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Zookeeper, mail # user - Watching children updates


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Benjamin Jaton 2013-07-17, 23:25
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Flavio Junqueira 2013-07-18, 00:30
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Re: Watching children updates
Benjamin Jaton 2013-07-18, 01:23
Thanks, the JIRA is very interesting.

I am contemplating the possibility to make a parent.setData(..) call to
notify of a change in one of the children and put a watcher on
parent.getData().
I would then iterate through the children and compare the stat.getVersion()
to figure out which have changed.
On Wed, Jul 17, 2013 at 5:30 PM, Flavio Junqueira <[EMAIL PROTECTED]>wrote:

> Hi Ben,
>
> Your description seems right to me, assuming that when you refer to
> changes to the children, you mean setting the data of the children.
>
> You may also want to have a look here if you haven't done it yet:
>
>
> http://zookeeper.apache.org/doc/r3.4.5/zookeeperProgrammers.html#ch_zkWatches
>
> About performance impact, you may want to have a look at the discussion
> here:
>
>         https://issues.apache.org/jira/browse/ZOOKEEPER-1177
>
> -Flavio
>
> On Jul 18, 2013, at 12:25 AM, Benjamin Jaton <[EMAIL PROTECTED]>
> wrote:
>
> > Hello,
> >
> > I would like to be notified of a change on any of the children of a znode
> > (could be a lot of them).
> >
> > AFAIK to achieve this we need to set a watcher on each child and then
> also
> > watch the parent to be aware of children addition/deletion and add/remove
> > watchers accordingly. Is that correct?
> >
> > What is the performance impact of having for example thousands of
> watchers?
> >
> > Thanks,
> > Ben
>
>
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kishore g 2013-07-18, 05:50
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Thawan Kooburat 2013-07-18, 07:08