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Re: Understanding event interleaving
If I understand well your scenario, R will receive Version 2 and and event
is delivered to caller (R). In this scenario, the thread that has
registered the watch on node Z has to still be alive to receive the event.

On Thu, May 23, 2013 at 8:47 AM, Scott Fines <[EMAIL PROTECTED]> wrote:

> Hello all,
> This is perhaps a silly question, but one I'm not clear on.
> Suppose you have two clients (R and W), and they are interacting through
> znode Z. Now consider the following situation:
> 0. Z at version 1
> 1. R begins getData(Z) (attach Watcher)
> 2. W begins setData(Z)
> 3. W completed setData(Z) successfully --e.g. the client call returns with
> no errors
> 4. R completes getData(Z) successfully -- e.g. the client call returns
> with no errors
> My questions are then:
> 1. What version of data will R receive? Version 1, or Version 2? My
> assumption here is that R would receive version 1 of the data--is that
> correct?
> 2. Does R's watch fire with the changes made by W? If so, is a WatchEvent
> delivered all the way to the caller? A comment made on ZOOKEEPER-1505 (
> https://issues.apache.org/jira/browse/ZOOKEEPER-1505) implies that it
> would not, but I'm unclear if that is in reference to the proposed changes
> or not.
> Thanks for your help!
> Scott Fines