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


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Re: order of async requests to zookeeper
Ted,
 ZK does not re order async requests. They will be executed in the
same order as you call them from the same zk handle. Does that help?

thanks
mahadev

On Fri, Dec 23, 2011 at 10:43 AM, Ted Yu <[EMAIL PROTECTED]> wrote:
> The requests come from same zhandle.
>
> Cheers
>
> On Thu, Dec 22, 2011 at 6:09 PM, Ted Yu <[EMAIL PROTECTED]> wrote:
>
>> 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
>>