[infinispan-issues] [JBoss JIRA] (ISPN-4091) Transactions and data should prefer to be sourced from a primay owner

[Erik Salter (JIRA)]

     [ https://issues.jboss.org/browse/ISPN-4091?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Erik Salter updated ISPN-4091:
------------------------------

    Description: 
The current state transfer mechanism will ask the backup segments for transaction and state information.  However, this breaks if there is a pessimistic transaction executing on the primary data owner,  Consider the following use case:

A new owner joins and sources the ongoing transactions and data for key k from the backup.  Meanwhile, a local transaction has started on the primary owner for k, but has not prepared on any remote nodes.  So the new node does not know about the ongoing transaction.  While that's going on, a new tx starts on the new owner.  Since these are pessimistic, the new transaction will acquires the lock for the same key.  

So we can have data inconsistency.

The state transfer mechanism should prefer to source the transaction and state information from the primary owner.  This should cover all cases: if the originator is not the primary owner, then any (backup) locks must be replicated to all the owners, either directly during the tx or during a previous state transfer. 

  was:
The current state transfer mechanism will ask the backup segments for transaction and state information.  However, this breaks if there is a pessimistic transaction executing on the primary data owner,  Consider the following use case:

A new owner joins and sources the ongoing transactions and data for key k from the backup.  Meanwhile, a local transaction has started on the primary owner for k, but has not prepared on any remote nodes.  So the new node does not know about the ongoing transaction.  While that's going on, a new tx starts on the new owner.  Since these are pessimistic, the new transaction will acquires the lock for the same key.  

So we can have data inconsistency.

The state transfer mechanism should prefer to source the transaction and state information from the primary owner.  This should cover all cases: if the originator is not the primary owner, then any (backup) locks must be replicated to all the owners, either directly during the tx or during a previous state transfer. 


[13:26] <dberindei> I think asking the primary owner should be enough



    
> Transactions and data should prefer to be sourced from a primay owner
> ---------------------------------------------------------------------
>
>                 Key: ISPN-4091
>                 URL: https://issues.jboss.org/browse/ISPN-4091
>             Project: Infinispan
>          Issue Type: Bug
>          Components: State Transfer
>    Affects Versions: 5.2.7.Final
>            Reporter: Erik Salter
>            Assignee: Dan Berindei
>
> The current state transfer mechanism will ask the backup segments for transaction and state information.  However, this breaks if there is a pessimistic transaction executing on the primary data owner,  Consider the following use case:
> A new owner joins and sources the ongoing transactions and data for key k from the backup.  Meanwhile, a local transaction has started on the primary owner for k, but has not prepared on any remote nodes.  So the new node does not know about the ongoing transaction.  While that's going on, a new tx starts on the new owner.  Since these are pessimistic, the new transaction will acquires the lock for the same key.  
> So we can have data inconsistency.
> The state transfer mechanism should prefer to source the transaction and state information from the primary owner.  This should cover all cases: if the originator is not the primary owner, then any (backup) locks must be replicated to all the owners, either directly during the tx or during a previous state transfer. 

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira