diff --git a/hyracks/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/BufferCache.java b/hyracks/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/BufferCache.java
index 2992dfe..ac722e2 100644
--- a/hyracks/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/BufferCache.java
+++ b/hyracks/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/BufferCache.java
@@ -477,9 +477,14 @@
         private void acquireWriteLatch(boolean markDirty) {
             latch.writeLock().lock();
             if (markDirty) {
-                if (dirty.compareAndSet(false, true)) {
-                    pinCount.incrementAndGet();
-                }
+                markDirty();
+            }
+        }
+
+        @Override
+        public void markDirty() {
+            if (dirty.compareAndSet(false, true)) {
+                pinCount.incrementAndGet();
             }
         }
 
diff --git a/hyracks/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/ICachedPageInternal.java b/hyracks/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/ICachedPageInternal.java
index 22c02d1..b2ba638 100644
--- a/hyracks/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/ICachedPageInternal.java
+++ b/hyracks/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/ICachedPageInternal.java
@@ -20,4 +20,6 @@
     public Object getReplacementStrategyObject();
 
     public boolean pinIfGoodVictim();
+
+    public void markDirty();
 }
\ No newline at end of file
diff --git a/pregelix/pregelix-core/src/main/java/edu/uci/ics/pregelix/core/jobgen/JobGenOuterJoin.java b/pregelix/pregelix-core/src/main/java/edu/uci/ics/pregelix/core/jobgen/JobGenOuterJoin.java
index 2e83d2d..fcbf9f2 100644
--- a/pregelix/pregelix-core/src/main/java/edu/uci/ics/pregelix/core/jobgen/JobGenOuterJoin.java
+++ b/pregelix/pregelix-core/src/main/java/edu/uci/ics/pregelix/core/jobgen/JobGenOuterJoin.java
@@ -17,7 +17,6 @@
 import org.apache.hadoop.io.VLongWritable;
 import org.apache.hadoop.io.Writable;
 import org.apache.hadoop.io.WritableComparable;
-import org.apache.hadoop.io.WritableComparator;
 
 import edu.uci.ics.hyracks.api.constraints.PartitionConstraintHelper;
 import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
diff --git a/pregelix/pregelix-dataflow-std-base/pom.xml b/pregelix/pregelix-dataflow-std-base/pom.xml
index d4c0ee6..2b435a1 100644
--- a/pregelix/pregelix-dataflow-std-base/pom.xml
+++ b/pregelix/pregelix-dataflow-std-base/pom.xml
@@ -1,28 +1,24 @@
-<!--
- ! Copyright 2009-2013 by The Regents of the University of California
- ! Licensed under the Apache License, Version 2.0 (the "License");
- ! you may not use this file except in compliance with the License.
- ! you may obtain a copy of the License from
- ! 
- !     http://www.apache.org/licenses/LICENSE-2.0
- ! 
- ! Unless required by applicable law or agreed to in writing, software
- ! distributed under the License is distributed on an "AS IS" BASIS,
- ! WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- ! See the License for the specific language governing permissions and
- ! limitations under the License.
- !-->
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+<!-- ! Copyright 2009-2013 by The Regents of the University of California 
+	! Licensed under the Apache License, Version 2.0 (the "License"); ! you may 
+	not use this file except in compliance with the License. ! you may obtain 
+	a copy of the License from ! ! http://www.apache.org/licenses/LICENSE-2.0 
+	! ! Unless required by applicable law or agreed to in writing, software ! 
+	distributed under the License is distributed on an "AS IS" BASIS, ! WITHOUT 
+	WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. ! See the 
+	License for the specific language governing permissions and ! limitations 
+	under the License. ! -->
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 	<artifactId>pregelix-dataflow-std-base</artifactId>
 	<packaging>jar</packaging>
 	<name>pregelix-dataflow-std-base</name>
 
 	<parent>
-    		<groupId>edu.uci.ics.hyracks</groupId>
-    		<artifactId>pregelix</artifactId>
-    		<version>0.2.10-SNAPSHOT</version>
-  	</parent>
+		<groupId>edu.uci.ics.hyracks</groupId>
+		<artifactId>pregelix</artifactId>
+		<version>0.2.10-SNAPSHOT</version>
+	</parent>
 
