Using Statistics

If you want TIBCO BusinessEvents components to scale automatically (adding or removing engines), you can define rules that add or remove TIBCO Silver® Fabric engines based on engine statistics or BusinessEvents component statistics.

Data collected are aggregated. The aggregate is used to average raw statistic values by using a source ID. The average is calculated by individually averaging the statistic values for each source ID (for each engine), and then averaging the results across all engines.

For example, if a specific aggregated value triggers the rule, but the normalized geometric variance across the engines is less than 0.85, it does not add an engine. Removing engines is not affected by variance.

When an engine is added, it automatically publishes the BusinessEvents archive that was configured with the enabler component on a new engine. For HTTP activities, for example, for web services using SOAP over HTTP transport and HTTP receiver activities, the engine adds the URL to the load balancer automatically.

You can set up rules on enablement condition. The engine starts upon statistics rules on other engines. You also can set up rules on threshold activation, which is the statistic on the engine itself or other engines.