"Unable to acquire lock on Fqn" exception with clustered Pojocache

[brettcave]

When using pojocache in a clustered environment, the attach method throws an exception.

JBoss AS 5.1.0.GA, with pojocache 3.0 and jboss cache 3.1 (casabel).

The attach method works fine in a non-clustered environment, but the moment a second JBoss node is added to the partition, with the pojocache service deployed, any attach calls throw the exception below:

Caused by: org.jboss.cache.pojo.PojoCacheException: attach failed /rules/9ec2c1bb-e37f-4592-9348-953dc164ed04
        at org.jboss.cache.pojo.impl.PojoCacheImpl.attach(PojoCacheImpl.java:111)
        at org.jboss.cache.pojo.impl.PojoCacheImpl.attach(PojoCacheImpl.java:93)
        at org.jboss.cache.pojo.impl.PojoCacheImpl.attach(PojoCacheImpl.java:88)
        at com.mycompany.system.session.PojoCacheManagerBean.writeToCache(PojoCacheManagerBean.java:39)
        ... 246 more
Caused by: org.jboss.cache.lock.TimeoutException: Unable to acquire lock on Fqn [/rules] after [10000] milliseconds for requestor [GlobalTransaction:<192.168.75.12:46555>:3468]! Lock held by [GlobalTransaction:<192.168.75.12:46555>:3469]
        at org.jboss.cache.mvcc.MVCCNodeHelper.acquireLock(MVCCNodeHelper.java:157)
        at org.jboss.cache.mvcc.MVCCNodeHelper.wrapNodeForWriting(MVCCNodeHelper.java:235)
        at org.jboss.cache.mvcc.MVCCNodeHelper.wrapNodeForWriting(MVCCNodeHelper.java:184)
        at org.jboss.cache.mvcc.MVCCNodeHelper.wrapNodeForWriting(MVCCNodeHelper.java:225)
        at org.jboss.cache.mvcc.MVCCNodeHelper.wrapNodeForWriting(MVCCNodeHelper.java:184)

com.mycompany.system.session.PojoCacheManagerBean.writeToCache:

public void writeToCache(Object ob, String path) {
    ObjectName on = new ObjectName("jboss.cache:service=PojoCache");
   
PojoCache cache = (PojoCacheJmxWrapperMBean)
MBeanServerInvocationHandler.newProxyInstance(MBeanServerLocator.locateJBoss(),
on, PojoCacheJmxWrapperMBean.class, false).getPojoCache;
    cache.attach(ob,path);
}

[brettcave]

<server>
   <mbean code="org.jboss.cache.pojo.jmx.PojoCacheJmxWrapper" name="jboss.cache:service=PojoCache">
      <depends>jboss:service=TransactionManager</depends>
      <attribute name="TransactionManagerLookupClass">org.jboss.cache.transaction.JBossTransactionManagerLookup</attribute>
      <attribute name="IsolationLevel">REPEATABLE_READ</attribute>
      <attribute name="CacheMode">REPL_SYNC</attribute>
      <attribute name="ClusterName">PojoCache-${jboss.partition.name:DefaultPartition}</attribute>
      <attribute name="ClusterConfig">
         <config>
            <UDP mcast_addr="228.1.2.3" mcast_port="48866"
                 ip_ttl="64" ip_mcast="true"
                 mcast_send_buf_size="150000" mcast_recv_buf_size="80000"
                 ucast_send_buf_size="150000" ucast_recv_buf_size="80000"
                 loopback="false"/>
            <PING timeout="2000" num_initial_members="3"/>
            <MERGE2 min_interval="10000" max_interval="20000"/>
            <FD shun="true"/>
            <FD_SOCK/>
            <VERIFY_SUSPECT timeout="1500"/>
            <pbcast.NAKACK gc_lag="50" retransmit_timeout="600,1200,2400,4800" />
            <UNICAST timeout="600,1200,2400,4800" />
            <pbcast.STABLE desired_avg_gossip="400000"/>
            <FC max_credits="2000000" min_threshold="0.10"/>
            <FRAG2 frag_size="8192"/>
            <pbcast.GMS join_timeout="5000" shun="true" print_local_addr="true"/>
            <pbcast.STATE_TRANSFER/>
         </config>
      </attribute>
      <attribute name="FetchInMemoryState">true</attribute>
      <attribute name="InitialStateRetrievalTimeout">15000</attribute>
      <attribute name="SyncReplTimeout">15000</attribute>
      <attribute name="LockAcquisitionTimeout">10000</attribute>
   </mbean>
</server>

[brettcave]

Seems to be caused by a bug:

https://jira.jboss.org/jira/browse/JBCACHE-1565

1. configure pojocache using JBossTransactionManager and run in a clustered environment

2. attach an object to the cache.

Exception about not being able to acquire lock on Fqn is thrown.