 
 	<properties>
@@ -58,7 +54,7 @@
 			<plugin>
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-clean-plugin</artifactId>
-                <version>2.4.1</version>
+				<version>2.4.1</version>
 				<configuration>
 					<filesets>
 						<fileset>
@@ -94,6 +90,13 @@
 		</dependency>
 		<dependency>
 			<groupId>edu.uci.ics.hyracks</groupId>
+			<artifactId>hyracks-storage-am-common</artifactId>
+			<version>0.2.10-SNAPSHOT</version>
+			<type>jar</type>
+			<scope>compile</scope>
+		</dependency>
+		<dependency>
+			<groupId>edu.uci.ics.hyracks</groupId>
 			<artifactId>hyracks-api</artifactId>
 			<version>0.2.10-SNAPSHOT</version>
 			<type>jar</type>
diff --git a/pregelix/pregelix-dataflow-std-base/src/main/java/edu/uci/ics/pregelix/dataflow/std/base/IUpdateFunction.java b/pregelix/pregelix-dataflow-std-base/src/main/java/edu/uci/ics/pregelix/dataflow/std/base/IUpdateFunction.java
index b8ba7bd..081b3bc 100644
--- a/pregelix/pregelix-dataflow-std-base/src/main/java/edu/uci/ics/pregelix/dataflow/std/base/IUpdateFunction.java
+++ b/pregelix/pregelix-dataflow-std-base/src/main/java/edu/uci/ics/pregelix/dataflow/std/base/IUpdateFunction.java
@@ -18,17 +18,18 @@
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.IIndexCursor;
 
 public interface IUpdateFunction extends IFunction {
 
-	/**
-	 * update the tuple pointed by tupleRef called after process,
-	 * one-input-tuple-at-a-time
-	 * 
-	 * @param tupleRef
-	 * @throws HyracksDataException
-	 */
-	public void update(ITupleReference tupleRef, ArrayTupleBuilder cloneUpdateTb)
-			throws HyracksDataException;
+    /**
+     * update the tuple pointed by tupleRef called after process,
+     * one-input-tuple-at-a-time
+     * 
+     * @param tupleRef
+     * @throws HyracksDataException
+     */
+    public void update(ITupleReference tupleRef, ArrayTupleBuilder cloneUpdateTb, IIndexCursor cursor)
+            throws HyracksDataException;
 
 }
diff --git a/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopJoinFunctionUpdateOperatorNodePushable.java b/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopJoinFunctionUpdateOperatorNodePushable.java
index 2332188..b646661 100644
--- a/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopJoinFunctionUpdateOperatorNodePushable.java
+++ b/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopJoinFunctionUpdateOperatorNodePushable.java
@@ -34,6 +34,7 @@
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.AbstractTreeIndexOperatorDescriptor;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexDataflowHelper;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexDataflowHelper;
 import edu.uci.ics.hyracks.storage.am.common.impls.NoOpOperationCallback;
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 import edu.uci.ics.hyracks.storage.am.common.tuples.PermutingFrameTupleReference;
@@ -43,6 +44,7 @@
 import edu.uci.ics.pregelix.dataflow.util.CopyUpdateUtil;
 import edu.uci.ics.pregelix.dataflow.util.FunctionProxy;
 import edu.uci.ics.pregelix.dataflow.util.SearchKeyTupleReference;
+import edu.uci.ics.pregelix.dataflow.util.StorageType;
 import edu.uci.ics.pregelix.dataflow.util.UpdateBuffer;
 
 public class IndexNestedLoopJoinFunctionUpdateOperatorNodePushable extends AbstractUnaryInputOperatorNodePushable {
@@ -68,6 +70,7 @@
     private ArrayTupleBuilder cloneUpdateTb;
     private final UpdateBuffer updateBuffer;
     private final SearchKeyTupleReference tempTupleReference = new SearchKeyTupleReference();
+    private final StorageType storageType;
 
     public IndexNestedLoopJoinFunctionUpdateOperatorNodePushable(AbstractTreeIndexOperatorDescriptor opDesc,
             IHyracksTaskContext ctx, int partition, IRecordDescriptorProvider recordDescProvider, boolean isForward,
@@ -77,6 +80,11 @@
             throws HyracksDataException {
         treeIndexOpHelper = (IndexDataflowHelper) opDesc.getIndexDataflowHelperFactory().createIndexDataflowHelper(
                 opDesc, ctx, partition);
+        if (treeIndexOpHelper instanceof TreeIndexDataflowHelper) {
+            storageType = StorageType.TreeIndex;
+        } else {
+            storageType = StorageType.LSMIndex;
+        }
         this.lowKeyInclusive = lowKeyInclusive;
         this.highKeyInclusive = highKeyInclusive;
         this.recDesc = recordDescProvider.getInputRecordDescriptor(opDesc.getActivityId(), 0);
@@ -170,13 +178,13 @@
             /**
              * call the update function
              */
-            functionProxy.functionCall(leftAccessor, tIndex, indexEntryTuple, cloneUpdateTb);
+            functionProxy.functionCall(leftAccessor, tIndex, indexEntryTuple, cloneUpdateTb, cursor);
 
