diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeSearchOperatorNodePushable.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeSearchOperatorNodePushable.java
index 65b9a33..2f0679c 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeSearchOperatorNodePushable.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeSearchOperatorNodePushable.java
@@ -20,9 +20,9 @@
 import edu.uci.ics.hyracks.storage.am.btree.util.BTreeUtils;
 import edu.uci.ics.hyracks.storage.am.common.api.ISearchPredicate;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.AbstractTreeIndexOperatorDescriptor;
-import edu.uci.ics.hyracks.storage.am.common.dataflow.PermutingFrameTupleReference;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexSearchOperatorNodePushable;
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.tuples.PermutingFrameTupleReference;
 
 public class BTreeSearchOperatorNodePushable extends TreeIndexSearchOperatorNodePushable {
     protected final boolean lowKeyInclusive;
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTree.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTree.java
index a30d17d..b73c0d8 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTree.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTree.java
@@ -915,9 +915,9 @@
     }
 
     @Override
-    public IIndexBulkLoader createBulkLoader(float fillFactor, boolean verifyinput) throws TreeIndexException {
+    public IIndexBulkLoader createBulkLoader(float fillFactor, boolean verifyInput) throws TreeIndexException {
         try {
-            return new BTreeBulkLoader(fillFactor, verifyinput);
+            return new BTreeBulkLoader(fillFactor, verifyInput);
         } catch (HyracksDataException e) {
             throw new TreeIndexException(e);
         }
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexBulkLoadOperatorNodePushable.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexBulkLoadOperatorNodePushable.java
index 9c110e9..3ecc477 100644
--- a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexBulkLoadOperatorNodePushable.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexBulkLoadOperatorNodePushable.java
@@ -26,6 +26,7 @@
 import edu.uci.ics.hyracks.storage.am.common.api.IIndexLifecycleManager;
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
 import edu.uci.ics.hyracks.storage.am.common.api.IndexException;
+import edu.uci.ics.hyracks.storage.am.common.tuples.PermutingFrameTupleReference;
 
 public class TreeIndexBulkLoadOperatorNodePushable extends AbstractUnaryInputSinkOperatorNodePushable {
     private final AbstractTreeIndexOperatorDescriptor opDesc;
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexInsertUpdateDeleteOperatorNodePushable.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexInsertUpdateDeleteOperatorNodePushable.java
index 98fcf4a..3af2b22 100644
--- a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexInsertUpdateDeleteOperatorNodePushable.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexInsertUpdateDeleteOperatorNodePushable.java
@@ -32,6 +32,7 @@
 import edu.uci.ics.hyracks.storage.am.common.api.ITupleFilterFactory;
 import edu.uci.ics.hyracks.storage.am.common.impls.NoOpOperationCallback;
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.tuples.PermutingFrameTupleReference;
 
 public class TreeIndexInsertUpdateDeleteOperatorNodePushable extends AbstractUnaryInputUnaryOutputOperatorNodePushable {
     private final AbstractTreeIndexOperatorDescriptor opDesc;
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/ConcatenatingTupleReference.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/ConcatenatingTupleReference.java
similarity index 98%
rename from hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/ConcatenatingTupleReference.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/ConcatenatingTupleReference.java
index 25218be..87d1055 100644
--- a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/ConcatenatingTupleReference.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/ConcatenatingTupleReference.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.common.dataflow;
+package edu.uci.ics.hyracks.storage.am.common.tuples;
 
 import java.util.Arrays;
 
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/PermutingFrameTupleReference.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/PermutingFrameTupleReference.java
similarity index 96%
rename from hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/PermutingFrameTupleReference.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/PermutingFrameTupleReference.java
index 0b296f0..5f97f04 100644
--- a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/PermutingFrameTupleReference.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/PermutingFrameTupleReference.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.common.dataflow;
+package edu.uci.ics.hyracks.storage.am.common.tuples;
 
 import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.IFrameTupleReference;
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/PermutingTupleReference.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/PermutingTupleReference.java
similarity index 96%
rename from hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/PermutingTupleReference.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/PermutingTupleReference.java
index db50135..0272ff6 100644
--- a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/PermutingTupleReference.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/PermutingTupleReference.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.common.dataflow;
+package edu.uci.ics.hyracks.storage.am.common.tuples;
 
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedListCursor.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedListCursor.java
index 596c265..77fabe1 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedListCursor.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedListCursor.java
@@ -21,33 +21,33 @@
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
 public interface IInvertedListCursor extends Comparable<IInvertedListCursor> {
-    void reset(int startPageId, int endPageId, int startOff, int numElements);
+    public void reset(int startPageId, int endPageId, int startOff, int numElements);
 
-    void pinPagesSync() throws HyracksDataException;
+    public void pinPages() throws HyracksDataException;
 
-    void pinPagesAsync() throws HyracksDataException;
+    public void unpinPages() throws HyracksDataException;
 
-    void unpinPages() throws HyracksDataException;
+    public boolean hasNext() throws HyracksDataException;
 
-    boolean hasNext() throws HyracksDataException;
+    public void next() throws HyracksDataException;
 
-    void next() throws HyracksDataException;
-
-    ITupleReference getTuple();
+    public ITupleReference getTuple();
 
     // getters
-    int getNumElements();
+    public int getNumElements();
 
-    int getStartPageId();
+    public int getStartPageId();
 
-    int getEndPageId();
+    public int getEndPageId();
 
-    int getStartOff();
+    public int getStartOff();
 
-    boolean containsKey(ITupleReference searchTuple, MultiComparator invListCmp) throws HyracksDataException;
+    public boolean containsKey(ITupleReference searchTuple, MultiComparator invListCmp) throws HyracksDataException;
 
     // for debugging
-    String printInvList(ISerializerDeserializer[] serdes) throws HyracksDataException;
+    @SuppressWarnings("rawtypes")
+    public String printInvList(ISerializerDeserializer[] serdes) throws HyracksDataException;
 
-    String printCurrentElement(ISerializerDeserializer[] serdes) throws HyracksDataException;
+    @SuppressWarnings("rawtypes")
+    public String printCurrentElement(ISerializerDeserializer[] serdes) throws HyracksDataException;
 }
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexBulkLoadOperatorNodePushable.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexBulkLoadOperatorNodePushable.java
index c839895..1c423a1 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexBulkLoadOperatorNodePushable.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexBulkLoadOperatorNodePushable.java
@@ -26,7 +26,7 @@
 import edu.uci.ics.hyracks.storage.am.common.api.IIndexBulkLoader;
 import edu.uci.ics.hyracks.storage.am.common.api.IIndexLifecycleManager;
 import edu.uci.ics.hyracks.storage.am.common.api.IndexException;
-import edu.uci.ics.hyracks.storage.am.common.dataflow.PermutingFrameTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.tuples.PermutingFrameTupleReference;
 import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndex;
 
 public class InvertedIndexBulkLoadOperatorNodePushable extends AbstractUnaryInputSinkOperatorNodePushable {
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexDataflowHelper.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexDataflowHelper.java
index 969e099..ed4acd5 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexDataflowHelper.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexDataflowHelper.java
@@ -14,8 +14,11 @@
  */
 package edu.uci.ics.hyracks.storage.am.invertedindex.dataflow;
 
+import java.io.File;
+
 import edu.uci.ics.hyracks.api.context.IHyracksTaskContext;
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.api.io.FileReference;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndex;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexOperatorDescriptor;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexDataflowHelper;
@@ -35,9 +38,10 @@
         IInvertedIndexOperatorDescriptor invIndexOpDesc = (IInvertedIndexOperatorDescriptor) opDesc;
         IInvertedListBuilder invListBuilder = new FixedSizeElementInvertedListBuilder(
                 invIndexOpDesc.getInvListsTypeTraits());
+        FileReference btreeFile = new FileReference(new File(file.getFile().getPath() + "_btree"));
         return new InvertedIndex(opDesc.getStorageManager().getBufferCache(ctx), opDesc.getStorageManager()
                 .getFileMapProvider(ctx), invListBuilder, invIndexOpDesc.getInvListsTypeTraits(),
                 invIndexOpDesc.getInvListsComparatorFactories(), invIndexOpDesc.getTreeIndexTypeTraits(),
-                invIndexOpDesc.getTreeIndexComparatorFactories(), file);
+                invIndexOpDesc.getTreeIndexComparatorFactories(), btreeFile, file);
     }
 }
\ No newline at end of file
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeElementInvertedListCursor.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeElementInvertedListCursor.java
index 431ba55..60a04b0 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeElementInvertedListCursor.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeElementInvertedListCursor.java
@@ -69,12 +69,7 @@
     }
 
     @Override
-    public void pinPagesAsync() {
-        // TODO: implement
-    }
-
-    @Override
-    public void pinPagesSync() throws HyracksDataException {
+    public void pinPages() throws HyracksDataException {
         int pix = 0;
         for (int i = startPageId; i <= endPageId; i++) {
             pages[pix] = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, i), false);
@@ -164,6 +159,7 @@
         elementIndexes[numPages - 1] = numElements - 1;
     }
 
+    @SuppressWarnings("rawtypes")
     @Override
     public String printInvList(ISerializerDeserializer[] serdes) throws HyracksDataException {
         int oldCurrentOff = currentOff;
@@ -176,10 +172,8 @@
 
         StringBuilder strBuilder = new StringBuilder();
 
