a Cassandra database.
To optimize the performance of operations on customer data, the data for a specific customer is stored on the same node even if the data is on different nodes. You can add extra Decision Data Store nodes to increase the volume of data that is handled by your decision management processes or to reduce latency in making decisions.
  1. In the header of Dev Studio, click Configure > Decisioning > Infrastructure > Services > Decision Data Store.
  2. Add a node:
    1. Click Add node.
    2. In the window that is displayed, select the check box for the decision data node that you want to add. You can add multiple nodes at once.
    3. Click Submit.
    4. Refresh the landing page until the status of the node changes to NORMAL.
    Note: You need at least one decision data store node to run the Adaptive Decision Manager and Visual Business Director services. If you want to add a node for the ADM or VBD service and no nodes are on the Decision Data Store tab, a node is automatically added on that tab to support running the ADM or VBD service.
  3. Optional: To edit the Cassandra database credentials that were specified during the Pega Platform installation, click Edit settings .
    1. Select the Use external Cassandra cluster check box if you want to use a database that is external to Pega Platform for handling decision management data.
      • In the Cassandra host(s) field, enter a comma-separated list of Cassandra host names or IP addresses.
      • Edit the default Cassandra Query Language (CQL) port.

      To connect to the D-Node cluster by using third-party or custom tools to load or extract data through the Thrift protocol, specify port 9160 or to use the CQL3 Cassandra protocol, specify port 9042.

    2. Change the default Cassandra user ID and password. Use the credentials for the external Cassandra database.
      Note: When you decide to switch back to internal Cassandra, change the Cassandra user ID and password to dnode_ext .
    3. Select a logging level.
      • None
      • Error
      • Warn
      • Debug

      For more information about Cassandra driver loggers, see the DataStax documentation for Cassandra.

  4. Optional: Display the details for a node by clicking the row for that node. You can view information about the node ID, the total memory used, and the percent of the total amount of decision data that the node contains.
  5. Optional: Manage a node by selecting an action from the Execute menu.