Page History

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• SEDA for in-JVM load balancing across a thread pool]
• ActiveMQ or JMS for distributed load balancing and parallel processing
• JPA for using the database as a poor mans message broker

When procssing processing messages concurrently, you should consider ordering and concurrency issues. These are described below

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Note that there is no concurrency or locking issue when using ActiveMQ, JMS or SEDA by design; they are designed for highly concurrent use. However there are possible concurrency issues in the Processor of the messages i.e. What what the processor does with the message?

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As soon as you send multiple messages to different threads or processes you will end up with an unknown ordering across the entire message stream as each thread is going
to process messages concurrently.

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