-        int count = 0;
         while (hasNext()) {
             next();
-            count++;
             for (int i = 0; i < tuple.getFieldCount(); i++) {
                 ByteArrayInputStream inStream = new ByteArrayInputStream(tuple.getFieldData(i), tuple.getFieldStart(i),
                         tuple.getFieldLength(i));
@@ -200,6 +194,7 @@
         return strBuilder.toString();
     }
 
+    @SuppressWarnings("rawtypes")
     public String printCurrentElement(ISerializerDeserializer[] serdes) throws HyracksDataException {
         StringBuilder strBuilder = new StringBuilder();
         for (int i = 0; i < tuple.getFieldCount(); i++) {
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/InvertedIndex.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/InvertedIndex.java
index 707ae42..60caa5d 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/InvertedIndex.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/InvertedIndex.java
@@ -15,7 +15,6 @@
 
 package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
 
-import java.io.File;
 import java.nio.ByteBuffer;
 
 import edu.uci.ics.hyracks.api.context.IHyracksCommonContext;
@@ -28,10 +27,8 @@
 import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleReference;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
-import edu.uci.ics.hyracks.storage.am.btree.exceptions.BTreeException;
 import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeLeafFrameType;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
-import edu.uci.ics.hyracks.storage.am.btree.impls.RangePredicate;
 import edu.uci.ics.hyracks.storage.am.btree.util.BTreeUtils;
 import edu.uci.ics.hyracks.storage.am.common.api.IIndexAccessor;
 import edu.uci.ics.hyracks.storage.am.common.api.IIndexBulkLoader;
@@ -40,8 +37,6 @@
 import edu.uci.ics.hyracks.storage.am.common.api.IModificationOperationCallback;
 import edu.uci.ics.hyracks.storage.am.common.api.ISearchOperationCallback;
 import edu.uci.ics.hyracks.storage.am.common.api.ISearchPredicate;
-import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexAccessor;
-import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
 import edu.uci.ics.hyracks.storage.am.common.api.IndexException;
 import edu.uci.ics.hyracks.storage.am.common.api.IndexType;
 import edu.uci.ics.hyracks.storage.am.common.api.TreeIndexException;
@@ -66,40 +61,43 @@
 public class InvertedIndex implements IInvertedIndex {
     private final IHyracksCommonContext ctx = new DefaultHyracksCommonContext();
 
+    // Schema of BTree tuples.
+    public final int TOKEN_FIELD = 0;
+    public final int INVLIST_START_PAGE_ID_FIELD = 1;
+    public final int INVLIST_END_PAGE_ID_FIELD = 2;
+    public final int INVLIST_START_OFF_FIELD = 3;
+    public final int INVLIST_NUM_ELEMENTS_FIELD = 4;
+    
     private BTree btree;
     private int rootPageId = 0;
     private IBufferCache bufferCache;
     private IFileMapProvider fileMapProvider;
     private int fileId = -1;
-    private FileReference file;
     private final ITypeTraits[] invListTypeTraits;
     private final IBinaryComparatorFactory[] invListCmpFactories;
     private final IInvertedListBuilder invListBuilder;
     private final int numTokenFields;
     private final int numInvListKeys;
-
+    private final FileReference invListsFile;
+    
     private boolean isOpen = false;
 
     public InvertedIndex(IBufferCache bufferCache, IFileMapProvider fileMapProvider,
             IInvertedListBuilder invListBuilder, ITypeTraits[] invListTypeTraits,
             IBinaryComparatorFactory[] invListCmpFactories, ITypeTraits[] tokenTypeTraits,
-            IBinaryComparatorFactory[] tokenCmpFactories, FileReference file) throws HyracksDataException {
+            IBinaryComparatorFactory[] tokenCmpFactories, FileReference btreeFile, FileReference invListsFile)
+            throws IndexException {
         this.bufferCache = bufferCache;
         this.fileMapProvider = fileMapProvider;
         this.invListBuilder = invListBuilder;
-
         this.invListTypeTraits = invListTypeTraits;
         this.invListCmpFactories = invListCmpFactories;
-        try {
-            this.btree = BTreeUtils.createBTree(bufferCache, fileMapProvider,
-                    InvertedIndexUtils.getBTreeTypeTraits(tokenTypeTraits), tokenCmpFactories,
-                    BTreeLeafFrameType.REGULAR_NSM, new FileReference(new File(file.getFile().getPath() + "_btree")));
-        } catch (BTreeException e) {
-            throw new HyracksDataException(e);
-        }
+        this.btree = BTreeUtils.createBTree(bufferCache, fileMapProvider,
+                InvertedIndexUtils.getBTreeTypeTraits(tokenTypeTraits), tokenCmpFactories,
+                BTreeLeafFrameType.REGULAR_NSM, btreeFile);
         this.numTokenFields = btree.getComparatorFactories().length;
         this.numInvListKeys = invListCmpFactories.length;
-        this.file = file;
+        this.invListsFile = invListsFile;
     }
 
     @Override
@@ -111,11 +109,11 @@
 
         boolean fileIsMapped = false;
         synchronized (fileMapProvider) {
-            fileIsMapped = fileMapProvider.isMapped(file);
+            fileIsMapped = fileMapProvider.isMapped(invListsFile);
             if (!fileIsMapped) {
-                bufferCache.createFile(file);
+                bufferCache.createFile(invListsFile);
             }
-            fileId = fileMapProvider.lookupFileId(file);
+            fileId = fileMapProvider.lookupFileId(invListsFile);
             try {
                 // Also creates the file if it doesn't exist yet.
                 bufferCache.openFile(fileId);
@@ -139,11 +137,11 @@
         btree.activate();
         boolean fileIsMapped = false;
         synchronized (fileMapProvider) {
-            fileIsMapped = fileMapProvider.isMapped(file);
+            fileIsMapped = fileMapProvider.isMapped(invListsFile);
             if (!fileIsMapped) {
-                bufferCache.createFile(file);
+                bufferCache.createFile(invListsFile);
             }
-            fileId = fileMapProvider.lookupFileId(file);
+            fileId = fileMapProvider.lookupFileId(invListsFile);
             try {
                 // Also creates the file if it doesn't exist yet.
                 bufferCache.openFile(fileId);
@@ -178,7 +176,7 @@
         }
 
         btree.destroy();
-        file.getFile().delete();
+        invListsFile.getFile().delete();
         if (fileId == -1) {
             return;
         }
@@ -195,15 +193,15 @@
         btree.clear();
         bufferCache.closeFile(fileId);
         bufferCache.deleteFile(fileId, false);
-        file.getFile().delete();
+        invListsFile.getFile().delete();
 
         boolean fileIsMapped = false;
         synchronized (fileMapProvider) {
-            fileIsMapped = fileMapProvider.isMapped(file);
+            fileIsMapped = fileMapProvider.isMapped(invListsFile);
             if (!fileIsMapped) {
-                bufferCache.createFile(file);
+                bufferCache.createFile(invListsFile);
             }
-            fileId = fileMapProvider.lookupFileId(file);
+            fileId = fileMapProvider.lookupFileId(invListsFile);
             try {
                 // Also creates the file if it doesn't exist yet.
                 bufferCache.openFile(fileId);
@@ -217,35 +215,37 @@
         }
     }
 
