Author: manik.surtani(a)jboss.com Date: 2008-07-11 13:01:51 -0400 (Fri, 11 Jul 2008) New Revision: 6251 Modified: core/trunk/src/main/java/org/jboss/cache/NodeFactory.java core/trunk/src/main/java/org/jboss/cache/mvcc/ReadCommittedNode.java core/trunk/src/main/java/org/jboss/cache/mvcc/RepeatableReadNode.java Log: Do we actualy need data versions with MVCC? Modified: core/trunk/src/main/java/org/jboss/cache/NodeFactory.java =================================================================== --- core/trunk/src/main/java/org/jboss/cache/NodeFactory.java 2008-07-11 15:46:23 UTC (rev 6250) +++ core/trunk/src/main/java/org/jboss/cache/NodeFactory.java 2008-07-11 17:01:51 UTC (rev 6251) @@ -125,6 +125,7 @@ */ public NodeSPI<K, V> createDataNode(Object childName, Fqn fqn, NodeSPI<K, V> parent, Map<K, V> data, boolean mapSafe) { + // TODO: See if data versions are needed with MVCC. Should use cheaper UnversionedNode otherwise. UnversionedNode un = useVersionedNode ? new VersionedNode<K, V>(fqn, parent, data, cache) : new UnversionedNode<K, V>(childName, fqn, data, cache); // it is internal nodes that are wrapped in NIDs. Modified: core/trunk/src/main/java/org/jboss/cache/mvcc/ReadCommittedNode.java =================================================================== --- core/trunk/src/main/java/org/jboss/cache/mvcc/ReadCommittedNode.java 2008-07-11 15:46:23 UTC (rev 6250) +++ core/trunk/src/main/java/org/jboss/cache/mvcc/ReadCommittedNode.java 2008-07-11 17:01:51 UTC (rev 6251) @@ -52,6 +52,7 @@ InternalNode backupDelegationTarget = ((NodeReference) backup).getDelegate(); node = backupDelegationTarget.copy(); } + // TODO: See if data versions are even needed in the first place!! // TODO: Make sure this works with custom versions as well! // DataVersion newVersion = ((DefaultDataVersion) node.getVersion()).increment(); // node.setVersion(newVersion); Modified: core/trunk/src/main/java/org/jboss/cache/mvcc/RepeatableReadNode.java =================================================================== --- core/trunk/src/main/java/org/jboss/cache/mvcc/RepeatableReadNode.java 2008-07-11 15:46:23 UTC (rev 6250) +++ core/trunk/src/main/java/org/jboss/cache/mvcc/RepeatableReadNode.java 2008-07-11 17:01:51 UTC (rev 6251) @@ -8,7 +8,6 @@ import org.jboss.cache.invocation.InvocationContext; import org.jboss.cache.optimistic.DataVersion; import org.jboss.cache.optimistic.DataVersioningException; -import org.jboss.cache.optimistic.DefaultDataVersion; /** * A node delegate that encapsulates repeatable read semantics when writes are initiated, committed or rolled back. @@ -36,9 +35,11 @@ // check for write skew. NodeSPI underlyingNode = container.peek(fqn, false, true); // even check for invalid nodes. we should check tombstones too. DataVersion underlyingNodeVersion = underlyingNode == null ? null : underlyingNode.getVersion(); - if (!allowWriteSkew && underlyingNode != null && !node.getVersion().equals(underlyingNodeVersion)) + // TODO: See if data versions are even needed in the first place!! + //if (!allowWriteSkew && underlyingNode != null && !node.getVersion().equals(underlyingNodeVersion)) + if (!allowWriteSkew && underlyingNode != null && underlyingNode != node) { - String errormsg = new StringBuilder().append("Detected write skew on Fqn [").append(fqn).append("]. Attempting to overwrite version ").append(node.getVersion()).append(" but current version has progressed to ").append(underlyingNodeVersion).toString(); + String errormsg = new StringBuilder().append("Detected write skew on Fqn [").append(fqn).append("]. Another process has changed the node since we last read it!").toString(); if (log.isWarnEnabled()) log.warn(errormsg + ". Unable to copy node for update."); throw new DataVersioningException(errormsg); } @@ -46,11 +47,11 @@ // make a backup copy backup = node; node = backup.copy(); - + // TODO: See if data versions are even needed in the first place!! // update version on copy // TODO: Make sure this works with custom versions as well! - DataVersion newVersion = ((DefaultDataVersion) node.getVersion()).increment(); - node.setVersion(newVersion); +// DataVersion newVersion = ((DefaultDataVersion) node.getVersion()).increment(); +// node.setVersion(newVersion); } @Override