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https://issues.apache.org/jira/browse/HBASE-20706?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16506280#comment-16506280
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Josh Elser commented on HBASE-20706:
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{quote}Is it a hack?
{quote}
Well, it's a hack in a sense that we're using MoveRegionProcedure in a manner
which it was unintended to be used for (reopening). That's all.
{quote}If MTP runs and there are regions offline, when they are onlined,
they'll pick up the table edit?
{quote}
The problem is that I don't see the MTP giving up the table lock. The fast-spin
we have is wrapped inside of
\{{org.apache.hadoop.hbase.procedure2.ProcedureExecutor.executeProcedure(ProcedureExecutor.java:1240)}}.
The sub-procedures fail in MTP, that exception is caught+eaten, we bubble up
and (best as I can tell from logging), MTP resubmits itself, triggers the
{{reExecute}} flag in ProcedureExecutor and re-runs right away. So, my attempt
to do an {{assign}} in the hbase shell just hangs because we can never get in.
Maybe that is an issue just with how MTP is written – not sure.
> [hack] Don't add known not-OPEN regions in reopen phase of MTP
> --------------------------------------------------------------
>
> Key: HBASE-20706
> URL: https://issues.apache.org/jira/browse/HBASE-20706
> Project: HBase
> Issue Type: Sub-task
> Components: amv2
> Reporter: Josh Elser
> Assignee: Josh Elser
> Priority: Critical
> Fix For: 3.0.0, 2.1.0, 2.0.1
>
> Attachments: HBASE-20706.001.branch-2.0.patch
>
>
> Shake-down of ModifyTableProcedure, talked this one out with Stack – "proper"
> fix is likely pending in HBASE-20682. Using MoveRegionProcedure is likely the
> wrong construct, we would want something specific to reopen (e.g. a
> ReopenProcedure).
> However, we're in a really bad state right now. If there are non-open regions
> for a table which has a modify submitted against it, the entire system locks
> up in a fast-spin while holding the table's lock. This fills up HDFS with PV2
> wals, and prevents you from doing anything in the hbase shell to try to fix
> those unassigned regions. You'll see spam in the master log like:
> {noformat}
> 2018-06-07 03:21:29,448 WARN [PEWorker-1] procedure.ModifyTableProcedure:
> Retriable error trying to modify table=METRIC_RECORD_HOURLY_UUID (in
> state=MODIFY_TABLE_REOPEN_ALL_REGIONS)
> org.apache.hadoop.hbase.client.DoNotRetryRegionException:
> a3dc333606d38aeb6e2ab4b94233cfbc is not OPEN
> at
> org.apache.hadoop.hbase.master.procedure.AbstractStateMachineTableProcedure.checkOnline(AbstractStateMachineTableProcedure.java:193)
> at
> org.apache.hadoop.hbase.master.assignment.MoveRegionProcedure.<init>(MoveRegionProcedure.java:67)
> at
> org.apache.hadoop.hbase.master.assignment.AssignmentManager.createMoveRegionProcedure(AssignmentManager.java:767)
> at
> org.apache.hadoop.hbase.master.assignment.AssignmentManager.createReopenProcedures(AssignmentManager.java:705)
> at
> org.apache.hadoop.hbase.master.procedure.ModifyTableProcedure.executeFromState(ModifyTableProcedure.java:128)
> at
> org.apache.hadoop.hbase.master.procedure.ModifyTableProcedure.executeFromState(ModifyTableProcedure.java:50)
> at
> org.apache.hadoop.hbase.procedure2.StateMachineProcedure.execute(StateMachineProcedure.java:184)
> at
> org.apache.hadoop.hbase.procedure2.Procedure.doExecute(Procedure.java:850)
> at
> org.apache.hadoop.hbase.procedure2.ProcedureExecutor.execProcedure(ProcedureExecutor.java:1472)
> at
> org.apache.hadoop.hbase.procedure2.ProcedureExecutor.executeProcedure(ProcedureExecutor.java:1240)
> at
> org.apache.hadoop.hbase.procedure2.ProcedureExecutor.access$800(ProcedureExecutor.java:75)
> at
> org.apache.hadoop.hbase.procedure2.ProcedureExecutor$WorkerThread.run(ProcedureExecutor.java:1760)
> {noformat}
> We unstuck out internal test cluster giving the following change on top of
> Sergey's HBASE-20657. When choosing the regions to reopen, if we filter out a
> table's regions to only be those which are currently OPEN. There may be some
> transient failures here as well, but a subsequent retry of the reopen step
> should filter out that change.
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