-    public boolean openCursor(ITreeIndexCursor btreeCursor, RangePredicate btreePred, ITreeIndexAccessor btreeAccessor,
-            IInvertedListCursor invListCursor) throws HyracksDataException, IndexException {
-        btreeAccessor.search(btreeCursor, btreePred);
-        boolean ret = false;
+    @Override
+    public void openInvertedListCursor(IInvertedListCursor listCursor, ITupleReference searchKey, IIndexOpContext ictx)
+            throws HyracksDataException, IndexException {
+        InvertedIndexOpContext ctx = (InvertedIndexOpContext) ictx;
+        ctx.btreePred.setLowKeyComparator(ctx.searchCmp);
+        ctx.btreePred.setHighKeyComparator(ctx.searchCmp);
+        ctx.btreePred.setLowKey(searchKey, true);
+        ctx.btreePred.setHighKey(searchKey, true);
+        ctx.btreeAccessor.search(ctx.btreeCursor, ctx.btreePred);
         try {
-            if (btreeCursor.hasNext()) {
-                btreeCursor.next();
-                ITupleReference frameTuple = btreeCursor.getTuple();
-                // Hardcoded mapping of btree fields
-                int startPageId = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(1),
-                        frameTuple.getFieldStart(1));
-                int endPageId = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(2),
-                        frameTuple.getFieldStart(2));
-                int startOff = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(3),
-                        frameTuple.getFieldStart(3));
-                int numElements = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(4),
-                        frameTuple.getFieldStart(4));
-                invListCursor.reset(startPageId, endPageId, startOff, numElements);
-                ret = true;
+            if (ctx.btreeCursor.hasNext()) {
+                ctx.btreeCursor.next();
+                ITupleReference frameTuple = ctx.btreeCursor.getTuple();
+                int startPageId = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(INVLIST_START_PAGE_ID_FIELD),
+                        frameTuple.getFieldStart(INVLIST_START_PAGE_ID_FIELD));
+                int endPageId = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(INVLIST_END_PAGE_ID_FIELD),
+                        frameTuple.getFieldStart(INVLIST_END_PAGE_ID_FIELD));
+                int startOff = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(INVLIST_START_OFF_FIELD),
+                        frameTuple.getFieldStart(INVLIST_START_OFF_FIELD));
+                int numElements = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(INVLIST_NUM_ELEMENTS_FIELD),
+                        frameTuple.getFieldStart(INVLIST_NUM_ELEMENTS_FIELD));
+                listCursor.reset(startPageId, endPageId, startOff, numElements);
             } else {
-                invListCursor.reset(0, 0, 0, 0);
+                listCursor.reset(0, 0, 0, 0);
             }
         } finally {
-            btreeCursor.close();
-            btreeCursor.reset();
+            ctx.btreeCursor.close();
+            ctx.btreeCursor.reset();
         }
-        return ret;
     }
-
+    
     public final class InvertedIndexBulkLoader implements IIndexBulkLoader {
         private final ArrayTupleBuilder btreeTupleBuilder;
         private final ArrayTupleReference btreeTupleReference;
@@ -289,6 +289,7 @@
             btreeTupleBuilder.reset();
             btreeTupleBuilder.addField(lastTuple.getFieldData(0), lastTuple.getFieldStart(0),
                     lastTuple.getFieldLength(0));
+            // TODO: Boxing integers here. Fix it.
             btreeTupleBuilder.addField(IntegerSerializerDeserializer.INSTANCE, currentInvListStartPageId);
             btreeTupleBuilder.addField(IntegerSerializerDeserializer.INSTANCE, currentPageId);
             btreeTupleBuilder.addField(IntegerSerializerDeserializer.INSTANCE, currentInvListStartOffset);
@@ -488,36 +489,4 @@
     public IInvertedListCursor createInvertedListCursor() {
         return new FixedSizeElementInvertedListCursor(bufferCache, fileId, invListTypeTraits);
     }
-
-    @Override
-    public void openInvertedListCursor(IInvertedListCursor listCursor, ITupleReference searchKey, IIndexOpContext ictx)
-            throws HyracksDataException, IndexException {
-        InvertedIndexOpContext ctx = (InvertedIndexOpContext) ictx;
-        ctx.btreePred.setLowKeyComparator(ctx.searchCmp);
-        ctx.btreePred.setHighKeyComparator(ctx.searchCmp);
-        ctx.btreePred.setLowKey(searchKey, true);
-        ctx.btreePred.setHighKey(searchKey, true);
-        ctx.btreeAccessor.search(ctx.btreeCursor, ctx.btreePred);
-        try {
-            if (ctx.btreeCursor.hasNext()) {
-                ctx.btreeCursor.next();
-                ITupleReference frameTuple = ctx.btreeCursor.getTuple();
-                // Hardcoded mapping of btree fields.
-                int startPageId = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(1),
-                        frameTuple.getFieldStart(1));
-                int endPageId = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(2),
-                        frameTuple.getFieldStart(2));
-                int startOff = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(3),
-                        frameTuple.getFieldStart(3));
-                int numElements = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(4),
-                        frameTuple.getFieldStart(4));
-                listCursor.reset(startPageId, endPageId, startOff, numElements);
-            } else {
-                listCursor.reset(0, 0, 0, 0);
-            }
-        } finally {
-            ctx.btreeCursor.close();
-            ctx.btreeCursor.reset();
-        }
-    }
 }
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcher.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcher.java
index 2ddfa31..a028af4 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcher.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcher.java
@@ -188,7 +188,7 @@
             newResultBuffers = swap;
             currentNumResults = 0;
 
-            invListCursors.get(i).pinPagesSync();
+            invListCursors.get(i).pinPages();
             maxPrevBufIdx = mergePrefixList(invListCursors.get(i), prevResultBuffers, maxPrevBufIdx, newResultBuffers);
             invListCursors.get(i).unpinPages();
         }
@@ -202,7 +202,7 @@
             prevResultBuffers = newResultBuffers;
             newResultBuffers = swap;
 
-            invListCursors.get(i).pinPagesSync();
+            invListCursors.get(i).pinPages();
             int numInvListElements = invListCursors.get(i).getNumElements();
             // should we binary search the next list or should we sort-merge it?
             if (currentNumResults * Math.log(numInvListElements) < currentNumResults + numInvListElements) {
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcherSuffixProbeOnly.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcherSuffixProbeOnly.java
index e25be73..436a02d 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcherSuffixProbeOnly.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcherSuffixProbeOnly.java
@@ -40,7 +40,7 @@
             newResultBuffers = swap;
             currentNumResults = 0;
 
-            invListCursors.get(i).pinPagesSync();
+            invListCursors.get(i).pinPages();
             maxPrevBufIdx = mergeSuffixListProbe(invListCursors.get(i), prevResultBuffers, maxPrevBufIdx,
                     newResultBuffers, i, numQueryTokens);
             invListCursors.get(i).unpinPages();
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcherSuffixScanOnly.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcherSuffixScanOnly.java
index 131dc48..a41c940 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcherSuffixScanOnly.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcherSuffixScanOnly.java
@@ -41,7 +41,7 @@
             newResultBuffers = swap;
             currentNumResults = 0;
 
-            invListCursors.get(i).pinPagesSync();
+            invListCursors.get(i).pinPages();
             maxPrevBufIdx = mergeSuffixListScan(invListCursors.get(i), prevResultBuffers, maxPrevBufIdx,
                     newResultBuffers, i, numQueryTokens);
             invListCursors.get(i).unpinPages();
diff --git a/hyracks-storage-am-lsm-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/rtree/impls/LSMRTreeInMemoryBufferCache.java b/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/freepage/DualIndexInMemoryBufferCache.java
similarity index 83%
rename from hyracks-storage-am-lsm-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/rtree/impls/LSMRTreeInMemoryBufferCache.java
rename to hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/freepage/DualIndexInMemoryBufferCache.java
index 15de7e6..c24c473 100644
--- a/hyracks-storage-am-lsm-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/rtree/impls/LSMRTreeInMemoryBufferCache.java
+++ b/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/freepage/DualIndexInMemoryBufferCache.java
@@ -13,19 +13,22 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.lsm.rtree.impls;
+package edu.uci.ics.hyracks.storage.am.lsm.common.freepage;
 
 import java.nio.ByteBuffer;
 
-import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.InMemoryBufferCache;
 import edu.uci.ics.hyracks.storage.common.buffercache.ICacheMemoryAllocator;
 import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
 import edu.uci.ics.hyracks.storage.common.file.BufferedFileHandle;
 import edu.uci.ics.hyracks.storage.common.file.TransientFileMapManager;
 
-public class LSMRTreeInMemoryBufferCache extends InMemoryBufferCache {
+/**
+ * In-memory buffer cache that supports two tree indexes.
+ * We assume that the tree indexes have 2 fixed pages, one at index 0 (metadata page), and one at index 1 (root page).
+ */
+public class DualIndexInMemoryBufferCache extends InMemoryBufferCache {
 
-    public LSMRTreeInMemoryBufferCache(ICacheMemoryAllocator allocator, int pageSize, int numPages) {
+    public DualIndexInMemoryBufferCache(ICacheMemoryAllocator allocator, int pageSize, int numPages) {
         super(allocator, pageSize, numPages, new TransientFileMapManager());
     }
 
@@ -33,10 +36,8 @@
     public ICachedPage pin(long dpid, boolean newPage) {
         int pageId = BufferedFileHandle.getPageId(dpid);
         int fileId = BufferedFileHandle.getFileId(dpid);
-
         if (pageId < pages.length) {
             // Common case: Return regular page.
-
             if (pageId == 0 || pageId == 1) {
                 return pages[pageId + 2 * fileId];
             } else {
diff --git a/hyracks-storage-am-lsm-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/rtree/impls/LSMRTreeInMemoryFreePageManager.java b/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/freepage/DualIndexInMemoryFreePageManager.java
similarity index 77%
rename from hyracks-storage-am-lsm-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/rtree/impls/LSMRTreeInMemoryFreePageManager.java
rename to hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/freepage/DualIndexInMemoryFreePageManager.java
index dd1f0ec..7a2be7f 100644
--- a/hyracks-storage-am-lsm-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/rtree/impls/LSMRTreeInMemoryFreePageManager.java
+++ b/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/freepage/DualIndexInMemoryFreePageManager.java
@@ -13,16 +13,19 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.lsm.rtree.impls;
+package edu.uci.ics.hyracks.storage.am.lsm.common.freepage;
 
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrameFactory;
-import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.InMemoryFreePageManager;
 
-public class LSMRTreeInMemoryFreePageManager extends InMemoryFreePageManager {
+/**
+ * In-memory free page manager that supports two tree indexes.
+ * We assume that the tree indexes have 2 fixed pages, one at index 0 (metadata page), and one at index 1 (root page).
+ */
+public class DualIndexInMemoryFreePageManager extends InMemoryFreePageManager {
 
-    public LSMRTreeInMemoryFreePageManager(int capacity, ITreeIndexMetaDataFrameFactory metaDataFrameFactory) {
+    public DualIndexInMemoryFreePageManager(int capacity, ITreeIndexMetaDataFrameFactory metaDataFrameFactory) {
         super(capacity, metaDataFrameFactory);
         // We start the currentPageId from 3, because the RTree uses
         // the first page as metadata page, and the second page as root page.
@@ -39,7 +42,7 @@
     public int getCapacity() {
         return capacity - 4;
     }
-    
+
     public void reset() {
         currentPageId.set(3);
     }
diff --git a/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/IndexFactory.java b/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/IndexFactory.java
index ac81515..e2254ec 100644
--- a/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/IndexFactory.java
+++ b/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/IndexFactory.java
@@ -17,6 +17,7 @@
 
 import edu.uci.ics.hyracks.api.io.FileReference;
 import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManagerFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.IndexException;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndex;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
 import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
@@ -34,7 +35,7 @@
         this.freePageManagerFactory = freePageManagerFactory;
     }
 
