diff --git a/pregelix-api/src/main/java/edu/uci/ics/pregelix/api/graph/Vertex.java b/pregelix-api/src/main/java/edu/uci/ics/pregelix/api/graph/Vertex.java
index 28d424a..a42b411 100644
--- a/pregelix-api/src/main/java/edu/uci/ics/pregelix/api/graph/Vertex.java
+++ b/pregelix-api/src/main/java/edu/uci/ics/pregelix/api/graph/Vertex.java
@@ -259,10 +259,6 @@
     final public void readFields(DataInput in) throws IOException {
         reset();
         if (vertexId == null) {
-            if (getContext().getConfiguration().getClassLoader() != this.getClass().getClassLoader()) {
-                throw new IllegalStateException("mismatched classloader: "
-                        + getContext().getConfiguration().getClassLoader() + " and " + this.getClass().getClassLoader());
-            }
             vertexId = BspUtils.<I> createVertexIndex(getContext().getConfiguration());
         }
         vertexId.readFields(in);
diff --git a/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopJoinFunctionUpdateOperatorNodePushable.java b/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopJoinFunctionUpdateOperatorNodePushable.java
index b646661..c9bda52 100644
--- a/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopJoinFunctionUpdateOperatorNodePushable.java
+++ b/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopJoinFunctionUpdateOperatorNodePushable.java
@@ -104,7 +104,7 @@
     }
 
     protected void setCursor() {
-        cursor = indexAccessor.createSearchCursor();
+        cursor = indexAccessor.createSearchCursor(true);
     }
 
     @Override
diff --git a/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopJoinOperatorNodePushable.java b/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopJoinOperatorNodePushable.java
index 2ddca90..b5b21b6 100644
--- a/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopJoinOperatorNodePushable.java
+++ b/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopJoinOperatorNodePushable.java
@@ -82,7 +82,7 @@
     }
 
     protected void setCursor() {
-        cursor = indexAccessor.createSearchCursor();
+        cursor = indexAccessor.createSearchCursor(false);
     }
 
     @Override
diff --git a/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopRightOuterJoinFunctionUpdateOperatorNodePushable.java b/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopRightOuterJoinFunctionUpdateOperatorNodePushable.java
index 2557a07..d77107e 100644
--- a/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopRightOuterJoinFunctionUpdateOperatorNodePushable.java
+++ b/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopRightOuterJoinFunctionUpdateOperatorNodePushable.java
@@ -115,7 +115,7 @@
     }
 
     protected void setCursor() {
-        cursor = indexAccessor.createSearchCursor();
+        cursor = indexAccessor.createSearchCursor(true);
     }
 
     @Override
diff --git a/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopRightOuterJoinOperatorNodePushable.java b/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopRightOuterJoinOperatorNodePushable.java
index e64e9cc..6539828 100644
--- a/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopRightOuterJoinOperatorNodePushable.java
+++ b/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopRightOuterJoinOperatorNodePushable.java
@@ -89,7 +89,7 @@
     }
 
     protected void setCursor() {
-        cursor = indexAccessor.createSearchCursor();
+        cursor = indexAccessor.createSearchCursor(false);
     }
 
     @Override
diff --git a/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopSetUnionFunctionUpdateOperatorNodePushable.java b/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopSetUnionFunctionUpdateOperatorNodePushable.java
index 1d9fd70..6549782 100644
--- a/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopSetUnionFunctionUpdateOperatorNodePushable.java
+++ b/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopSetUnionFunctionUpdateOperatorNodePushable.java
@@ -106,7 +106,7 @@
     }
 
     protected void setCursor() {
-        cursor = indexAccessor.createSearchCursor();
+        cursor = indexAccessor.createSearchCursor(true);
     }
 
     @Override
diff --git a/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopSetUnionOperatorNodePushable.java b/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopSetUnionOperatorNodePushable.java
index 86a211f..1c9fce6 100644
--- a/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopSetUnionOperatorNodePushable.java
+++ b/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/IndexNestedLoopSetUnionOperatorNodePushable.java
@@ -82,7 +82,7 @@
     }
 
     protected void setCursor() {
-        cursor = indexAccessor.createSearchCursor();
+        cursor = indexAccessor.createSearchCursor(false);
     }
 
     @Override
diff --git a/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/TreeSearchFunctionUpdateOperatorNodePushable.java b/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/TreeSearchFunctionUpdateOperatorNodePushable.java
index 1003431..0561f8b 100644
--- a/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/TreeSearchFunctionUpdateOperatorNodePushable.java
+++ b/pregelix-dataflow-std/src/main/java/edu/uci/ics/pregelix/dataflow/std/TreeSearchFunctionUpdateOperatorNodePushable.java
@@ -172,7 +172,7 @@
     }
 
     protected void setCursor() {
-        cursor = indexAccessor.createSearchCursor();
+        cursor = indexAccessor.createSearchCursor(true);
     }
 
     protected void writeSearchResults() throws Exception {
diff --git a/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/ComputeUpdateFunctionFactory.java b/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/ComputeUpdateFunctionFactory.java
index a39df3c..a002be0 100644
--- a/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/ComputeUpdateFunctionFactory.java
+++ b/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/ComputeUpdateFunctionFactory.java
@@ -31,9 +31,8 @@
 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.hyracks.storage.am.common.api.ITreeIndexCursor;
 import edu.uci.ics.pregelix.api.graph.GlobalAggregator;
 import edu.uci.ics.pregelix.api.graph.MsgList;
 import edu.uci.ics.pregelix.api.graph.Vertex;
@@ -280,11 +279,8 @@
                             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();
+                            ITreeIndexCursor tCursor = (ITreeIndexCursor) cursor;
+                            tCursor.markCurrentTupleAsUpdated();
                         } else {
                             // write the vertex id
                             DataOutput tbOutput = cloneUpdateTb.getDataOutput();
diff --git a/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/StartComputeUpdateFunctionFactory.java b/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/StartComputeUpdateFunctionFactory.java
index 05b4e87..1d26c83 100644
--- a/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/StartComputeUpdateFunctionFactory.java
+++ b/pregelix-runtime/src/main/java/edu/uci/ics/pregelix/runtime/function/StartComputeUpdateFunctionFactory.java
@@ -31,9 +31,8 @@
 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.hyracks.storage.am.common.api.ITreeIndexCursor;
 import edu.uci.ics.pregelix.api.graph.GlobalAggregator;
 import edu.uci.ics.pregelix.api.graph.MsgList;
 import edu.uci.ics.pregelix.api.graph.Vertex;
@@ -269,11 +268,8 @@
                             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();
+                            ITreeIndexCursor tCursor = (ITreeIndexCursor) cursor;
+                            tCursor.markCurrentTupleAsUpdated();
                         } else {
                             // write the vertex id
                             DataOutput tbOutput = cloneUpdateTb.getDataOutput();