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From Patrick Hunt <ph...@apache.org>
Subject Re: Simpler ZooKeeper event interface....
Date Wed, 07 Jan 2009 18:33:11 GMT
Kevin Burton wrote:
>> 3) it's possible for your code to get notified of a change, but never
>> process the change. This might happen if:
>>  a) a node changed watch fires
>>  b) your client code runs an async getData
>>  c) you are disconnected from the server
> Also, this seems very confusing...
> If I run an async request, the client should replay these if I'm reconnected
> to another host.

(Ben/Flavio/Mahadev can correct me if I'm wrong here or missed some detail)

Async operations are tricky as the server makes the change when it gets 
the request, not when the client processes the response. So you could 
request an async operation, which the server could process and respond 
to the client, immed. after which the client is disconnected from the 
server (before it can process the response). Client replay would not 
work in this case, and given that async is typically used for high 
throughput situations there could be a number of operations effected.


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