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https://issues.apache.org/jira/browse/HBASE-5313?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13207057#comment-13207057
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He Yongqiang commented on HBASE-5313:
-------------------------------------

>>Can you also list the time it took writing the HFile for each of the three 
>>schemes ?
@Zhihong, we are still trying to explore more ideas here. Once we got a 
finalized plan, i will get the cpu/latency numbers. 


>>Yongqiang, what is the delta encoding algorithm did you use? The default 
>>algorithm only do a simple encoding. Do we have results using prefix with 
>>fast diff algorithm for the current hfile v2?

@jerry, i tried all three delta. And Diff with HFileWriterV2 is producing 
smallest file in my test. 





                
> Restructure hfiles layout for better compression
> ------------------------------------------------
>
>                 Key: HBASE-5313
>                 URL: https://issues.apache.org/jira/browse/HBASE-5313
>             Project: HBase
>          Issue Type: Improvement
>          Components: io
>            Reporter: dhruba borthakur
>            Assignee: dhruba borthakur
>
> A HFile block contain a stream of key-values. Can we can organize these kvs 
> on the disk in a better way so that we get much greater compression ratios?
> One option (thanks Prakash) is to store all the keys in the beginning of the 
> block (let's call this the key-section) and then store all their 
> corresponding values towards the end of the block. This will allow us to 
> not-even decompress the values when we are scanning and skipping over rows in 
> the block.
> Any other ideas? 

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