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https://issues.apache.org/jira/browse/HBASE-14757?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14989838#comment-14989838
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Andrew Purtell commented on HBASE-14757:
----------------------------------------

Thanks Anoop. I'm expecting the changes we're making for off-heaping will make 
working in trunk both easier and more difficult. I believe targeted changes to 
prior versions should be more straightforward. I might actually prototype in 
branch-1. 

> Reduce allocation pressure imposed by HFile block processing
> ------------------------------------------------------------
>
>                 Key: HBASE-14757
>                 URL: https://issues.apache.org/jira/browse/HBASE-14757
>             Project: HBase
>          Issue Type: Improvement
>            Reporter: Andrew Purtell
>            Assignee: Andrew Purtell
>             Fix For: 2.0.0, 1.2.0, 1.3.0, 0.98.17
>
>
> Using Flight Recorder to look at the object allocation profiles of 
> regionservers processing the various YCSB workloads when block encoding is 
> enabled (specifically, FAST_DIFF, but this applies to any), we can see:
> - Allocations of byte[] for block encoding contribute 40-70% of all 
> allocation pressure in TLABs. 
> - Of that subset of allocation pressure, ~50-70% is byte[] for SeekerState
> - Greater than 99% of allocation of byte[] outside of TLABs are for read 
> buffers for HFileBlock#readBlockDataInternal.
> This issue is for investigation of strategy for and impact of reducing that 
> allocation pressure. Reducing allocation pressure reduces demand for GC, 
> which reduces GC activity overall, which reduces a source of system latency.



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