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From Mahadev Konar <maha...@yahoo-inc.com>
Subject Re: Watcher guarantees
Date Fri, 13 Feb 2009 18:21:39 GMT
> If client sets a watcher on a znode by doing a getData operation is it
> guaranteed to get the next change after the value it read, or can a
> change be missed?
The watch is just a notification that the node changed. If you do a getData
on the node, you their might have been more updates on the node.
So yes, you can miss changes.
> 
> In other words if the value it read had zxid z1 and the next update of
> the znode has zxid z2, will the watcher always get the event for the
> change z2?
>
The watcher will always get an event for zxid z2, but since the watch does
not have the data with it -- it will have to do getdata for the that node.
 
> Thanks,
> Tom
Mahadev


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