             /**
              * doing copy update
              */
             CopyUpdateUtil.copyUpdate(tempTupleReference, indexEntryTuple, updateBuffer, cloneUpdateTb, indexAccessor,
-                    cursor, rangePred, false);
+                    cursor, rangePred, false, storageType);
         }
     }
 
diff --git a/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopRightOuterJoinFunctionUpdateOperatorNodePushable.java b/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopRightOuterJoinFunctionUpdateOperatorNodePushable.java
index 3a36ab4..2557a07 100644
--- a/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopRightOuterJoinFunctionUpdateOperatorNodePushable.java
+++ b/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopRightOuterJoinFunctionUpdateOperatorNodePushable.java
@@ -36,6 +36,7 @@
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.AbstractTreeIndexOperatorDescriptor;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexDataflowHelper;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexDataflowHelper;
 import edu.uci.ics.hyracks.storage.am.common.impls.NoOpOperationCallback;
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 import edu.uci.ics.hyracks.storage.am.common.tuples.PermutingFrameTupleReference;
@@ -45,6 +46,7 @@
 import edu.uci.ics.pregelix.dataflow.util.CopyUpdateUtil;
 import edu.uci.ics.pregelix.dataflow.util.FunctionProxy;
 import edu.uci.ics.pregelix.dataflow.util.SearchKeyTupleReference;
+import edu.uci.ics.pregelix.dataflow.util.StorageType;
 import edu.uci.ics.pregelix.dataflow.util.UpdateBuffer;
 
 public class IndexNestedLoopRightOuterJoinFunctionUpdateOperatorNodePushable extends
@@ -79,6 +81,7 @@
     private ArrayTupleBuilder cloneUpdateTb;
     private final UpdateBuffer updateBuffer;
     private final SearchKeyTupleReference tempTupleReference = new SearchKeyTupleReference();
+    private final StorageType storageType;
 
     public IndexNestedLoopRightOuterJoinFunctionUpdateOperatorNodePushable(AbstractTreeIndexOperatorDescriptor opDesc,
             IHyracksTaskContext ctx, int partition, IRecordDescriptorProvider recordDescProvider, boolean isForward,
@@ -88,6 +91,11 @@
         inputRecDesc = recordDescProvider.getInputRecordDescriptor(opDesc.getActivityId(), 0);
         treeIndexOpHelper = (IndexDataflowHelper) opDesc.getIndexDataflowHelperFactory().createIndexDataflowHelper(
                 opDesc, ctx, partition);
+        if (treeIndexOpHelper instanceof TreeIndexDataflowHelper) {
+            storageType = StorageType.TreeIndex;
+        } else {
+            storageType = StorageType.LSMIndex;
+        }
         this.recDesc = recordDescProvider.getInputRecordDescriptor(opDesc.getActivityId(), 0);
 
         if (lowKeyFields != null && lowKeyFields.length > 0) {
@@ -287,13 +295,13 @@
         /**
          * function call
          */
-        functionProxy.functionCall(leftAccessor, tIndex, indexEntryTuple, cloneUpdateTb);
+        functionProxy.functionCall(leftAccessor, tIndex, indexEntryTuple, cloneUpdateTb, cursor);
 
         /**
          * doing clone update
          */
         CopyUpdateUtil.copyUpdate(tempTupleReference, indexEntryTuple, updateBuffer, cloneUpdateTb, indexAccessor,
-                cursor, rangePred, true);
+                cursor, rangePred, true, storageType);
     }
 
     /** write result for outer case */
@@ -301,11 +309,11 @@
         /**
          * function call
          */
-        functionProxy.functionCall(nullTupleBuilder, frameTuple, cloneUpdateTb);
+        functionProxy.functionCall(nullTupleBuilder, frameTuple, cloneUpdateTb, cursor);
 
         //doing clone update
         CopyUpdateUtil.copyUpdate(tempTupleReference, frameTuple, updateBuffer, cloneUpdateTb, indexAccessor, cursor,
-                rangePred, true);
+                rangePred, true, storageType);
     }
 