-    public abstract T createIndexInstance(FileReference file);
+    public abstract T createIndexInstance(FileReference file) throws IndexException;
 
     public IBufferCache getBufferCache() {
         return bufferCache;
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InvertedIndexFactory.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InvertedIndexFactory.java
deleted file mode 100644
index 2f4bac6..0000000
--- a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InvertedIndexFactory.java
+++ /dev/null
@@ -1,81 +0,0 @@
-/*
- * Copyright 2009-2012 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.hyracks.storage.am.lsm.invertedindex.impls;
-
-import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
-import edu.uci.ics.hyracks.api.dataflow.value.ITypeTraits;
-import edu.uci.ics.hyracks.api.io.FileReference;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
-import edu.uci.ics.hyracks.storage.am.btree.impls.RangePredicate;
-import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManagerFactory;
-import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
-import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
-import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndex;
-import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListBuilder;
-import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndex;
-import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IBinaryTokenizer;
-import edu.uci.ics.hyracks.storage.am.lsm.common.api.ILSMFileManager;
-import edu.uci.ics.hyracks.storage.am.lsm.common.impls.IndexFactory;
-import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
-import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
-
-public class InvertedIndexFactory extends IndexFactory<IIndex> {
-
-    protected ITypeTraits[] invListTypeTraits;
-    protected IBinaryComparatorFactory[] invListCmpFactories;
-    protected IInvertedListBuilder invListBuilder;
-    protected IBinaryTokenizer tokenizer;
-    protected int numTokenFields;
-    protected int numInvListKeys;
-    
-    protected RangePredicate btreePred;
-    protected ITreeIndexFrame leafFrame;
-    protected ITreeIndexCursor btreeCursor;
-    protected MultiComparator searchCmp;
-    
-    protected ILSMFileManager fileManager;
-    
-    public InvertedIndexFactory(IBufferCache bufferCache, IFileMapProvider fileMapProvider,
-            IFreePageManagerFactory freePageManagerFactory, ITypeTraits[] invListTypeTraits,
-            IBinaryComparatorFactory[] invListCmpFactories, IInvertedListBuilder invListBuilder,
-            IBinaryTokenizer tokenizer, ILSMFileManager fileManager) {
-        super(bufferCache, fileMapProvider, freePageManagerFactory);
-        this.invListTypeTraits = invListTypeTraits;
-        this.invListCmpFactories = invListCmpFactories;
-        this.invListBuilder = invListBuilder;
-        this.tokenizer = tokenizer;
-        //this.numTokenFields = btree.getComparatorFactories().length;
-        this.numInvListKeys = invListCmpFactories.length;
-
-        // setup for cursor creation
-//        
-//        btreePred = new RangePredicate(null, null, true, true, null, null);
-//        leafFrame = btree.getLeafFrameFactory().createFrame();
-//        btreeCursor = new BTreeRangeSearchCursor((IBTreeLeafFrame) leafFrame, false);
-//        searchCmp = MultiComparator.create(btree.getComparatorFactories());
-//        btreePred.setLowKeyComparator(searchCmp);
-//        btreePred.setHighKeyComparator(searchCmp);
-        
-        // fileManager for creating a file of a diskInvertedIndex
-        this.fileManager = fileManager;
-    }
-
-    @Override
-    public IIndex createIndexInstance(FileReference file) {
-        return new InvertedIndex(bufferCache, btree, invListTypeTraits, invListCmpFactories, invListBuilder,
-                tokenizer); ;
-    }
-}
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InMemoryBtreeInvertedIndex.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InMemoryInvertedIndex.java
similarity index 91%
rename from hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InMemoryBtreeInvertedIndex.java
rename to hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InMemoryInvertedIndex.java
index 8b648ae..1fb1683 100644
--- a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InMemoryBtreeInvertedIndex.java
+++ b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InMemoryInvertedIndex.java
@@ -12,7 +12,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls;
+package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory;
 
 import java.io.File;
 import java.io.IOException;
@@ -43,7 +43,7 @@
 import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.InMemoryBufferCache;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
 
-public class InMemoryBtreeInvertedIndex implements IInvertedIndex {
+public class InMemoryInvertedIndex implements IInvertedIndex {
 
     private final BTree btree;
     private final FileReference memBTreeFile = new FileReference(new File("memBTree"));
@@ -56,7 +56,7 @@
     private final ITypeTraits[] btreeTypeTraits;
     private final IBinaryComparatorFactory[] btreeCmpFactories;
 
-    public InMemoryBtreeInvertedIndex(IBufferCache memBufferCache, IFreePageManager memFreePageManager,
+    public InMemoryInvertedIndex(IBufferCache memBufferCache, IFreePageManager memFreePageManager,
             ITypeTraits[] invListTypeTraits, IBinaryComparatorFactory[] invListCmpFactories,
             ITypeTraits[] tokenTypeTraits, IBinaryComparatorFactory[] tokenCmpFactories, IBinaryTokenizer tokenizer)
             throws BTreeException {
@@ -114,7 +114,7 @@
 
     public boolean insert(ITupleReference tuple, BTreeAccessor btreeAccessor, IIndexOpContext ictx)
             throws HyracksDataException, IndexException {
-        InMemoryBtreeInvertedIndexOpContext ctx = (InMemoryBtreeInvertedIndexOpContext) ictx;
+        InMemoryInvertedIndexOpContext ctx = (InMemoryInvertedIndexOpContext) ictx;
         // TODO: We can possibly avoid copying the data into a new tuple here.
         tokenizer.reset(tuple.getFieldData(0), tuple.getFieldStart(0), tuple.getFieldLength(0));
         while (tokenizer.hasNext()) {
@@ -155,24 +155,22 @@
 
     @Override
     public IInvertedListCursor createInvertedListCursor() {
-        return new InMemoryBtreeInvertedListCursor(invListTypeTraits.length, tokenTypeTraits.length);
+        return new InMemoryInvertedListCursor(invListTypeTraits.length, tokenTypeTraits.length);
     }
 
     @Override
     public void openInvertedListCursor(IInvertedListCursor listCursor, ITupleReference tupleReference, IIndexOpContext ictx)
             throws HyracksDataException, IndexException {
-        InMemoryBtreeInvertedIndexOpContext ctx = (InMemoryBtreeInvertedIndexOpContext) ictx;
-        InMemoryBtreeInvertedListCursor inMemListCursor = (InMemoryBtreeInvertedListCursor) listCursor;
+        InMemoryInvertedIndexOpContext ctx = (InMemoryInvertedIndexOpContext) ictx;
+        InMemoryInvertedListCursor inMemListCursor = (InMemoryInvertedListCursor) listCursor;
         inMemListCursor.prepare(ctx.btreeAccessor, ctx.btreePred, ctx.tokenFieldsCmp, ctx.btreeCmp);
-        
-        
         inMemListCursor.reset(tupleReference);
     }
 
     @Override
     public IIndexAccessor createAccessor(IModificationOperationCallback modificationCallback,
             ISearchOperationCallback searchCallback) {
-        return new InMemoryBtreeInvertedIndexAccessor(this, new InMemoryBtreeInvertedIndexOpContext(
+        return new InMemoryInvertedIndexAccessor(this, new InMemoryInvertedIndexOpContext(
                 btree, tokenCmpFactories), tokenizer);
     }
 
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InMemoryBtreeInvertedIndexAccessor.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InMemoryInvertedIndexAccessor.java
similarity index 92%
rename from hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InMemoryBtreeInvertedIndexAccessor.java
rename to hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InMemoryInvertedIndexAccessor.java
index cc74b9e..0cf4f3b 100644
--- a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InMemoryBtreeInvertedIndexAccessor.java
+++ b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InMemoryInvertedIndexAccessor.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls;
+package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory;
 
 import edu.uci.ics.hyracks.api.context.IHyracksCommonContext;
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
@@ -33,15 +33,15 @@
 import edu.uci.ics.hyracks.storage.am.invertedindex.impls.TOccurrenceSearcher;
 import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IBinaryTokenizer;
 
-public class InMemoryBtreeInvertedIndexAccessor implements IIndexAccessor {
+public class InMemoryInvertedIndexAccessor implements IIndexAccessor {
     // TODO: This ctx needs to go away.
     protected final IHyracksCommonContext hyracksCtx = new DefaultHyracksCommonContext();
     protected final IInvertedIndexSearcher searcher;
     protected IIndexOpContext opCtx;
-    protected InMemoryBtreeInvertedIndex memoryBtreeInvertedIndex;
+    protected InMemoryInvertedIndex memoryBtreeInvertedIndex;
     protected BTreeAccessor btreeAccessor;
 
-    public InMemoryBtreeInvertedIndexAccessor(InMemoryBtreeInvertedIndex memoryBtreeInvertedIndex,
+    public InMemoryInvertedIndexAccessor(InMemoryInvertedIndex memoryBtreeInvertedIndex,
             IIndexOpContext opCtx, IBinaryTokenizer tokenizer) {
         this.opCtx = opCtx;
         this.memoryBtreeInvertedIndex = memoryBtreeInvertedIndex;
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InMemoryBtreeInvertedIndexOpContext.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InMemoryInvertedIndexOpContext.java
similarity index 91%
rename from hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InMemoryBtreeInvertedIndexOpContext.java
rename to hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InMemoryInvertedIndexOpContext.java
index eb75b88..0dd9774 100644
--- a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InMemoryBtreeInvertedIndexOpContext.java
+++ b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InMemoryInvertedIndexOpContext.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls;
+package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory;
 
 import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
 import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
@@ -26,7 +26,7 @@
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
-public class InMemoryBtreeInvertedIndexOpContext implements IIndexOpContext {
+public class InMemoryInvertedIndexOpContext implements IIndexOpContext {
     public IndexOp op;
     public final BTree btree;
 
