Aeron Messaging 6M mesgs/sec

Aeron: Do We Really Need Another Messaging System

At its core Aeron is a replicated persistent log of messages. And through a very conscious design process messages are wait-free and zero-copy along the entire path from publication to reception. This means latency is very good and very predictable.

It’s not a full featured messaging product in the way you may be used to, like Kafka. Aeron does not persist messages, it doesn’t support guaranteed delivery, nor clustering, nor does it support topics. Aeron won’t know if a client has crashed and be able to sync it back up from history or initialize a new client from history.

Aeron - Martin Thompson

Aeron - github

Design Principles



  • Garbage free in steady state running
  • Apply Smart Batching in the message path
  • Wait-free algorithms in the message path
  • Non-blocking IO in the message path
  • No exceptional cases in the message path
  • Apply the Single Writer Principle
  • Prefer unshared state
  • Avoid unnecessary data copies

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