     @Override
diff --git a/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopSetUnionFunctionUpdateOperatorNodePushable.java b/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopSetUnionFunctionUpdateOperatorNodePushable.java
index 8d97289..1d9fd70 100644
--- a/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopSetUnionFunctionUpdateOperatorNodePushable.java
+++ b/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopSetUnionFunctionUpdateOperatorNodePushable.java
@@ -34,6 +34,7 @@
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.AbstractTreeIndexOperatorDescriptor;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexDataflowHelper;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexDataflowHelper;
 import edu.uci.ics.hyracks.storage.am.common.impls.NoOpOperationCallback;
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 import edu.uci.ics.hyracks.storage.am.common.tuples.PermutingFrameTupleReference;
@@ -43,6 +44,7 @@
 import edu.uci.ics.pregelix.dataflow.util.CopyUpdateUtil;
 import edu.uci.ics.pregelix.dataflow.util.FunctionProxy;
 import edu.uci.ics.pregelix.dataflow.util.SearchKeyTupleReference;
+import edu.uci.ics.pregelix.dataflow.util.StorageType;
 import edu.uci.ics.pregelix.dataflow.util.UpdateBuffer;
 
 public class IndexNestedLoopSetUnionFunctionUpdateOperatorNodePushable extends AbstractUnaryInputOperatorNodePushable {
@@ -71,6 +73,7 @@
     private ArrayTupleBuilder cloneUpdateTb;
     private UpdateBuffer updateBuffer;
     private final SearchKeyTupleReference tempTupleReference = new SearchKeyTupleReference();
+    private final StorageType storageType;
 
     public IndexNestedLoopSetUnionFunctionUpdateOperatorNodePushable(AbstractTreeIndexOperatorDescriptor opDesc,
             IHyracksTaskContext ctx, int partition, IRecordDescriptorProvider recordDescProvider, boolean isForward,
@@ -79,6 +82,11 @@
             IRecordDescriptorFactory inputRdFactory, int outputArity) throws HyracksDataException {
         treeIndexOpHelper = (IndexDataflowHelper) opDesc.getIndexDataflowHelperFactory().createIndexDataflowHelper(
                 opDesc, ctx, partition);
+        if (treeIndexOpHelper instanceof TreeIndexDataflowHelper) {
+            storageType = StorageType.TreeIndex;
+        } else {
+            storageType = StorageType.LSMIndex;
+        }
         this.isForward = isForward;
         this.recDesc = recordDescProvider.getInputRecordDescriptor(opDesc.getActivityId(), 0);
 
@@ -238,21 +246,21 @@
 
     /** write the right result */
     private void writeRightResults(ITupleReference frameTuple) throws Exception {
-        functionProxy.functionCall(frameTuple, cloneUpdateTb);
+        functionProxy.functionCall(frameTuple, cloneUpdateTb, cursor);
 
         //doing clone update
         CopyUpdateUtil.copyUpdate(tempTupleReference, frameTuple, updateBuffer, cloneUpdateTb, indexAccessor, cursor,
-                rangePred, true);
+                rangePred, true, storageType);
     }
 
     /** write the left result */
     private void writeLeftResults(IFrameTupleAccessor leftAccessor, int tIndex, ITupleReference frameTuple)
             throws Exception {
-        functionProxy.functionCall(leftAccessor, tIndex, frameTuple, cloneUpdateTb);
+        functionProxy.functionCall(leftAccessor, tIndex, frameTuple, cloneUpdateTb, cursor);
 
         //doing clone update
         CopyUpdateUtil.copyUpdate(tempTupleReference, frameTuple, updateBuffer, cloneUpdateTb, indexAccessor, cursor,
-                rangePred, true);
+                rangePred, true, storageType);
     }
 
     @Override
diff --git a/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/TreeSearchFunctionUpdateOperatorNodePushable.java b/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/TreeSearchFunctionUpdateOperatorNodePushable.java
index dbdbfa2..1003431 100644
--- a/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/TreeSearchFunctionUpdateOperatorNodePushable.java
+++ b/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/TreeSearchFunctionUpdateOperatorNodePushable.java
@@ -35,6 +35,7 @@
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.AbstractTreeIndexOperatorDescriptor;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexDataflowHelper;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexDataflowHelper;
 import edu.uci.ics.hyracks.storage.am.common.impls.NoOpOperationCallback;
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 import edu.uci.ics.hyracks.storage.am.common.tuples.PermutingFrameTupleReference;
@@ -44,6 +45,7 @@
 import edu.uci.ics.pregelix.dataflow.util.CopyUpdateUtil;
 import edu.uci.ics.pregelix.dataflow.util.FunctionProxy;
 import edu.uci.ics.pregelix.dataflow.util.SearchKeyTupleReference;
+import edu.uci.ics.pregelix.dataflow.util.StorageType;
 import edu.uci.ics.pregelix.dataflow.util.UpdateBuffer;
 
