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Duo Zhang commented on HBASE-21375: ----------------------------------- Any other concerns? [~stack] [~allan163] Thanks. > Revisit the lock and queue implementation in MasterProcedureScheduler > --------------------------------------------------------------------- > > Key: HBASE-21375 > URL: https://issues.apache.org/jira/browse/HBASE-21375 > Project: HBase > Issue Type: Sub-task > Components: proc-v2 > Reporter: Duo Zhang > Assignee: Duo Zhang > Priority: Major > Fix For: 3.0.0, 2.2.0 > > Attachments: HBASE-21375-UT.patch, HBASE-21375-UT2.patch, > HBASE-21375-v1.patch, HBASE-21375-v2.patch, HBASE-21375.patch > > > The problem for the old implementation is that we will only check the first > procedure in a queue to see if it could run, if it can not, we will remove > the queue from run queue. So when adding procedure to the scheduler, we have > to try hard to put the procedure which can be executed in front of the queue, > if there are corner cases where we fail to do so, it will likely lead to a > dead lock, that's why we have the tricky code when loading procedures and try > to add them into the scheduler, and also lots of 'if' in the doAdd method of > MasterProcedureScheduler. But this is still not enough to make things right, > so finally [~allan163] and I decided to change the logic in doPoll method, > where we use a loop to find whether there is a procedure can be executed, not > only the first one. -- This message was sent by Atlassian JIRA (v7.6.3#76005)