@@ -41,7 +41,7 @@
     public ArrayTupleBuilder btreeTupleBuilder;
     public ArrayTupleReference btreeTupleReference;
 
-    public InMemoryBtreeInvertedIndexOpContext(BTree btree, IBinaryComparatorFactory[] tokenCmpFactories) {
+    public InMemoryInvertedIndexOpContext(BTree btree, IBinaryComparatorFactory[] tokenCmpFactories) {
         this.btree = btree;
         this.tokenCmpFactories = tokenCmpFactories;
     }
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InMemoryBtreeInvertedListCursor.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InMemoryInvertedListCursor.java
similarity index 92%
rename from hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InMemoryBtreeInvertedListCursor.java
rename to hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InMemoryInvertedListCursor.java
index ffb0169..b0f07c6 100644
--- a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InMemoryBtreeInvertedListCursor.java
+++ b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InMemoryInvertedListCursor.java
@@ -12,7 +12,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls;
+package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory;
 
 import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
@@ -26,12 +26,12 @@
 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.am.common.api.TreeIndexException;
-import edu.uci.ics.hyracks.storage.am.common.dataflow.ConcatenatingTupleReference;
-import edu.uci.ics.hyracks.storage.am.common.dataflow.PermutingTupleReference;
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.tuples.ConcatenatingTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.tuples.PermutingTupleReference;
 import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListCursor;
 
-public class InMemoryBtreeInvertedListCursor implements IInvertedListCursor {
+public class InMemoryInvertedListCursor implements IInvertedListCursor {
     private RangePredicate btreePred;
     private BTreeAccessor btreeAccessor;
     private IIndexCursor btreeCursor;
@@ -46,7 +46,7 @@
     
     private int numElements = -1;
     
-    public InMemoryBtreeInvertedListCursor(int invListFieldCount, int tokenFieldCount) {
+    public InMemoryInvertedListCursor(int invListFieldCount, int tokenFieldCount) {
         int[] fieldPermutation = new int[invListFieldCount];
         for (int i = 0; i < invListFieldCount; i++) {
             fieldPermutation[i] = tokenFieldCount + i;
@@ -91,12 +91,7 @@
     }
 
     @Override
-    public void pinPagesSync() throws HyracksDataException {
-        // Do nothing
-    }
-
-    @Override
-    public void pinPagesAsync() throws HyracksDataException {
+    public void pinPages() throws HyracksDataException {
         // Do nothing
     }
 
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InvertedIndexComponentFinalizer.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InvertedIndexComponentFinalizer.java
similarity index 84%
rename from hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InvertedIndexComponentFinalizer.java
rename to hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InvertedIndexComponentFinalizer.java
index eb02571..6c89e04 100644
--- a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/InvertedIndexComponentFinalizer.java
+++ b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InvertedIndexComponentFinalizer.java
@@ -1,6 +1,19 @@
-package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls;
+/*
+ * Copyright 2009-2010 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.
+ */
 
-import java.io.File;
+package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory;
 
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.api.io.FileReference;
@@ -22,7 +35,7 @@
     }
     
     @Override
-    public boolean isValid(File file, Object lsmComponent) throws HyracksDataException {
+    public boolean isValid(Object lsmComponent) throws HyracksDataException {
         InvertedIndex index = (InvertedIndex) lsmComponent;
         ITreeIndex treeIndex = index.getBTree();
         IBufferCache bufferCache = treeIndex.getBufferCache();
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InvertedIndexFactory.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InvertedIndexFactory.java
new file mode 100644
index 0000000..8aa2a19
--- /dev/null
+++ b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/InvertedIndexFactory.java
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2009-2012 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.hyracks.storage.am.lsm.invertedindex.inmemory;
+
+import java.io.File;
+
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTraits;
+import edu.uci.ics.hyracks.api.io.FileReference;
+import edu.uci.ics.hyracks.storage.am.common.api.IndexException;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndex;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListBuilder;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndex;
+import edu.uci.ics.hyracks.storage.am.lsm.common.impls.IndexFactory;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
+
+public class InvertedIndexFactory extends IndexFactory<IIndex> {
+
+    protected final IInvertedListBuilder invListBuilder;
+    protected final ITypeTraits[] invListTypeTraits;
+    protected final IBinaryComparatorFactory[] invListCmpFactories;
+    protected final ITypeTraits[] tokenTypeTraits;
+    protected final IBinaryComparatorFactory[] tokenCmpFactories;
+
+    public InvertedIndexFactory(IBufferCache bufferCache, IFileMapProvider fileMapProvider,
+            IInvertedListBuilder invListBuilder, ITypeTraits[] invListTypeTraits,
+            IBinaryComparatorFactory[] invListCmpFactories, ITypeTraits[] tokenTypeTraits,
+            IBinaryComparatorFactory[] tokenCmpFactories) {
+        super(bufferCache, fileMapProvider, null);
+        this.invListBuilder = invListBuilder;
+        this.invListTypeTraits = invListTypeTraits;
+        this.invListCmpFactories = invListCmpFactories;
+        this.tokenTypeTraits = tokenTypeTraits;
+        this.tokenCmpFactories = tokenCmpFactories;
+    }
+
+    @Override
+    public IIndex createIndexInstance(FileReference file) throws IndexException {
+        FileReference btreeFile = new FileReference(new File(file.getFile().getPath() + "_btree"));
+        return new InvertedIndex(bufferCache, fileMapProvider, invListBuilder, invListTypeTraits, invListCmpFactories,
+                tokenTypeTraits, tokenCmpFactories, btreeFile, file);
+    }
+}
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndex.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndex.java
similarity index 97%
rename from hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndex.java
rename to hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndex.java
index 63f73a4..4bf4853 100644
--- a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndex.java
+++ b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndex.java
@@ -12,7 +12,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls;
+package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory;
 
 import java.util.ArrayList;
 import java.util.LinkedList;
@@ -53,7 +53,7 @@
 import edu.uci.ics.hyracks.storage.am.lsm.common.api.ILSMOperationTracker;
 import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.InMemoryFreePageManager;
 import edu.uci.ics.hyracks.storage.am.lsm.common.impls.LSMHarness;
-import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls.LSMInvertedIndexFileManager.LSMInvertedFileNameComponent;
+import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory.LSMInvertedIndexFileManager.LSMInvertedFileNameComponent;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
 import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
 
@@ -111,7 +111,7 @@
             IBinaryComparatorFactory[] tokenCmpFactories, ILSMFlushController flushController,
             ILSMMergePolicy mergePolicy, ILSMOperationTracker opTracker, ILSMIOOperationScheduler ioScheduler) {
         // TODO: Finish this one properly.
-        InMemoryBtreeInvertedIndex memInvIndex = null;
+        InMemoryInvertedIndex memInvIndex = null;
         BTree deleteKeysBTree = null;
         memComponent = new LSMInvertedIndexComponent(memInvIndex, deleteKeysBTree);
         this.memBufferCache = memBufferCache;
@@ -355,7 +355,7 @@
         // ---------------------------------------------------
 
         // #. Create a scanCursor of memoryInvertedIndex to iterate all keys in it.
-        BTree inMemBtree = ((InMemoryBtreeInvertedIndex) memoryInvertedIndex).getBTree();
+        BTree inMemBtree = ((InMemoryInvertedIndex) memoryInvertedIndex).getBTree();
         IIndexAccessor btreeAccessor = inMemBtree.createAccessor();
         MultiComparator btreeMultiComparator = MultiComparator.create(inMemBtree.getComparatorFactories());
         RangePredicate scanPred = new RangePredicate(null, null, true, true, btreeMultiComparator, btreeMultiComparator);
@@ -438,7 +438,7 @@
     public InMemoryFreePageManager getInMemoryFreePageManager() {
         // TODO This code should be changed more generally if IInMemoryInvertedIndex interface is defined and
         //      InMemoryBtreeInvertedIndex implements IInMemoryInvertedIndex
-        InMemoryBtreeInvertedIndex memoryBTreeInvertedIndex = (InMemoryBtreeInvertedIndex) memoryInvertedIndex;
+        InMemoryInvertedIndex memoryBTreeInvertedIndex = (InMemoryInvertedIndex) memoryInvertedIndex;
         return (InMemoryFreePageManager) memoryBTreeInvertedIndex.getBTree().getFreePageManager();
     }
 
@@ -446,7 +446,7 @@
     public void resetInMemoryComponent() throws HyracksDataException {
         // TODO This code should be changed more generally if IInMemoryInvertedIndex interface is defined and
         //      InMemoryBtreeInvertedIndex implements IInMemoryInvertedIndex
-        InMemoryBtreeInvertedIndex memoryBTreeInvertedIndex = (InMemoryBtreeInvertedIndex) memoryInvertedIndex;
+        InMemoryInvertedIndex memoryBTreeInvertedIndex = (InMemoryInvertedIndex) memoryInvertedIndex;
         BTree memBTree = memoryBTreeInvertedIndex.getBTree();
         InMemoryFreePageManager memFreePageManager = (InMemoryFreePageManager) memBTree.getFreePageManager();
         memFreePageManager.reset();
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexAccessor.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexAccessor.java
similarity index 96%
rename from hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexAccessor.java
rename to hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexAccessor.java
index d916de3..4baf6e2 100644
--- a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexAccessor.java
+++ b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexAccessor.java
@@ -1,4 +1,4 @@
-package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls;
+package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory;
 
