[ 
https://issues.apache.org/jira/browse/HDFS-503?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12749081#action_12749081
 ] 

dhruba borthakur commented on HDFS-503:
---------------------------------------

Hi Nicholas, I agree with you completely. The current patch implements basic 
xor. Once this patch is accepted by the community, I plan to make the algorithm 
pluggable, so that people can plug in more advanced erasure codes into the  
framework laid out by this patch.

If you have the time and energy, please review the patch and provide any 
feedback you may have. Thanks.

> Implement erasure coding as a layer on HDFS
> -------------------------------------------
>
>                 Key: HDFS-503
>                 URL: https://issues.apache.org/jira/browse/HDFS-503
>             Project: Hadoop HDFS
>          Issue Type: New Feature
>            Reporter: dhruba borthakur
>            Assignee: dhruba borthakur
>         Attachments: raid1.txt
>
>
> The goal of this JIRA is to discuss how the cost of raw storage for a HDFS 
> file system can be reduced. Keeping three copies of the same data is very 
> costly, especially when the size of storage is huge. One idea is to reduce 
> the replication factor and do erasure coding of a set of blocks so that the 
> over probability of failure of a block remains the same as before.
> Many forms of error-correcting codes are available, see 
> http://en.wikipedia.org/wiki/Erasure_code. Also, recent research from CMU has 
> described DiskReduce 
> https://opencirrus.org/system/files/Gibson-OpenCirrus-June9-09.ppt.
> My opinion is to discuss implementation strategies that are not part of base 
> HDFS, but is a layer on top of HDFS.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.

Reply via email to