 public class TreeSearchFunctionUpdateOperatorNodePushable extends AbstractUnaryInputOperatorNodePushable {
@@ -77,6 +79,7 @@
     private ArrayTupleBuilder cloneUpdateTb;
     private final UpdateBuffer updateBuffer;
     private final SearchKeyTupleReference tempTupleReference = new SearchKeyTupleReference();
+    private final StorageType storageType;
 
     public TreeSearchFunctionUpdateOperatorNodePushable(AbstractTreeIndexOperatorDescriptor opDesc,
             IHyracksTaskContext ctx, int partition, IRecordDescriptorProvider recordDescProvider, boolean isForward,
@@ -86,6 +89,11 @@
             throws HyracksDataException {
         treeIndexHelper = (IndexDataflowHelper) opDesc.getIndexDataflowHelperFactory().createIndexDataflowHelper(
                 opDesc, ctx, partition);
+        if (treeIndexHelper instanceof TreeIndexDataflowHelper) {
+            storageType = StorageType.TreeIndex;
+        } else {
+            storageType = StorageType.LSMIndex;
+        }
         this.isForward = isForward;
         this.lowKeyInclusive = lowKeyInclusive;
         this.highKeyInclusive = highKeyInclusive;
@@ -171,11 +179,11 @@
         while (cursor.hasNext()) {
             cursor.next();
             ITupleReference tuple = cursor.getTuple();
-            functionProxy.functionCall(tuple, cloneUpdateTb);
+            functionProxy.functionCall(tuple, cloneUpdateTb, cursor);
 
             //doing clone update
             CopyUpdateUtil.copyUpdate(tempTupleReference, tuple, updateBuffer, cloneUpdateTb, indexAccessor, cursor,
-                    rangePred, true);
+                    rangePred, true, storageType);
         }
     }
 
diff --git a/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/util/CopyUpdateUtil.java b/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/util/CopyUpdateUtil.java
index d2478ea..58ec8ab 100644
--- a/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/util/CopyUpdateUtil.java
+++ b/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/util/CopyUpdateUtil.java
@@ -18,27 +18,36 @@
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeRangeSearchCursor;
 import edu.uci.ics.hyracks.storage.am.btree.impls.RangePredicate;
 import edu.uci.ics.hyracks.storage.am.common.api.IIndexAccessor;
 import edu.uci.ics.hyracks.storage.am.common.api.IIndexCursor;
 import edu.uci.ics.hyracks.storage.am.common.api.IndexException;
+import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPageInternal;
 
 public class CopyUpdateUtil {
 
     public static void copyUpdate(SearchKeyTupleReference tempTupleReference, ITupleReference frameTuple,
             UpdateBuffer updateBuffer, ArrayTupleBuilder cloneUpdateTb, IIndexAccessor indexAccessor,
-            IIndexCursor cursor, RangePredicate rangePred, boolean scan) throws HyracksDataException, IndexException {
+            IIndexCursor cursor, RangePredicate rangePred, boolean scan, StorageType type) throws HyracksDataException,
+            IndexException {
         if (cloneUpdateTb.getSize() > 0) {
-            int[] fieldEndOffsets = cloneUpdateTb.getFieldEndOffsets();
-            int srcStart = fieldEndOffsets[0];
-            int srcLen = fieldEndOffsets[1] - fieldEndOffsets[0]; // the updated vertex size
-            int frSize = frameTuple.getFieldLength(1); // the vertex binary size in the leaf page
-            if (srcLen == frSize) {
-                //doing in-place update if the vertex size is not larger than the original size, save the "real update" overhead
-                System.arraycopy(cloneUpdateTb.getByteArray(), srcStart, frameTuple.getFieldData(1),
-                        frameTuple.getFieldStart(1), srcLen);
-                cloneUpdateTb.reset();
-                return;
+            if (type == StorageType.TreeIndex) {
+                int[] fieldEndOffsets = cloneUpdateTb.getFieldEndOffsets();
+                int srcStart = fieldEndOffsets[0];
+                int srcLen = fieldEndOffsets[1] - fieldEndOffsets[0]; // the updated vertex size
+                int frSize = frameTuple.getFieldLength(1); // the vertex binary size in the leaf page
+                if (srcLen == frSize) {
+                    System.arraycopy(cloneUpdateTb.getByteArray(), srcStart, frameTuple.getFieldData(1),
+                            frameTuple.getFieldStart(1), srcLen);
+                    cloneUpdateTb.reset();
+
+                    BTreeRangeSearchCursor btreeCursor = (BTreeRangeSearchCursor) cursor;
+                    ICachedPageInternal page = (ICachedPageInternal) btreeCursor.getPage();
+                    //IMPORTANT: mark the page to be dirty
+                    page.markDirty();
+                    return;
+                }
             }
             if (!updateBuffer.appendTuple(cloneUpdateTb)) {
                 tempTupleReference.reset(frameTuple.getFieldData(0), frameTuple.getFieldStart(0),
@@ -51,7 +60,7 @@
                 if (!updateBuffer.appendTuple(cloneUpdateTb)) {
                     throw new HyracksDataException("cannot append tuple builder!");
                 }
-                //search again and recover the cursor
+                //search again and recover the cursor to the exact point as the one before it is closed
                 cursor.reset();
                 rangePred.setLowKey(tempTupleReference, true);
                 if (scan) {
diff --git a/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/util/FunctionProxy.java b/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/util/FunctionProxy.java
index a1e5b86..e5bdb17 100644
--- a/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/util/FunctionProxy.java
+++ b/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/util/FunctionProxy.java
@@ -22,6 +22,7 @@
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.IIndexCursor;
 import edu.uci.ics.pregelix.dataflow.std.base.IRecordDescriptorFactory;
 import edu.uci.ics.pregelix.dataflow.std.base.IRuntimeHookFactory;
 import edu.uci.ics.pregelix.dataflow.std.base.IUpdateFunction;
@@ -80,10 +81,10 @@
      * @throws HyracksDataException
      */
     public void functionCall(IFrameTupleAccessor leftAccessor, int leftTupleIndex, ITupleReference right,
-            ArrayTupleBuilder cloneUpdateTb) throws HyracksDataException {
+            ArrayTupleBuilder cloneUpdateTb, IIndexCursor cursor) throws HyracksDataException {
         Object[] tuple = tupleDe.deserializeRecord(leftAccessor, leftTupleIndex, right);
         function.process(tuple);
-        function.update(right, cloneUpdateTb);
+        function.update(right, cloneUpdateTb, cursor);
     }
 
