This topic describes using more than one input node.
You can include more than one input node
in a single message flow. You might find this useful in the following situations:
- The message flow provides common processing for messages that are received
across multiple transports. For example, a single message flow might handle:
- Data in messages received across WebSphere MQ,
and therefore through a WebSphere MQ queue and
an MQInput node
- Messages that are received across native IP connections (a Real-timeInput node)
- You need to set standard properties on the MQInput node
if input messages:
- are predefined, and
- are all received across WebSphere MQ, and
- do not include an MQRFH2 header.
If the required standard properties are not always the same for every
message, you can include more than one input node and configure each to handle
a particular set of properties. This requirement is not necessary
for self-defining messages.
- Each input node in a message flow causes the broker to start a separate
thread of execution. Including more than one input node might improve the
message flow performance. However, if you include multiple input nodes that
access the same input source (for example, a WebSphere MQ queue),
the order in which the messages are processed cannot be guaranteed. If you
want the message flow to process messages in the order in which they are received,
this option is not appropriate.
If you are not concerned about message
order, consider using additional instances of the same message flow rather
than multiple input nodes. If you set the Additional
Instances property of the message flow when you deploy it to the
broker, multiple copies of the message flow are started in the execution group.
This is the most efficient way of handling multiple instances.
The Scribble sample uses two input
nodes: an MQInput node and a Real-timeInput node. Using these two
input nodes enables the sample's message flow to accept input across both
WebSphere® MQ
transport and native IP connections. You can view samples only when you use the information center
that is integrated with the Message Brokers Toolkit.