The Limit Concurrency action and the Release Concurrency action are on the Flow tab in Rule Builder.

 
The Limit Concurrency action has two parameters:

1. Concurrent Limit—the maximum number of concurrent executions of rule sets using the specified limiter name.
2. Limiter Name—the name of the limiter. Usually there is one name for each rule set that should be limited. One suggestion would be to use the rule set full path name.

Notes:

• The limiter name should be tied to the rule set and always the same. Do not use the same rule set with a different limiter name each time it is invoked—for example by using the job name as the limiter name. This will work in the short term but over time will cause performance issues.
• Care should be taken when copying rule sets that use the Limit Concurrency action to ensure the limiter name is changed if necessary. Multiple rule sets can share a limiter name—their actions within the scope of the limiter will then be synchronized together—but this is a special use case that should be implemented with caution.

The Release Concurrency action has no parameters. It is automatically configured to release the limiter on the previous Limit Concurrency action.

There are two ways these actions can be used in a rule chain:

• Limit Concurrency action on its own which limits the execution of a rule chain from the action until the end of the chain
• Limit Concurrency and Release Concurrency actions together which limits the execution of a subset of the rule chain delimited by the two actions