About Capacity and Refill Level for the IBM webMethods Messaging Trigger Queue

On Integration Server, the IBM webMethods messaging trigger queue contains documents waiting for processing. Integration Server assigns each IBM webMethods messaging trigger a queue. A document remains in the IBM webMethods messaging trigger queue until it is processed by the IBM webMethods messaging trigger.

You can determine the capacity of each IBM webMethods messaging trigger queue. The capacity indicates the maximum number of documents that Integration Server can store for that IBM webMethods messaging trigger.

For IBM webMethods messaging trigger that receives documents from the IBM webMethods Broker, you can also specify a refill level to indicate when Integration Server should retrieve more documents for the IBM webMethods messaging trigger. The difference between the capacity and the refill level determines up to how many documents the Integration Server retrieves for the IBM webMethods messaging trigger from the IBM webMethods Broker. For example, if you assign the IBM webMethods messaging trigger queue a capacity of 10 and a refill level of 4, the Integration Server initially retrieves 10 documents for the IBM webMethods messaging trigger. When only 4 documents remain to be processed in the IBM webMethods messaging trigger queue, Integration Server retrieves up to 6 more documents. If 6 documents are not available, Integration Server retrieves as many as possible.

For IBM webMethods messaging trigger that receives documents from the IBM webMethods Broker, the capacity and refill level also determine how frequently Integration Server retrieves documents for the IBM webMethods messaging trigger and the combined size of the retrieved documents, specifically:

The greater the difference between capacity and refill level, the less frequently Integration Server retrieves documents from the IBM webMethods Broker. However, the combined size of the retrieved documents will be larger.

The smaller the difference between capacity and refill level, the more frequently Integration Server retrieves documents. However, the combined size of the retrieved documents will be smaller.

Note:
A refill level can be set for IBM webMethods messaging triggers that receive documents from the IBM webMethods Broker only. Refill level does not apply to IBM webMethods messaging triggers that receive documents from Universal Messaging.

For IBM webMethods messaging trigger that receives messages from Universal Messaging, Integration Server receives documents for the trigger one at a time until the trigger queue is at capacity. After the number of documents in the trigger queue equals the configured capacity, Integration Server stops receiving documents. When the number of documents awaiting processing in the trigger queue is less than the configured capacity, the trigger resumes receiving messages from Universal Messaging.