     /**
@@ -92,10 +93,11 @@
      * @param updateRef
      * @throws HyracksDataException
      */
-    public void functionCall(ITupleReference updateRef, ArrayTupleBuilder cloneUpdateTb) throws HyracksDataException {
+    public void functionCall(ITupleReference updateRef, ArrayTupleBuilder cloneUpdateTb, IIndexCursor cursor)
+            throws HyracksDataException {
         Object[] tuple = tupleDe.deserializeRecord(updateRef);
         function.process(tuple);
-        function.update(updateRef, cloneUpdateTb);
+        function.update(updateRef, cloneUpdateTb, cursor);
     }
 
     /**
@@ -107,11 +109,11 @@
      *            update pointer
      * @throws HyracksDataException
      */
-    public void functionCall(ArrayTupleBuilder tb, ITupleReference inPlaceUpdateRef, ArrayTupleBuilder cloneUpdateTb)
-            throws HyracksDataException {
+    public void functionCall(ArrayTupleBuilder tb, ITupleReference inPlaceUpdateRef, ArrayTupleBuilder cloneUpdateTb,
+            IIndexCursor cursor) throws HyracksDataException {
         Object[] tuple = tupleDe.deserializeRecord(tb, inPlaceUpdateRef);
         function.process(tuple);
-        function.update(inPlaceUpdateRef, cloneUpdateTb);
+        function.update(inPlaceUpdateRef, cloneUpdateTb, cursor);
     }
 
     /**
diff --git a/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/util/StorageType.java b/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/util/StorageType.java
new file mode 100644
index 0000000..fb2d1eb
--- /dev/null
+++ b/pregelix/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/util/StorageType.java
@@ -0,0 +1,21 @@
+/*
+ * Copyright 2009-2013 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.pregelix.dataflow.util;
+
+public enum StorageType {
+    TreeIndex,
+    LSMIndex
+}
diff --git a/pregelix/pregelix-example/src/test/java/edu/uci/ics/pregelix/example/UpdateVertex.java b/pregelix/pregelix-example/src/test/java/edu/uci/ics/pregelix/example/UpdateVertex.java
index e224617..1e6359d 100644
--- a/pregelix/pregelix-example/src/test/java/edu/uci/ics/pregelix/example/UpdateVertex.java
+++ b/pregelix/pregelix-example/src/test/java/edu/uci/ics/pregelix/example/UpdateVertex.java
@@ -15,6 +15,7 @@
 package edu.uci.ics.pregelix.example;
 
 import java.util.Iterator;
+import java.util.Random;
 
 import org.apache.hadoop.io.FloatWritable;
 import org.apache.hadoop.io.Text;
@@ -29,6 +30,7 @@
     private final int MAX_VALUE_SIZE = 32768 / 2;
     private VLongWritable msg = new VLongWritable();
     private Text tempValue = new Text();
+    private Random rand = new Random();
 
