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Subject: Re: blog post about zk and group membership
From: Adam Rosien <adam@rosien.net>
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Thanks Patrick.

Re "off the shelf", my title of "Actually Implementing" was a *bit*
snarky to try and gain some readers, but it wasn't intended to be
sharp criticism; more documented recipes is a good thing for everyone.
I'd be happy to submit a JIRA with a group membership recipe.

Re zkclient, I agree that documentation is a big thing, which I hope
to help out with as I use it more. I'm talking now with one of the
developers about zkclient's implementation of data serialization since
that is another big area; zk pushes all serialization semantics into
the clients, which is ok but requires its own practical strategies.

.. Adam

On Mon, Jan 11, 2010 at 9:49 AM, Patrick Hunt <phunt@apache.org> wrote:
> Adam, this is awesome! I've retweeted it on my twitter account:
> http://twitter.com/phunt/status/7637054275
>
> A few comments:
>
> 1) you are correct about the "off the shelf" part, but really alot of that
> is our marketing blurb, we paint with a broad stroke. I think it would make
> sense to include this sort of detail in the "recipes" page though, would you
> be interested to create a JIRA and submit some content? (you could re
> purpose alot of what you have in your post)
>
> 2) re zkclient - I have not been following that project closely of late,
> however Mahadev and I did review their code a few months ago. At that time
> we had some concerns about the semantic impact of some of the design choices
> they made (which were fine, just not well documented and therefor easy for
> users to miss). In particular (again, at the time, may be addressed by now)
> watch notifications could be lost during disconnected/expired sessions, and
> the user would not be made aware of this.
>
> 3) excellent point/suggestion on the "rogue" service
>
> Patrick
>
> Adam Rosien wrote:
>>
>> I've written a blog post about using ZooKeeper for group membership at
>> KaChing:
>>
>> http://bit.ly/6yraP6
>> http://eng.kaching.com/2010/01/actually-implementing-group-management.html
>>
>> Any comments or feedback is welcome.
>>
>> .. Adam
>