[jira] [Created] (HBASE-11314) Remove MultiVersionConsistencyControl#writeQueue

["Jeffrey Zhong (JIRA)" <ji...@apache.org>]

Jeffrey Zhong created HBASE-11314:
-------------------------------------

             Summary: Remove MultiVersionConsistencyControl#writeQueue
                 Key: HBASE-11314
                 URL: https://issues.apache.org/jira/browse/HBASE-11314
             Project: HBase
          Issue Type: Improvement
            Reporter: Jeffrey Zhong
             Fix For: 0.99.0


This is a follow up improvement of HBase-8763. After we combined MVCC & LogSeqId, the memstore read point advances in the logSeqId increasing order. The MultiVersionConsistencyControl#writeQueue can be possibly removed.

In order to remove writeQueue, we need to return the disruptor sequence of the last WALEdit with durability >= SYNC_WAL inside disruptor consumer code before assigning log sequence Id. If current WALEdit has durability >= SYNC_WAL, we return the disruptor sequence of current WALEdit.

During syncOrDefer, we always waits for the sequence of the last WALEdit has durability >= SYNC_WAL.

The tricky part is how to return the disruptor sequence of the last WALEdit with durability >= SYNC_WAL cleanly from disruptor consumer. 

We could put those info in HLogKey because we always create a new HLogKey object for each change otherwise we have to create a new object for this purpose.




--
This message was sent by Atlassian JIRA
(v6.2#6252)