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexCursorInitialState.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexCursorInitialState.java
similarity index 96%
rename from hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexCursorInitialState.java
rename to hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexCursorInitialState.java
index 2bf2f10..5495a4f 100644
--- a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexCursorInitialState.java
+++ b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexCursorInitialState.java
@@ -1,4 +1,4 @@
-package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls;
+package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory;
 
 import java.util.List;
 import java.util.concurrent.atomic.AtomicInteger;
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexFileManager.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexFileManager.java
similarity index 98%
rename from hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexFileManager.java
rename to hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexFileManager.java
index 2d4d0be..9ac0d7b 100644
--- a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexFileManager.java
+++ b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexFileManager.java
@@ -1,4 +1,4 @@
-package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls;
+package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory;
 
 import java.io.File;
 import java.io.FilenameFilter;
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexOpContext.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexOpContext.java
similarity index 91%
rename from hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexOpContext.java
rename to hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexOpContext.java
index 99f625c..e87c677 100644
--- a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexOpContext.java
+++ b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexOpContext.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls;
+package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory;
 
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
 import edu.uci.ics.hyracks.storage.am.common.api.IIndexOpContext;
@@ -29,7 +29,7 @@
     private final int tokenFieldCount;
     
     public LSMInvertedIndexOpContext(IInvertedIndex memoryInvertedIndex) {
-    	InMemoryBtreeInvertedIndex memoryBTreeInvertedIndex = (InMemoryBtreeInvertedIndex)memoryInvertedIndex;
+    	InMemoryInvertedIndex memoryBTreeInvertedIndex = (InMemoryInvertedIndex)memoryInvertedIndex;
     	BTree btree = memoryBTreeInvertedIndex.getBTree();
     	this.cmp = MultiComparator.create(btree.getComparatorFactories());
     	this.invListFieldCount = memoryBTreeInvertedIndex.getInvListCmpFactories().length;
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexRangeSearchCursor.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexRangeSearchCursor.java
similarity index 99%
rename from hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexRangeSearchCursor.java
rename to hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexRangeSearchCursor.java
index 657de5a..05d0380 100644
--- a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexRangeSearchCursor.java
+++ b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexRangeSearchCursor.java
@@ -1,4 +1,4 @@
-package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls;
+package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory;
 
 import java.util.ArrayList;
 import java.util.BitSet;
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexSearchCursor.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexSearchCursor.java
similarity index 98%
rename from hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexSearchCursor.java
rename to hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexSearchCursor.java
index c5c8645..73eef08 100644
--- a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/impls/LSMInvertedIndexSearchCursor.java
+++ b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/inmemory/LSMInvertedIndexSearchCursor.java
@@ -12,7 +12,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls;
+package edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory;
 
 import java.util.ArrayList;
 import java.util.List;
diff --git a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/utils/LSMInvertedIndexUtils.java b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/utils/LSMInvertedIndexUtils.java
index 25843ef..21691cf 100644
--- a/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/utils/LSMInvertedIndexUtils.java
+++ b/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/utils/LSMInvertedIndexUtils.java
@@ -4,7 +4,6 @@
 
 import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
 import edu.uci.ics.hyracks.api.dataflow.value.ITypeTraits;
-import edu.uci.ics.hyracks.control.nc.io.IOManager;
 import edu.uci.ics.hyracks.data.std.primitive.IntegerPointable;
 import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrameFactory;
 import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMLeafFrameFactory;
@@ -20,37 +19,26 @@
 import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.InMemoryBufferCache;
 import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.InMemoryFreePageManager;
 import edu.uci.ics.hyracks.storage.am.lsm.common.impls.BTreeFactory;
-import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls.InMemoryBtreeInvertedIndex;
-import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls.InvertedIndexFactory;
-import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls.LSMInvertedIndex;
-import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls.LSMInvertedIndexFileManager;
+import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory.InMemoryInvertedIndex;
+import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory.InvertedIndexFactory;
+import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory.LSMInvertedIndex;
+import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory.LSMInvertedIndexFileManager;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
 import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
 
 public class LSMInvertedIndexUtils {
-    public static InMemoryBtreeInvertedIndex createInMemoryBTreeInvertedindex(InMemoryBufferCache memBufferCache,
+    public static InMemoryInvertedIndex createInMemoryBTreeInvertedindex(InMemoryBufferCache memBufferCache,
             InMemoryFreePageManager memFreePageManager, ITypeTraits[] tokenTypeTraits, ITypeTraits[] invListTypeTraits,
             IBinaryComparatorFactory[] tokenCmpFactories, IBinaryComparatorFactory[] invListCmpFactories,
             IBinaryTokenizer tokenizer) {
-
-        // Create the BTree
-        int fieldCount = tokenCmpFactories.length + invListCmpFactories.length;
-        IBinaryComparatorFactory[] combinedFactories = concatArrays(tokenCmpFactories, invListCmpFactories);
-        ITypeTraits[] combinedTraits = concatArrays(tokenTypeTraits, invListTypeTraits);
-        ITreeIndexTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(combinedTraits);
-        ITreeIndexFrameFactory interiorFrameFactory = new BTreeNSMInteriorFrameFactory(tupleWriterFactory);
-        ITreeIndexFrameFactory leafFrameFactory = new BTreeNSMLeafFrameFactory(tupleWriterFactory);
-        BTree btree = new BTree(memBufferCache, fieldCount, combinedFactories, memFreePageManager,
-                interiorFrameFactory, leafFrameFactory);
-
-        return new InMemoryBtreeInvertedIndex(btree, invListTypeTraits, invListCmpFactories, tokenizer);
+        return new InMemoryInvertedIndex(btree, invListTypeTraits, invListCmpFactories, tokenizer);
     }
 
-    public static InvertedIndex createInvertedIndex(IBufferCache bufferCache, BTree btree, ITypeTraits[] invListFields,
-            IBinaryComparatorFactory[] invListCmpFactories, IBinaryTokenizer tokenizer) {
-
-        IInvertedListBuilder builder = new FixedSizeElementInvertedListBuilder(invListFields);
-        return new InvertedIndex(bufferCache, btree, invListFields, invListCmpFactories, builder, tokenizer);
+    public static InvertedIndex createInvertedIndex(IBufferCache bufferCache, IFileMapProvider fileMapProvider,
+            ITypeTraits[] invListTypeTraits, IBinaryComparatorFactory[] invListCmpFactories,
+            ITypeTraits[] tokenTypeTraits, IBinaryComparatorFactory[] tokenCmpFactories, IBinaryTokenizer tokenizer) {
+        IInvertedListBuilder builder = new FixedSizeElementInvertedListBuilder(invListTypeTraits);
+        return new InvertedIndex(bufferCache, fileMapProvider, invListTypeTraits, invListCmpFactories, tokenTypeTraits, tokenCmpFactories, builder, tokenizer);
     }
 
     public static LSMInvertedIndex createLSMInvertedIndex(InMemoryBufferCache memBufferCache,
@@ -59,7 +47,7 @@
             IBinaryTokenizer tokenizer, IBufferCache diskBufferCache,
             LinkedListFreePageManagerFactory diskFreePageManagerFactory, IOManager ioManager, String onDiskDir,
             IFileMapProvider diskFileMapProvider) {
-        InMemoryBtreeInvertedIndex memoryInvertedIndex = LSMInvertedIndexUtils.createInMemoryBTreeInvertedindex(
+        InMemoryInvertedIndex memoryInvertedIndex = LSMInvertedIndexUtils.createInMemoryBTreeInvertedindex(
                 memBufferCache, memFreePageManager, tokenTypeTraits, invListTypeTraits, tokenCmpFactories,
                 invListCmpFactories, tokenizer);
         ITypeTraits[] combinedTraits = concatArrays(tokenTypeTraits, new ITypeTraits[] { IntegerPointable.TYPE_TRAITS,
diff --git a/hyracks-storage-am-lsm-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/rtree/dataflow/AbstractLSMRTreeDataflowHelper.java b/hyracks-storage-am-lsm-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/rtree/dataflow/AbstractLSMRTreeDataflowHelper.java
index c7396de..244e07c 100644
--- a/hyracks-storage-am-lsm-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/rtree/dataflow/AbstractLSMRTreeDataflowHelper.java
+++ b/hyracks-storage-am-lsm-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/rtree/dataflow/AbstractLSMRTreeDataflowHelper.java
@@ -33,8 +33,8 @@
 import edu.uci.ics.hyracks.storage.am.lsm.common.api.ILSMOperationTracker;
 import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.InMemoryBufferCache;
 import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.InMemoryFreePageManager;
-import edu.uci.ics.hyracks.storage.am.lsm.rtree.impls.LSMRTreeInMemoryBufferCache;
-import edu.uci.ics.hyracks.storage.am.lsm.rtree.impls.LSMRTreeInMemoryFreePageManager;
+import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.DualIndexInMemoryBufferCache;
+import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.DualIndexInMemoryFreePageManager;
 import edu.uci.ics.hyracks.storage.am.rtree.frames.RTreePolicyType;
 import edu.uci.ics.hyracks.storage.common.buffercache.HeapBufferAllocator;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
@@ -84,9 +84,9 @@
     @Override
     public ITreeIndex getIndexInstance() throws HyracksDataException {
         ITreeIndexMetaDataFrameFactory metaDataFrameFactory = new LIFOMetaDataFrameFactory();
-        InMemoryBufferCache memBufferCache = new LSMRTreeInMemoryBufferCache(new HeapBufferAllocator(), memPageSize,
+        InMemoryBufferCache memBufferCache = new DualIndexInMemoryBufferCache(new HeapBufferAllocator(), memPageSize,
                 memNumPages);
-        InMemoryFreePageManager memFreePageManager = new LSMRTreeInMemoryFreePageManager(memNumPages,
+        InMemoryFreePageManager memFreePageManager = new DualIndexInMemoryFreePageManager(memNumPages,
                 metaDataFrameFactory);
 
