[hibernate-issues] [Hibernate-JIRA] Created: (HHH-3952) Enabling second level caching at runtime

[Galder Zamarreno (JIRA)]

Enabling second level caching at runtime
----------------------------------------

                 Key: HHH-3952
                 URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-3952
             Project: Hibernate Core
          Issue Type: New Feature
          Components: caching (L2)
            Reporter: Galder Zamarreno


To be able to extend rolling upgrade strategies such as the one explained in http://www.jboss.org/community/docs/DOC-10910 
to situations where 2nd level cache is used, some kind of dynamic switch for 2nd level cache would be required.

The requirement comes from the fact that while the old cluster is running, users could update entities in the 2nd level cache after
these entities have been read and loaded into the 2nd level cache in the new cluster. Since the old cluster and the new cluster
does not communicate directly, invalidation messages from the old cluster would not be received by the new cluster and hence, 
the new cluster could be interacting with stale data.

The most sensible thing here IMO would be to start the new cluster with 2nd level cache disabled and at some point, when the old
cluster has been completely shut down, turn it on again. This would require exposing some kind of control to be able to do the 
switch. for example via JMX.

-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators: http://opensource.atlassian.com/projects/hibernate/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira