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Date: Mon, 08 Mar 2010 15:33:35 -0500
From: David Rosenstrauch <darose@darose.net>
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To: zookeeper-user@hadoop.apache.org
Subject: Re: Ok to share ZK nodes with Hadoop nodes?
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On 03/08/2010 02:21 PM, Patrick Hunt wrote:
> See the troubleshooting page, some apropos detail there (esp relative to
> virtual env).
>
> http://wiki.apache.org/hadoop/ZooKeeper/Troubleshooting
>
> ZK servers are sensitive to IO (disk/network) latency. As long as you
> aren't very sensitive latency requirements it should be fine. If the
> machine were to swap for example, or the JVM were to go into long term
> GC (visualization in particular kills jvm gc) that would be bad.
>
> Best practice for "on-line production serving" is 5 dedicated hosts with
> "shared nothing", physically distributed thoughout the data center (5
> hosts in a rack might not be the best idea for super reliability).
> There's alot of lee-way though, many ppl run with 3 and spof on switch
> for example.
>
> Patrick

Thanks much for the advice, Patrick.  (And Mahadev.)

DR