         return createLSMTree(memBufferCache, memFreePageManager, ctx.getIOManager(), file, opDesc.getStorageManager()
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeSearchOperatorNodePushable.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeSearchOperatorNodePushable.java
index 3781037..6ac7964 100644
--- a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeSearchOperatorNodePushable.java
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeSearchOperatorNodePushable.java
@@ -20,9 +20,9 @@
 import edu.uci.ics.hyracks.storage.am.common.api.IOperationCallbackProvider;
 import edu.uci.ics.hyracks.storage.am.common.api.ISearchPredicate;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.AbstractTreeIndexOperatorDescriptor;
-import edu.uci.ics.hyracks.storage.am.common.dataflow.PermutingFrameTupleReference;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexSearchOperatorNodePushable;
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.tuples.PermutingFrameTupleReference;
 import edu.uci.ics.hyracks.storage.am.rtree.impls.SearchPredicate;
 import edu.uci.ics.hyracks.storage.am.rtree.util.RTreeUtils;
 
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/AbstractInvIndexSearchTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/AbstractInvIndexSearchTest.java
index ee954d3..32566d8 100644
--- a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/AbstractInvIndexSearchTest.java
+++ b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/AbstractInvIndexSearchTest.java
@@ -58,6 +58,7 @@
     protected IFileMapProvider fmp;
 
     protected FileReference invListsFile = new FileReference(new File(invListsFileName));
+    protected FileReference btreeFile = new FileReference(new File(invListsFileName + "_btree"));
 
     protected ITypeTraits[] tokenTypeTraits = new ITypeTraits[] { UTF8StringPointable.TYPE_TRAITS };
     protected IBinaryComparatorFactory[] tokenCmpFactories = new IBinaryComparatorFactory[] { PointableBinaryComparatorFactory
@@ -109,7 +110,7 @@
 
         IInvertedListBuilder invListBuilder = new FixedSizeElementInvertedListBuilder(invListTypeTraits);
         invIndex = new InvertedIndex(bufferCache, fmp, invListBuilder, invListTypeTraits, invListCmpFactories,
-                tokenTypeTraits, tokenCmpFactories, invListsFile);
+                tokenTypeTraits, tokenCmpFactories, invListsFile, btreeFile);
         invIndex.create();
         invIndex.activate();
 
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/BulkLoadTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/BulkLoadTest.java
index 5b15789..2e03cbc 100644
--- a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/BulkLoadTest.java
+++ b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/BulkLoadTest.java
@@ -50,12 +50,14 @@
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexAccessor;
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
 import edu.uci.ics.hyracks.storage.am.common.impls.NoOpOperationCallback;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListBuilder;
 import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListCursor;
 import edu.uci.ics.hyracks.storage.am.invertedindex.impls.FixedSizeElementInvertedListBuilder;
 import edu.uci.ics.hyracks.storage.am.invertedindex.impls.FixedSizeElementInvertedListCursor;
 import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndex;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndexOpContext;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
 import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
 import edu.uci.ics.hyracks.test.support.TestStorageManagerComponentHolder;
@@ -82,6 +84,7 @@
         IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(stageletCtx);
 
         FileReference invListsFile = new FileReference(new File(invListsFileName));
+        FileReference btreeFile = new FileReference(new File(invListsFileName + "_btree"));
 
         ITypeTraits[] tokenTypeTraits = new ITypeTraits[] { UTF8StringPointable.TYPE_TRAITS };
 
@@ -98,7 +101,7 @@
 
         IInvertedListBuilder invListBuilder = new FixedSizeElementInvertedListBuilder(invListTypeTraits);
         InvertedIndex invIndex = new InvertedIndex(bufferCache, fmp, invListBuilder, invListTypeTraits,
-                invListCmpFactories, tokenTypeTraits, cmpFactories, invListsFile);
+                invListCmpFactories, tokenTypeTraits, cmpFactories, invListsFile, btreeFile);
         invIndex.create();
         invIndex.activate();
 
@@ -189,6 +192,8 @@
         tokenAccessor.reset(frame);
 
         // verify created inverted lists one-by-one
+        InvertedIndexOpContext opCtx = new InvertedIndexOpContext(invIndex.getBTree());
+        opCtx.reset(IndexOp.SEARCH);
         for (int i = 0; i < tokens.size(); i++) {
 
             tokenTupleBuilder.reset();
@@ -201,9 +206,9 @@
 
             searchKey.reset(tokenAccessor, 0);
 
-            invIndex.openCursor(btreeCursor, btreePred, btreeAccessor, invListCursor);
+            invIndex.openInvertedListCursor(invListCursor, searchKey, opCtx);
 
-            invListCursor.pinPagesSync();
+            invListCursor.pinPages();
             int checkIndex = 0;
             while (invListCursor.hasNext()) {
                 invListCursor.next();
@@ -236,9 +241,9 @@
 
             searchKey.reset(tokenAccessor, 0);
 
-            invIndex.openCursor(btreeCursor, btreePred, btreeAccessor, invListCursor);
-
-            invListCursor.pinPagesSync();
+            invIndex.openInvertedListCursor(invListCursor, searchKey, opCtx);
+            
+            invListCursor.pinPages();
             Assert.assertEquals(invListCursor.hasNext(), false);
             invListCursor.unpinPages();
         }
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/InvertedIndexLifecycleTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/InvertedIndexLifecycleTest.java
index 4402017..ae90520 100644
--- a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/InvertedIndexLifecycleTest.java
+++ b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/InvertedIndexLifecycleTest.java
@@ -18,7 +18,7 @@
 
     @Override
     protected boolean persistentStateExists() throws Exception {
-        return harness.getFileReference().getFile().exists()
+        return harness.getInvListsFile().getFile().exists()
                 && ((InvertedIndex) index).getBTree().getFileReference().getFile().exists();
     }
 
@@ -41,7 +41,8 @@
                 .of(IntegerPointable.FACTORY) };
         IInvertedListBuilder invListBuilder = new FixedSizeElementInvertedListBuilder(invListTypeTraits);
         index = new InvertedIndex(harness.getBufferCache(), harness.getFileMapProvider(), invListBuilder,
-                invListTypeTraits, invListCmpFactories, tokenTypeTraits, tokenCmpFactories, harness.getFileReference());
+                invListTypeTraits, invListCmpFactories, tokenTypeTraits, tokenCmpFactories, harness.getInvListsFile(),
+                harness.getBTreeFile());
 
     }
 
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/InvertedIndexTestHarness.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/InvertedIndexTestHarness.java
index dd2f38a..aa7aeab 100644
--- a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/InvertedIndexTestHarness.java
+++ b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/InvertedIndexTestHarness.java
@@ -25,7 +25,8 @@
     private IHyracksTaskContext ctx;
     private IBufferCache bufferCache;
     private IFileMapProvider fileMapProvider;
-    private FileReference file;
+    private FileReference invListsFile;
+    private FileReference btreeFile;
 
     private final Random rnd = new Random();
     private final SimpleDateFormat simpleDateFormat = new SimpleDateFormat("ddMMyy-hhmmssSS");
@@ -51,13 +52,14 @@
         TestStorageManagerComponentHolder.init(pageSize, numPages, maxOpenFiles);
         bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
         fileMapProvider = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
-        file = new FileReference(new File(fileName));
+        invListsFile = new FileReference(new File(fileName));
+        btreeFile = new FileReference(new File(fileName + "_btree"));
         rnd.setSeed(RANDOM_SEED);
     }
 
     public void tearDown() throws HyracksDataException {
         bufferCache.close();
-        file.delete();
+        invListsFile.delete();
     }
 
     public IHyracksTaskContext getHyracksTaskContext() {
@@ -72,8 +74,12 @@
         return fileMapProvider;
     }
 
-    public FileReference getFileReference() {
-        return file;
+    public FileReference getInvListsFile() {
+        return invListsFile;
+    }
+    
+    public FileReference getBTreeFile() {
+        return btreeFile;
     }
 
     public String getFileName() {
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/SearchTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/SearchTest.java
index 1c23f72..e49283e 100644
--- a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/SearchTest.java
+++ b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/SearchTest.java
@@ -135,7 +135,7 @@
 
     public void loadData() throws IOException, IndexException {
         List<TokenIdPair> pairs = new ArrayList<TokenIdPair>();
-        // generate pairs for subsequent sorting and bulk-loading
+        // Generate pairs for subsequent sorting and bulk-loading.
         int id = 0;
         for (String s : dataStrings) {
             ByteArrayAccessibleOutputStream baaos = new ByteArrayAccessibleOutputStream();
@@ -151,7 +151,7 @@
         }
         Collections.sort(pairs);
 
