[ 
https://issues.apache.org/jira/browse/HBASE-14004?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15046422#comment-15046422
 ] 

Duo Zhang commented on HBASE-14004:
-----------------------------------

I do not think we can benefit a lot from storing acked length to zookeeper. If 
we do it periodically, then we could still meet the problem that we flush 
things out and then crashed so the new acked length is not stored on zk yet. If 
we do it at every hflush synchronously, then I think zookeeper will be fucked 
up in a large cluster...

> [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)

Reply via email to