I'm having a bit of trouble with understanding JMS from a performance perspective. We have this very straightforward code in our application:
QueueConnection connection = null;
QueueSession session = null;
QueueSender sender = null;
TextMessage msg = null;
try {
// The JNDIHelper uses InitialContext to look up things
QueueConnectionFactory qcf = JNDIHelper.lookupFactory();
Queue destQueue = JNDIHelper.lookupQueue();
// These objects are created for every message, which is quite slow
connection = qcf.createQueueConnection();
session = connection.createQueueSession(false, Session.AUTO_ACKNOWLEDGE);
sender = session.createSender(destQueue);
// This is the actual message
msg = session.createTextMessage(xmlMsg);
sender.setTimeToLive(0);
sender.send(msg);
}
finally {
// Close all objects again
JMSUtilities.safeClose(sender);
JMSUtilities.safeClose(session);
JMSUtilities.safeClose(connection);
}
The code is correct, but probably some of the above artefacts could be reused for several messages. These are our configurations:
QueueConnection
, QueueSession
, QueueSender
) in memory as there is no concurrency involved.Here are some relevant parts of the jms spec:
section 2.8 Multithreading
JMS Object Supports Concurrent Use
Destination YES
ConnectionFactory YES
Connection YES
Session NO
MessageProducer NO
MessageConsumer NO
section 4.4.14 Serial Execution of Client Code
JMS does not cause concurrent execution of client code unless a client explicitly requests it. One way this is done is to define that a session serializes all asynchronous delivery of messages
So as already mentioned reuse as much as possible. Reuse the ConnectionFactory, Connection and Destinations for all Threads. For each Thread reuse consumers and producers.
If you are reusing a JMS connection beware, that the JMS Provider will multiplex different sessions on that connections. So even if it is safe to reuse connections it might be faster to create a connection for every session you need.