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From Ravi Prakash <ravihad...@gmail.com>
Subject Re: datanode to blocks mapping
Date Wed, 15 Feb 2012 13:27:40 GMT
Selwa,

You are *creating* a new BlocksMap with the first line. It is NOT an API to
get the blockmap from the namenode. The Namenode stores its blocks in a
Blockmap in the BlockManager (for 0.23) or FSNameSystem (for 0.20)

Which version are you using?

Regards,
Ravi.

On Sat, Feb 11, 2012 at 7:41 PM, Selwa <elhamab99@gmail.com> wrote:

> Hello there,
> currently i am working on research about the block placement policy of
> HDFS.
> I want to find the blocks mapping of the pseudo cluster.
> then i request the name node for this data structure by the following code
>
>       BlocksMap blocksMap = new BlocksMap(16, 0.75f);
>      Collection<BlockInfo>blocks = blocksMap.getBlocks();
>              but the collection does not hold any thing - always it is
> empty
>             blocks.isempty() is becoming true even i saved some files on
> the pseudo -cluster.
> what is wrong with this code?
> is there any other way to find block mapping?
>
> thanks
>
> Selwa
>
> --
> View this message in context:
> http://lucene.472066.n3.nabble.com/datanode-to-blocks-mapping-tp3736421p3736421.html
> Sent from the Hadoop lucene-dev mailing list archive at Nabble.com.
>

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