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Zookeeper >> mail # dev >> order of async requests to zookeeper


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order of async requests to zookeeper
Hi,
The following originated from discussion on a feature in HBase which relies
on zookeeper for coordination.

A task is removed from the tasks map. An async ZK request is pending to
remove the task's zk node.

 Another request arrives for this to-be-deleted task. A new in-memory task
structure is created. A ZK request is scheduled to create the same task
node.

 Problem will only occur if create-node executes before delete-node in ZK.
(If create-node returns NODEEXISTS then we treat that as success).

Does ZK re-order async requests?

Thanks