     @Override
     public void compute(Iterator<VLongWritable> msgIterator) throws Exception {
@@ -52,28 +54,52 @@
         int valueSize = getVertexValue().toString().toCharArray().length;
         long expectedValueSize = msgIterator.next().get();
         if (valueSize != expectedValueSize) {
-            throw new IllegalStateException("vertex id: " + getVertexId() + " vertex value size:" + valueSize
-                    + ", expected value size:" + expectedValueSize);
+            if (valueSize == -expectedValueSize) {
+                //verify fixed size update
+                char[] valueCharArray = getVertexValue().toString().toCharArray();
+                for (int i = 0; i < valueCharArray.length; i++) {
+                    if (valueCharArray[i] != 'b') {
+                        throw new IllegalStateException("vertex id: " + getVertexId()
+                                + " has a un-propagated update in the last iteration");
+                    }
+                }
+            } else {
+                throw new IllegalStateException("vertex id: " + getVertexId() + " vertex value size:" + valueSize
+                        + ", expected value size:" + expectedValueSize);
+            }
+        }
+        if (msgIterator.hasNext()) {
+            throw new IllegalStateException("more than one message for vertex " + " " + getVertexId() + " "
+                    + getVertexValue());
         }
     }
 
     private void updateAndSendMsg() {
-        int newValueSize = (int) Math.pow(Math.abs(getVertexId().get()), getSuperstep()) % MAX_VALUE_SIZE;
+        int newValueSize = rand.nextInt(MAX_VALUE_SIZE);
         char[] charArray = new char[newValueSize];
         for (int i = 0; i < charArray.length; i++) {
             charArray[i] = 'a';
         }
         /**
+         * set a self-message
+         */
+        msg.set(newValueSize);
+        boolean fixedSize = getVertexId().get() < 2000;
+        if (fixedSize) {
+            int oldSize = getVertexValue().toString().toCharArray().length;
+            charArray = new char[oldSize];
+            for (int i = 0; i < oldSize; i++) {
+                charArray[i] = 'b';
+            }
+            msg.set(-oldSize);
+        }
+
+        /**
          * set the vertex value
          */
         tempValue.set(new String(charArray));
         setVertexValue(tempValue);
 
-        /**
-         * send a self-message
-         */
-        msg.set(newValueSize);
-
         sendMsg(getVertexId(), msg);
         activate();
     }
diff --git a/pregelix/pregelix-runtime/pom.xml b/pregelix/pregelix-runtime/pom.xml
index 6564eb0..245c0f5 100644
--- a/pregelix/pregelix-runtime/pom.xml
+++ b/pregelix/pregelix-runtime/pom.xml
@@ -141,6 +141,13 @@
 		</dependency>
 		<dependency>
 			<groupId>edu.uci.ics.hyracks</groupId>
+			<artifactId>hyracks-storage-common</artifactId>
+			<version>0.2.10-SNAPSHOT</version>
+			<type>jar</type>
+			<scope>compile</scope>
+		</dependency>
+		<dependency>
+			<groupId>edu.uci.ics.hyracks</groupId>
 			<artifactId>hyracks-storage-am-btree</artifactId>
 			<version>0.2.10-SNAPSHOT</version>
 			<type>jar</type>
diff --git a/pregelix/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/ComputeUpdateFunctionFactory.java b/pregelix/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/ComputeUpdateFunctionFactory.java
index f3a0bb4..b1d1043 100644
--- a/pregelix/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/ComputeUpdateFunctionFactory.java
+++ b/pregelix/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/ComputeUpdateFunctionFactory.java
@@ -31,6 +31,9 @@
 import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
 import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeRangeSearchCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.IIndexCursor;
+import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPageInternal;
 import edu.uci.ics.pregelix.api.graph.GlobalAggregator;
 import edu.uci.ics.pregelix.api.graph.MsgList;
 import edu.uci.ics.pregelix.api.graph.Vertex;
@@ -110,7 +113,8 @@
             public void open(IHyracksTaskContext ctx, RecordDescriptor rd, IFrameWriter... writers)
                     throws HyracksDataException {
                 this.conf = confFactory.createConfiguration(ctx);
-                this.dynamicStateLength = BspUtils.getDynamicVertexValueSize(conf);
+                //LSM index does not have in-place update
+                this.dynamicStateLength = BspUtils.getDynamicVertexValueSize(conf) || BspUtils.useLSM(conf);
                 this.aggregator = BspUtils.createGlobalAggregator(conf);
                 this.aggregator.init();
 
