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Date: Mon, 15 Mar 2010 20:47:02 -0400
Message-ID: <9dba5ed31003151747p48c2892fv57bf94eb4075d1e7@mail.gmail.com>
Subject: persistent storage and node recovery
From: Maxime Caron <maxime.caron@gmail.com>
To: zookeeper-user@hadoop.apache.org
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Hi everybody,

>From what i understand Zookeeper consistency model work the same way as does
Scalaris.
Which is to keep the majority of the replica for an item UP.

In Scalaris i

f a single failed node does crash and recover, it simply start like a fresh
new node and all data is lost.

This is the case because it may otherwise get some inconsistencies as
another node already took over.

For a short timeframe there might be more replicas in the system than
allowed, which destroys the proper functioning of our majority based
algorithms.

So my question is how Zookeeper use the persistent storage during node
recovery, how does the

majority based algorithms is different so consistency is preserved.


Thanks a lots

Maxime Caron

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