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https://issues.apache.org/jira/browse/HBASE-3588?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13002344#comment-13002344
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Ted Yu commented on HBASE-3588:
-------------------------------

The following change in MemStore would make TestHeapSize pass:
{code}
  public final static long FIXED_OVERHEAD = ClassSize.align(
      ClassSize.OBJECT + (12 * ClassSize.REFERENCE));
{code}


> Proposal to optimize ReadWriteConsistencyControl
> ------------------------------------------------
>
>                 Key: HBASE-3588
>                 URL: https://issues.apache.org/jira/browse/HBASE-3588
>             Project: HBase
>          Issue Type: Improvement
>          Components: regionserver
>            Reporter: dhruba borthakur
>            Assignee: dhruba borthakur
>         Attachments: rwcc.trunk.1, rwcc.trunk.1
>
>
> The ReadWriteConsistencyControl (RWCC) mechanism facilitates making a set of 
> memstore updates atomically visible to readers. Also, the 
> rwcc.completeMemstoreInsert() blocks till the memstore read point advances to 
> the current writeNumber. This is done to ensure that if an application that 
> does a put immediately issues a new get call for the same key, then the get 
> should see the values inserted by the previous call to put. The current 
> implementation assumes this worst-case and penalizes the put rpc to not 
> return to the client until the read point advances to this transaction's 
> write number.
> In many use-cases, the application never actually issues a get for the most 
> recent put that it inserted. In this case, it would be nice if we can 
> transfer the penalty (of blocking) to the get call that follows the initial 
> put.

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