Highly Available Client Event Mechanism
One of the key feature features of Geode is reliable asynchronous event notification. The publish/subscribe systems system offers a data distribution service where new events are published into the system and routed to all interested subscribers in a reliable manner.
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The product achieves reliability and HA (high availability) of the subscription event using HARegionQueue.
HARegionQueue
It’s HARegionQueue is an implementation of a queue using a Geode region as the underlying data structure.
When a client connects to the server with subscription enabled flag, a an HARegionQueue for that client-proxy is created on the server side.
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The client also acknowledges the server periodically with the received event Id ID (ThreadId, sequence IdID); for removal of events from HARegionQueue.
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