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Date: Wed, 15 Aug 2012 18:11:04 -0400
From: David Rosenstrauch <darose@darose.net>
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To: user@hadoop.apache.org
Subject: OK to run data node on same machine as secondary name node?
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I have a Hadoop cluster that's a little tight on resources.  I was 
thinking one way I could solve this could be by running an additional 
data node on the same machine as the secondary name node.

I wouldn't dare do that on the primary name node, since that machine 
needs to be extremely performant.  But since all the secondary name node 
does is doing a merge of the name node's checkpoint and logs, which is 
not an activity that require top-notch real-time performance, I thought 
it might not be a problem if I were to set up a data node running there 
as well.

Any reasons why that might be a bad idea?

Thanks,

DR