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https://issues.apache.org/jira/browse/HBASE-20708?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16507828#comment-16507828
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Duo Zhang commented on HBASE-20708:
-----------------------------------

After reading HBASE-19287, I tend to change my mind, that RMP is not a good 
idea for meta recovery at startup. There is no way to make sure that the meta 
region is online, as a server crash can happen at any time. So we should not 
make assumption that the meta region is online when designing or writing code.

Let me think more on how to fix it. I think this will not go into 2.0, as after 
HBASE-20700 the code is kinda 'stable', which means it is not easy to hit the 
corner cases which make you dead.

Thanks.

> Make sure there is no race between the RMP scheduled when start up and the SCP
> ------------------------------------------------------------------------------
>
>                 Key: HBASE-20708
>                 URL: https://issues.apache.org/jira/browse/HBASE-20708
>             Project: HBase
>          Issue Type: Sub-task
>          Components: proc-v2, Region Assignment
>            Reporter: Duo Zhang
>            Priority: Critical
>             Fix For: 3.0.0, 2.1.0, 2.0.1
>
>
> In HBASE-20700, we make RecoverMetaProcedure use a special lock which is only 
> used by RMP to avoid dead lock with MoveRegionProcedure. But we will always 
> schedule a RMP when master starting up, so we still need to make sure that 
> there is no race between this RMP and other RMPs and SCPs scheduled before 
> the master restarts.



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