[ 
https://issues.apache.org/jira/browse/HBASE-21487?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16698982#comment-16698982
 ] 

Syeda Arshiya Tabreen commented on HBASE-21487:
-----------------------------------------------

No, I'm not preparing any patch as of now,I was just thinking about the 
solutions and did not get any clear approach.
when do we release the table lock if we grab the lock before constructing the 
new table descriptor? As per my understanding, when we release the lock before 
submitting the procedure, the issue wont be solved as the descriptor will 
override and it will lead to same unexpected results.If we release after 
submitting the procedure,the ModifyTableProcedure won't start until the table 
lock is released.Is this right?

> Concurrent modify table ops can lead to unexpected results
> ----------------------------------------------------------
>
>                 Key: HBASE-21487
>                 URL: https://issues.apache.org/jira/browse/HBASE-21487
>             Project: HBase
>          Issue Type: Bug
>    Affects Versions: 3.0.0, 2.0.0
>            Reporter: Syeda Arshiya Tabreen
>            Priority: Major
>
> Concurrent  modifyTable or add/delete/modify columnFamily leads to incorrect 
> result. After HBASE-18893, The behavior of add/delete/modify column family 
> during concurrent operation is changed compare to branch-1.When  one client 
> is adding cf2 and another one cf3 .. In branch-1 final result will be 
> cf1,cf2,cf3 but now either cf1,cf2 OR cf1,cf3 will be the outcome depending 
> on which ModifyTableProcedure executed finally.Its because new table 
> descriptor is constructed before submitting the ModifyTableProcedure in 
> HMaster class and its not guarded by any lock.
> *Steps to reproduce*
> 1.Create table 't' with column family 'f1'
> 2.Client-1 and Client-2 requests to add column family 'f2' and 'f3' on table 
> 't' concurrently.
> *Expected Result*
> Table should have three column families(f1,f2,f3)
> *Actual Result*
> Table 't' will have column family either (f1,f2) or (f1,f3)



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

Reply via email to