zookeeper-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Chris Nauroth <cnaur...@hortonworks.com>
Subject Re: out of order callbacks of events in ZK
Date Fri, 06 Nov 2015 20:41:22 GMT
Hello Kamel,

The behavior you're seeing is not at odds with ZooKeeper's guarantees.
For more details, please refer to the ZooKeeper programmer's guide
statements on consistency guarantees.


In particularly, note the sidebar describing how ZooKeeper does not
guarantee simultaneously consistent cross-client views.

--Chris Nauroth

On 11/6/15, 12:32 PM, "kamel zaarouri" <kamel.zaarouri@gmail.com> wrote:

>Hi zk-users,
>Assume this tree:
>|         |____Child1
>         |_____<empty>
>I have 1 watchers on parent1 and another watcher on parent2. I have those
>watchers setup to receive updates of the child nodes of both parents.
>Child1 is a non-ephemeral node.
>If another client:
>- Creates an ephemeral node (let's call it ephem2) under parent2
>then and only then it
>- Updates Child1
>What I am seeing now is that 20% of the time, I receive the callbacks out
>of order, i.e. I see the Child1 being updated before ephem2 is seen
>Is this is a bug in the client I am using or does ZK not guarantee order
>this way?
>Thank you!,

View raw message