@@ -262,7 +266,8 @@
             }
 
             @Override
-            public void update(ITupleReference tupleRef, ArrayTupleBuilder cloneUpdateTb) throws HyracksDataException {
+            public void update(ITupleReference tupleRef, ArrayTupleBuilder cloneUpdateTb, IIndexCursor cursor)
+                    throws HyracksDataException {
                 try {
                     if (vertex != null && vertex.hasUpdate()) {
                         if (!dynamicStateLength) {
@@ -271,12 +276,16 @@
                             int offset = tupleRef.getFieldStart(1);
                             bbos.setByteArray(data, offset);
                             vertex.write(output);
+
+                            BTreeRangeSearchCursor btreeCursor = (BTreeRangeSearchCursor) cursor;
+                            ICachedPageInternal page = (ICachedPageInternal) btreeCursor.getPage();
+                            //IMPORTANT: mark the page to be dirty
+                            page.markDirty();
                         } else {
                             // write the vertex id
                             DataOutput tbOutput = cloneUpdateTb.getDataOutput();
                             vertex.getVertexId().write(tbOutput);
                             cloneUpdateTb.addFieldEndOffset();
-
                             // write the vertex value
                             vertex.write(tbOutput);
                             cloneUpdateTb.addFieldEndOffset();
diff --git a/pregelix/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/NoOpUpdateFunctionFactory.java b/pregelix/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/NoOpUpdateFunctionFactory.java
index 88577c2..8947c01 100644
--- a/pregelix/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/NoOpUpdateFunctionFactory.java
+++ b/pregelix/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/NoOpUpdateFunctionFactory.java
@@ -20,6 +20,7 @@
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.IIndexCursor;
 import edu.uci.ics.pregelix.dataflow.std.base.IUpdateFunction;
 import edu.uci.ics.pregelix.dataflow.std.base.IUpdateFunctionFactory;
 
@@ -57,7 +58,8 @@
             }
 
             @Override
-            public void update(ITupleReference tupleRef, ArrayTupleBuilder cloneUpdateTb) throws HyracksDataException {
+            public void update(ITupleReference tupleRef, ArrayTupleBuilder cloneUpdateTb, IIndexCursor cursor)
+                    throws HyracksDataException {
 
             }
 
diff --git a/pregelix/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/StartComputeUpdateFunctionFactory.java b/pregelix/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/StartComputeUpdateFunctionFactory.java
index ca8ec01..05b4e87 100644
--- a/pregelix/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/StartComputeUpdateFunctionFactory.java
+++ b/pregelix/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/StartComputeUpdateFunctionFactory.java
@@ -31,6 +31,9 @@
 import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
 import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeRangeSearchCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.IIndexCursor;
+import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPageInternal;
 import edu.uci.ics.pregelix.api.graph.GlobalAggregator;
 import edu.uci.ics.pregelix.api.graph.MsgList;
 import edu.uci.ics.pregelix.api.graph.Vertex;
@@ -113,7 +116,8 @@
             public void open(IHyracksTaskContext ctx, RecordDescriptor rd, IFrameWriter... writers)
                     throws HyracksDataException {
                 this.conf = confFactory.createConfiguration(ctx);
-                this.dynamicStateLength = BspUtils.getDynamicVertexValueSize(conf);
+                //LSM index does not have in-place update
+                this.dynamicStateLength = BspUtils.getDynamicVertexValueSize(conf) || BspUtils.useLSM(conf);;
                 this.aggregator = BspUtils.createGlobalAggregator(conf);
                 this.aggregator.init();
 
@@ -255,7 +259,8 @@
             }
 
             @Override
-            public void update(ITupleReference tupleRef, ArrayTupleBuilder cloneUpdateTb) throws HyracksDataException {
+            public void update(ITupleReference tupleRef, ArrayTupleBuilder cloneUpdateTb, IIndexCursor cursor)
+                    throws HyracksDataException {
                 try {
                     if (vertex != null && vertex.hasUpdate()) {
                         if (!dynamicStateLength) {
@@ -264,6 +269,11 @@
                             int offset = tupleRef.getFieldStart(1);
                             bbos.setByteArray(data, offset);
                             vertex.write(output);
+
+                            BTreeRangeSearchCursor btreeCursor = (BTreeRangeSearchCursor) cursor;
+                            ICachedPageInternal page = (ICachedPageInternal) btreeCursor.getPage();
+                            //IMPORTANT: mark the page to be dirty
+                            page.markDirty();
                         } else {
                             // write the vertex id
                             DataOutput tbOutput = cloneUpdateTb.getDataOutput();