Executing rulesets in the decision engine

In Rule Designer, you can extract and package your rules for execution on different platforms.

The decision engine optimizes the execution performance of your ruleset. Before deployment, Decision Center compiles the rules into executable code (Java™ bytecode) by default.

Rule Designer compiles the rules into executable code by default. Clear the Optimize ruleset loading (Java bytecode generation) option on the Export a Ruleset Archive page to compile the rules to intermediate code.

You can choose the Fastpath, sequential, or RetePlus execution mode. With the working memory and agenda features, you can store and manipulate application objects. The working memory contains references to the application objects. The agenda lists and orders the rule instances that are eligible for execution.

Workflow for running rules on the decision engine

To run rules with the decision engine, do the following steps:

  1. Create a rule project to encapsulate the business logic of your legacy applications.
  2. Test the execution of the rules in Rule Designer.
  3. After you create decision operations and deployment configurations, you can publish the decision service to Decision Center on the cloud.
  4. After you update the decision service in Decision Center on the cloud, you can deploy the modified decision service to the Rule Execution Server in the development environment.
  5. After you test and validating the decision service, you can deploy it to the production environment.

Compilation and execution

The decision engine compiles rule artifacts into an archive that contains compiled and optimized code that becomes executable when converted to Java bytecode. The ruleset archive .dsar file consists of binary files that contain execution code for the rules and ruleflows. You either deploy intermediate code or Java bytecode.

The following figure shows the process of compilation and execution for the decision engine, with or without Java bytecode generation. This process goes through different stages from the initial compilation of rules until the execution of rules.

Image shows a comparison between deploying intermediate code and Java bytecode.
Important: Bytecode generation improves the loading time of rulesets that are built with the decision engine. In Rule Designer and Decision Center, the bytecode generation option is selected by default.