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From: Gustavo Niemeyer <gustavo@niemeyer.net>
Date: Wed, 1 Jul 2009 14:34:23 -0300
Message-ID: <643d90130907011034i3bb3f01arc6e1da770edebdab@mail.gmail.com>
Subject: Re: Dynamic servers addition and persistent storage.
To: zookeeper-user@hadoop.apache.org
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Hi again Henry,

> I hope to have a patch for both fairly soon. I should at least get ZK-368 to
> a workable position this week, and ZK-107 will hopefully not be an enormous
> amount of work on top of that. However, there doubtless be some slack time
> for picking up bugs etc. before it gets committed as it will be a reasonably
> sized patch.

That's great news.  I've added myself as a watcher on both tickets.

> Out of interest, what's your application for this?

I guess the same basic idea that everyone else has for it: bringing
additional systems up and down dynamically to control scalability and
reliability vs. cost of having many machines running at once.  I
understand it is possible to restart the servers one at a time to
change the server list without a full stop, but if we end up bundling
this in some open source framework for people to use in the wild, the
least manual interaction and procedural maintenance the best.  Having
ZooKeeper clients learning about the server list dynamically will help
a lot in this scenario too.

-- 
Gustavo Niemeyer
http://niemeyer.net