-        // bulk load index
+        // Bulk load index.
         IIndexBulkLoader bulkLoader = invIndex.createBulkLoader(BTree.DEFAULT_FILL_FACTOR, false);
 
         for (TokenIdPair t : pairs) {
diff --git a/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/utils/InvertedIndexTestUtils.java b/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/utils/InvertedIndexTestUtils.java
index 7152a9a..8ed93d1 100644
--- a/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/utils/InvertedIndexTestUtils.java
+++ b/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/utils/InvertedIndexTestUtils.java
@@ -1,3 +1,18 @@
+/*
+ * Copyright 2009-2010 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.hyracks.storage.am.lsm.invertedindex.utils;
 
 import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
@@ -19,8 +34,8 @@
 import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriterFactory;
 import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndex;
 import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IBinaryTokenizer;
-import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls.InMemoryBtreeInvertedIndex;
-import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls.LSMInvertedIndex;
+import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory.InMemoryInvertedIndex;
+import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.inmemory.LSMInvertedIndex;
 import edu.uci.ics.hyracks.storage.am.lsm.inverteredindex.LSMInvertedIndexTestHarness;
 
 public class InvertedIndexTestUtils {
@@ -37,15 +52,11 @@
                 metaFrameFactory);
         IBinaryComparatorFactory[] btreeCmpFactories = new IBinaryComparatorFactory[] { PointableBinaryComparatorFactory
                 .of(UTF8StringPointable.FACTORY) };
-        BTree btree = new BTree(harness.getDiskBufferCache(), 5, btreeCmpFactories, freePageManager,
-                interiorFrameFactory, leafFrameFactory);
-        btree.create(harness.getDiskBtreeFileId());
-        btree.open(harness.getDiskBtreeFileId());
-        return LSMInvertedIndexUtils.createInvertedIndex(harness.getDiskBufferCache(), btree,
+        return LSMInvertedIndexUtils.createInvertedIndex(harness.getDiskBufferCache(), 
                 harness.getInvertedListTypeTraits(), harness.getInvertedListBinaryComparatorFactories(), tokenizer);
     }
 
-    public static InMemoryBtreeInvertedIndex createTestInMemoryBTreeInvertedIndex(LSMInvertedIndexTestHarness harness,
+    public static InMemoryInvertedIndex createInMemoryInvertedIndex(LSMInvertedIndexTestHarness harness,
             IBinaryTokenizer tokenizer) {
         return LSMInvertedIndexUtils.createInMemoryBTreeInvertedindex(harness.getMemBufferCache(),
                 harness.getMemFreePageManager(), harness.getTokenTypeTraits(), harness.getInvertedListTypeTraits(),
diff --git a/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/inverteredindex/AbstractInvertedIndexTest.java b/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/inverteredindex/AbstractInvertedIndexTest.java
index 8fdf67e..06d2659 100644
--- a/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/inverteredindex/AbstractInvertedIndexTest.java
+++ b/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/inverteredindex/AbstractInvertedIndexTest.java
@@ -25,9 +25,9 @@
 import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.api.exceptions.HyracksException;
+import edu.uci.ics.hyracks.data.std.util.ByteArrayAccessibleOutputStream;
 import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
 import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleReference;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.ByteArrayAccessibleOutputStream;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
@@ -43,7 +43,6 @@
 import edu.uci.ics.hyracks.storage.am.invertedindex.searchmodifiers.ConjunctiveSearchModifier;
 import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IBinaryTokenizer;
 import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IToken;
-import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.impls.LSMInvertedIndexAccessor;
 
 public abstract class AbstractInvertedIndexTest {
     protected Logger LOGGER;
@@ -78,6 +77,8 @@
         harness.setUp();
         setTokenizer();
         setInvertedIndex();
+        invertedIndex.create();
+        invertedIndex.activate();
         setLogger();
         setRandom();
         generateData();
@@ -261,7 +262,7 @@
         // Query all tokens in the baseline
 
         ConjunctiveSearchModifier searchModifier = new ConjunctiveSearchModifier();
-        InvertedIndexSearchPredicate searchPred = new InvertedIndexSearchPredicate(searchModifier);
+        InvertedIndexSearchPredicate searchPred = new InvertedIndexSearchPredicate(tokenizer, searchModifier);
         IIndexCursor resultCursor = invertedIndexAccessor.createSearchCursor();
         for (String tokenStr : baselineInvertedIndex.keySet()) {
             tuple = TupleUtils.createTuple(new ISerializerDeserializer[] { UTF8StringSerializerDeserializer.INSTANCE },
diff --git a/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/inverteredindex/InMemoryBTreeInvertedIndexInsertTest.java b/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/inverteredindex/InMemoryBTreeInvertedIndexInsertTest.java
index 1a1a7cc..8e5df91 100644
--- a/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/inverteredindex/InMemoryBTreeInvertedIndexInsertTest.java
+++ b/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/inverteredindex/InMemoryBTreeInvertedIndexInsertTest.java
@@ -20,7 +20,9 @@
 
     @Override
     protected void setInvertedIndex() throws HyracksDataException {
-        invertedIndex = InvertedIndexTestUtils.createTestInMemoryBTreeInvertedIndex(harness, tokenizer);
+        invertedIndex = InvertedIndexTestUtils.createInMemoryInvertedIndex(harness, tokenizer);
+        invertedIndex.create();
+        invertedIndex.activate();
         invertedIndex.create(harness.getFileId());
         invertedIndex.open(harness.getFileId());
     }
diff --git a/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/inverteredindex/InMemoryBTreeInvertedIndexSearchTest.java b/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/inverteredindex/InMemoryBTreeInvertedIndexSearchTest.java
index 99dc654..e0ac81a 100644
--- a/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/inverteredindex/InMemoryBTreeInvertedIndexSearchTest.java
+++ b/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/inverteredindex/InMemoryBTreeInvertedIndexSearchTest.java
@@ -92,7 +92,7 @@
 
     @Override
     protected void setInvertedIndex() throws HyracksDataException {
-        invertedIndex = InvertedIndexTestUtils.createTestInMemoryBTreeInvertedIndex(harness, tokenizer);
+        invertedIndex = InvertedIndexTestUtils.createInMemoryInvertedIndex(harness, tokenizer);
         invertedIndex.create(harness.getFileId());
         invertedIndex.open(harness.getFileId());
     }
diff --git a/hyracks-tests/hyracks-storage-am-lsm-rtree-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/rtree/util/LSMRTreeTestHarness.java b/hyracks-tests/hyracks-storage-am-lsm-rtree-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/rtree/util/LSMRTreeTestHarness.java
index 8d60923..4de1344 100644
--- a/hyracks-tests/hyracks-storage-am-lsm-rtree-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/rtree/util/LSMRTreeTestHarness.java
+++ b/hyracks-tests/hyracks-storage-am-lsm-rtree-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/rtree/util/LSMRTreeTestHarness.java
@@ -36,12 +36,12 @@
 import edu.uci.ics.hyracks.storage.am.lsm.common.api.ILSMOperationTracker;
 import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.InMemoryBufferCache;
 import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.InMemoryFreePageManager;
+import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.DualIndexInMemoryBufferCache;
+import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.DualIndexInMemoryFreePageManager;
 import edu.uci.ics.hyracks.storage.am.lsm.common.impls.FlushController;
 import edu.uci.ics.hyracks.storage.am.lsm.common.impls.ImmediateScheduler;
 import edu.uci.ics.hyracks.storage.am.lsm.common.impls.NoMergePolicy;
 import edu.uci.ics.hyracks.storage.am.lsm.common.impls.RefCountingOperationTracker;
-import edu.uci.ics.hyracks.storage.am.lsm.rtree.impls.LSMRTreeInMemoryBufferCache;
-import edu.uci.ics.hyracks.storage.am.lsm.rtree.impls.LSMRTreeInMemoryFreePageManager;
 import edu.uci.ics.hyracks.storage.common.buffercache.HeapBufferAllocator;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
 import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
@@ -64,8 +64,8 @@
     protected IOManager ioManager;
     protected IBufferCache diskBufferCache;
     protected IFileMapProvider diskFileMapProvider;
-    protected LSMRTreeInMemoryBufferCache memBufferCache;
-    protected LSMRTreeInMemoryFreePageManager memFreePageManager;
+    protected DualIndexInMemoryBufferCache memBufferCache;
+    protected DualIndexInMemoryFreePageManager memFreePageManager;
     protected IHyracksTaskContext ctx;
     protected ILSMIOOperationScheduler ioScheduler;
     protected ILSMFlushController flushController;
@@ -112,8 +112,8 @@
         TestStorageManagerComponentHolder.init(diskPageSize, diskNumPages, diskMaxOpenFiles);
         diskBufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
         diskFileMapProvider = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
-        memBufferCache = new LSMRTreeInMemoryBufferCache(new HeapBufferAllocator(), memPageSize, memNumPages);
-        memFreePageManager = new LSMRTreeInMemoryFreePageManager(memNumPages, new LIFOMetaDataFrameFactory());
+        memBufferCache = new DualIndexInMemoryBufferCache(new HeapBufferAllocator(), memPageSize, memNumPages);
+        memFreePageManager = new DualIndexInMemoryFreePageManager(memNumPages, new LIFOMetaDataFrameFactory());
         ioManager = TestStorageManagerComponentHolder.getIOManager();
         rnd.setSeed(RANDOM_SEED);
     }