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https://issues.apache.org/jira/browse/HBASE-16417?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15615299#comment-15615299
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Edward Bortnikov commented on HBASE-16417:
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Just to give a sense of what we've been thinking as possible auto-tuning policy 
(smile). It's a "war driving" approach that is actually similar to 
opportunistic scans we had once but is a bit smarter.  Suppose we do full 
(data) compaction once in a while; a by-product is the compaction factor - how 
much space we saved. If the latter is small - schedule the next compaction 
further away, using some exponential backoff scheme. For workloads with very 
few duplicates - compactions will never happen, de-facto. For skewed workloads, 
compactions will consistently prove valuable, and will run at a constant pace. 

Note that the above is unrelated to whether we flush just one or all segments 
in the pipeline once the disk flush time comes. Personal opinion - no problem 
with flushing everything if this shows value. Let's wait for more benchmark 
results, they're just around the corner. One more personal opinion - we should 
strive to a generic policy, as much independent as possible on whether we use 
MSLAB's or not, run on-heap or off-heap, etc.; let's see if we can get there. 

Actually it's the most fun stage now - we have all the building blocks, the 
goal is connecting them right :) Stay tuned, we'll keep sharing the results and 
the ideas.  

> In-Memory MemStore Policy for Flattening and Compactions
> --------------------------------------------------------
>
>                 Key: HBASE-16417
>                 URL: https://issues.apache.org/jira/browse/HBASE-16417
>             Project: HBase
>          Issue Type: Sub-task
>            Reporter: Anastasia Braginsky
>            Assignee: Eshcar Hillel
>             Fix For: 2.0.0
>
>




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