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From Patrick Hunt <ph...@apache.org>
Subject Re: Read-your-writes consistency?
Date Tue, 14 Jul 2009 16:27:37 GMT
Yes, this is a strong guarantee:
http://hadoop.apache.org/zookeeper/docs/current/zookeeperProgrammers.html#ch_zkGuarantees

Sync is only necessary if client A makes a change, then client B wishes 
to read that change with guarantee that it will see the successfully 
applied change previously made by A (this is typically only an issue if 
A & B communicate through some non-zk channel, such as direct socket 
connection btw A & B).

Patrick

Marc Frei wrote:
> Dear ZooKeeper users,
> 
> a short question about ZooKeeper's consistency model:
> 
> Does ZooKeeper support "read-your-writes consistency"? E.g., after
> having created a node, will the same client always find the newly
> created node via getChildren? If yes, is this specified behavior the
> client can rely on? Or is it better to always call sync in order to
> enforce consistency?
> 
> Thanks in advance and kind regards,
> 
> Marc

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