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Date: Fri, 2 Jul 2010 16:13:35 +1000
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Subject: Why single thread for HDFS?
From: elton sky <eltonsky9404@gmail.com>
To: general@hadoop.apache.org
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I guess this question was igored, so I just post it again.

>From my understanding, HDFS uses a single thread to do read and write.
Since a file is composed of many blocks and each block is stored as a file
in the underlying FS, we can do some parallelism on block base.
When read across multi-blocks, threads can be used to read all blocks. When
write, we can calculate the offset of each block and write to all of them
simultaneously.

Is this right?

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