Yes. That is why you should consider striping across raid 0 (JBOD)


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On Wed, Nov 12, 2014 at 9:09 AM, Brian C. Huffman <bhuffman@etinternational.com> wrote:
That will make the volume balancing easy, but couldn't it hurt performance?  My understanding is that there would be three write threads pointing to the 3TB disk and 2 threads pointing to the 2TB disk.

Would it be better from a performance perspective to include the 500GB drive in the configuration and just use the AvailableSpaceVolumeChoosingPolicy from the beginning?

Thanks,
Brian

On 11/12/2014 11:47 AM, Leonid Fedotov wrote:
Create 1 Tb partitions for 2 and 3 TB drives and you will have 5 mount points same size.


Thank you!


Sincerely,

Leonid Fedotov

Systems Architect - Professional Services

lfedotov@hortonworks.com

office: +1 855 846 7866 ext 292

mobile: +1 650 430 1673


On Wed, Nov 12, 2014 at 8:36 AM, Brian C. Huffman <bhuffman@etinternational.com> wrote:
All,

I'm setting up a 4-node Hadoop 2.5.1 cluster.  Each node has the following drives:
1 - 500GB drive (OS disk)
1 - 500GB drive
1 - 2 TB drive
1 - 3 TB drive.

In past experience I've had lots of issues with non-uniform drive sizes for HDFS, but unfortunately it wasn't an option to get all 3TB or 2TB drives for this cluster. 

My thought is to set up the 2TB and 3TB drives as HDFS and the 500GB drive as intermediate data.  Most our of jobs don't make large use of intermediate data, but at least this way, I get a good amount of space (2TB) per node before I run into issues.  Then I may end up using the AvailableSpaceVolumeChoosingPolicy to help with balancing the blocks.

If necessary I could put intermediate data on one of the OS partitions (/home).  But this doesn't seem ideal.

Anybody have any recommendations regarding the optimal use of storage in this scenario?

Thanks,
Brian


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