hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Yu Li (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HBASE-14004) [Replication] Inconsistency between Memstore and WAL may result in data in remote cluster that is not in the origin
Date Tue, 08 Dec 2015 05:27:10 GMT

    [ https://issues.apache.org/jira/browse/HBASE-14004?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15046385#comment-15046385
] 

Yu Li commented on HBASE-14004:
-------------------------------

Assume this situation:
1. RS received an ack from DFSClient, and record it in memory, not on zk
2. ReplicationSource read from the last synced length, but RS crashed before it reach the
new ack length
3. Replication queue recovery starts on another RS, where no place to get the acked length
for the old-crashed RS
In this case, where will step 3 ends? If read until it reaches EOF, then the inconsistency
issue we try to resolve here happen again, right?

> [Replication] Inconsistency between Memstore and WAL may result in data in remote cluster
that is not in the origin
> -------------------------------------------------------------------------------------------------------------------
>
>                 Key: HBASE-14004
>                 URL: https://issues.apache.org/jira/browse/HBASE-14004
>             Project: HBase
>          Issue Type: Bug
>          Components: regionserver
>            Reporter: He Liangliang
>            Priority: Critical
>              Labels: replication, wal
>
> Looks like the current write path can cause inconsistency between memstore/hfile and
WAL which cause the slave cluster has more data than the master cluster.
> The simplified write path looks like:
> 1. insert record into Memstore
> 2. write record to WAL
> 3. sync WAL
> 4. rollback Memstore if 3 fails
> It's possible that the HDFS sync RPC call fails, but the data is already  (may partially)
transported to the DNs which finally get persisted. As a result, the handler will rollback
the Memstore and the later flushed HFile will also skip this record.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message