1 Reply Latest reply on Jun 22, 2009 4:38 AM by mircea.markus

    Dirty read even though configured as REPEATABLE_READ or READ

    vishwasoft
    vishwasoft Jun 19, 2009 6:09 PM

      I'm trying to evaluate the JBossCache for our application
      I'm getting dirty read even though I rollback transaction. I tried this with EJB3 Stateless session bean BMT.

      Could you please anyone help me on this problem, Am I making anything wrong? please let me know if you need additional info

      JBosscache : jbosscache-core-3.1.0.GA
      JBoss As: jboss-5.0.0.GA
      JDK: 1.5.0_07


      Here is the code

      public class TestEntity {

 private int array[] = new int[100000];

 public void update(int value) {

 for (int i = 0; i < array.length; i++) {
 array [ i ]=value;
 }

 }

 public int[] getArray() {
 return array;
 }
}


      Stateless Bean1 code to modify cache

      Stateless Bean 1 
       public void updateArray(int value) {
 TransactionManager tm = cache.getConfiguration().getRuntimeConfig().getTransactionManager();
 try {
 tm.begin();
 String key = node.getFqn().toString();
 TestEntity t = (TestEntity) node.get(key);
 if(t != null) {
 t.update(value);
 node.put(key, t);
 }
 tm.rollback();
 } catch (Exception e) {
 try {
 tm.rollback();
 }catch(Exception ex1) {
 ex1.printStackTrace();
 }
 e.printStackTrace();
 }
 }


      Stateless Bean 2 to read and validating array 
       public boolean validateArray() {
 TransactionManager tm = cache.getConfiguration().getRuntimeConfig().getTransactionManager();
 try {
 tm.begin();
 int a[] = readArray();
 int value = a[0];
 for (int i = 0; i < a.length; i++) {
 if(a != value) {
 System.out.println(a+":"+value);
 sctx.getUserTransaction().rollback();
 return false;
 }
 }
 tm.commit();
 }catch(Exception ex) {
 try {
 tm.rollback();
 }catch(Exception ex1) {
 ex1.printStackTrace();
 }
 ex.printStackTrace();
 }
 return true;
 }

      Configuration file:
      I have used configuration file example for cache configuration 
      <locking isolationLevel="REPEATABLE_READ"
 lockParentForChildInsertRemove="false" lockAcquisitionTimeout="50000"
 nodeLockingScheme="mvcc" writeSkewCheck="true" concurrencyLevel="500"
 useLockStriping="false" />

 <transaction transactionManagerLookupClass="org.jboss.cache.transaction.DummyTransactionManagerLookup"
 syncRollbackPhase="true" syncCommitPhase="true" />

<?xml version="1.0" encoding="UTF-8"?>

<jbosscache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xmlns="urn:jboss:jbosscache-core:config:3.1">
 <locking isolationLevel="REPEATABLE_READ"
 lockParentForChildInsertRemove="false" lockAcquisitionTimeout="50000"
 nodeLockingScheme="mvcc" writeSkewCheck="true" concurrencyLevel="500"
 useLockStriping="false" />

 <transaction transactionManagerLookupClass="org.jboss.cache.transaction.DummyTransactionManagerLookup"
 syncRollbackPhase="true" syncCommitPhase="true" />

 <jmxStatistics enabled="true" />

 <shutdown hookBehavior="REGISTER" />

 <listeners asyncPoolSize="1" asyncQueueSize="1000000" />

 <serialization objectInputStreamPoolSize="50"
 objectOutputStreamPoolSize="50" version="3.0.0"
 marshallerClass="org.jboss.cache.marshall.VersionAwareMarshaller"
 useLazyDeserialization="false" useRegionBasedMarshalling="false" />

 <loaders passivation="true" shared="false">
 <preload>
 <node fqn="/" />
 </preload>
 <loader class="org.jboss.cache.loader.bdbje.BdbjeCacheLoader" async="false"
 fetchPersistentState="true" ignoreModifications="false"
 purgeOnStartup="false">
 <properties>location=c:/JavaTools/tmp</properties>
 </loader>
 </loaders>
</jbosscache>


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