MVCC lock timeout exception after 0? ms.

[zeravlai]

Hi all,

I'm using jboss cache 3.0.2 and have a cache configured with MVCC. The cache is being used by hibernate as a second level cache, in a 2 nodes cluster using INVALIDATION_SYNC.

I have also configured the lockAcquisitionTimeout to 15000.

The thing is I see exceptions like this:

 [exec] 17:50:17,890 INFO [STDOUT] Caused by: org.jboss.cache.lock.TimeoutException: Unable to acquire lock on Fqn [/persistence.unit:unitName=SPECjAppServer.ear/corp.jar#corp-persistence/org/spec/jappserver/corp/customerinventoryent/ejb/CCustomerInventory/ENTITY/org.spec.jappserver.corp.customerinventoryent.ejb.CCustomerInventory#394737] after [0] milliseconds for requestor [Thread[Incoming-11,138.100.12.127:60763,10,Thread Pools]]! Lock held by [GlobalTransaction:<138.100.12.127:60763>:18482]
 [exec] 17:50:17,891 INFO [STDOUT] at org.jboss.cache.mvcc.MVCCNodeHelper.acquireLock(MVCCNodeHelper.java:170)

where I can read the cache is unable to get a lock after 0 milliseconds.

Is there any other parameter that takes care of the timeoutexception, rather than lockAcquisitionTimeout?

Thanks a lot !!

[zeravlai]

I just made the same test with REPL_SYNC and I can see the same exception with the right lockAcquisitionTimeout (15000).

Is REPL or INVALIDATION what makes the difference here?

[galder.zamarreno]

Those lock timeouts with 0ms timeout are not important. These timeouts come when reading an entity from database into the 2nd level cache and it puts it with a timeout of 0ms, so if succeeds, great, if not, it's ignored (someone else might be putting the same entity in the database).