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From: Michael Bieniosek <michael@powerset.com>
To: Cagdas Gerede <cagdas.gerede@gmail.com>, "core-user@hadoop.apache.org"
	<core-user@hadoop.apache.org>
Date: Mon, 14 Apr 2008 17:16:06 -0700
Subject: Re: How often Name node fails?
Thread-Topic: How often Name node fails?
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>From my experience, the namenode almost never crashes.  It does use a lot o=
f RAM, but not nearly as much as it used to.  You might have problems if yo=
u have many many small files (maybe 100,000s?).

I have had more problems with datanode failures, particularly when there is=
 mapreduce-generated load on the machines running the datanodes.

-Michael

On 4/14/08 3:14 PM, "Cagdas Gerede" <cagdas.gerede@gmail.com> wrote:

>From your experience with Hadoop Distributed File System,
how reliable is the namenode? How often does it fail? Are there mechanisms
developed outside of Hadoop to make namenode more fault tolerant?

Thanks for your feedback,


--
------------
Best Regards, Cagdas Evren Gerede
Home Page: http://cagdasgerede.info


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