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From: Anoop Sam John <anoopsj@huawei.com>
To: "user@hbase.apache.org" <user@hbase.apache.org>
Subject: RE: HBase Checksum
Thread-Topic: HBase Checksum
Thread-Index: AQHOAAT2T+53rbgT9UiSvIgUjzM+P5hkXyc+
Date: Fri, 1 Feb 2013 03:55:00 +0000
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You can check with HDFS level logs whether the checksum meta file is gettin=
g read to the DFS client? In the HBase handled checksum, this should not ha=
ppen.
Have you noticed any perf gain when you configure the HBase handled checksu=
m option?

-Anoop-
________________________________________
From: Jean-Marc Spaggiari [jean-marc@spaggiari.org]
Sent: Friday, February 01, 2013 4:16 AM
To: user
Subject: HBase Checksum

Hi,

I have activated shortcircuit and checksum and I would like to get a
confirmation that it's working fine.

So I have activated short circuit first and saw a 40% improvement of
the MR rowcount job. So I guess it's working fine.

Now, I'm configuring the checksum option, and I'm wondering how I can
do to validate that it's taken into consideration and used, or not. Is
there a way to see that?

Thanks,

JM=