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https://issues.apache.org/jira/browse/HBASE-18005?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16006833#comment-16006833
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huaxiang sun commented on HBASE-18005:
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Yes, you are right about the worst case. There is no solution with this case as
it is same as the client comes up fresh and meta table is not available.
One minor correction is that besides the meta replicas waits for
hbase.regionserver.meta.storefile.refresh.period or
hbase.regionserver.meta.storefile.refresh.period(if
hbase.regionserver.meta.storefile.refresh.period is configured, it will take
hbase.regionserver.meta.storefile.refresh.period), it still needs to wait for a
flush of meta table's memstore.
> read replica: handle the case that region server hosting both primary replica
> and meta region is down
> -----------------------------------------------------------------------------------------------------
>
> Key: HBASE-18005
> URL: https://issues.apache.org/jira/browse/HBASE-18005
> Project: HBase
> Issue Type: Bug
> Reporter: huaxiang sun
> Assignee: huaxiang sun
> Attachments: HBASE-18005-master-001.patch
>
>
> Identified one corner case in testing that when the region server hosting
> both primary replica and the meta region is down, the client tries to reload
> the primary replica location from meta table, it is supposed to clean up only
> the cached location for specific replicaId, but it clears caches for all
> replicas. Please see
> https://github.com/apache/hbase/blob/master/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ConnectionImplementation.java#L813
> Since it takes some time for regions to be reassigned (including meta
> region), the following may throw exception
> https://github.com/apache/hbase/blob/master/hbase-client/src/main/java/org/apache/hadoop/hbase/client/RpcRetryingCallerWithReadReplicas.java#L173
> This exception needs to be caught and it needs to get cached location (in
> this case, the primary replica's location is not available). If there are
> cached locations for other replicas, it can still go ahead to get stale
> values from secondary replicas.
> With meta replica, it still helps to not clean up the caches for all replicas
> as the info from primary meta replica is up-to-date.
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