diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/compressors/FieldPrefixCompressor.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/compressors/FieldPrefixCompressor.java
index c897adb..c0a46a7 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/compressors/FieldPrefixCompressor.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/compressors/FieldPrefixCompressor.java
@@ -21,19 +21,17 @@
 import java.util.Comparator;
 
 import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
-import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
 import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
-import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
-import edu.uci.ics.hyracks.storage.am.btree.api.IFrameCompressor;
 import edu.uci.ics.hyracks.storage.am.btree.api.IPrefixSlotManager;
 import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeFieldPrefixNSMLeafFrame;
 import edu.uci.ics.hyracks.storage.am.btree.impls.FieldPrefixSlotManager;
 import edu.uci.ics.hyracks.storage.am.btree.impls.FieldPrefixTupleReference;
-import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameCompressor;
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriter;
 
-public class FieldPrefixCompressor implements IFrameCompressor {
+public class FieldPrefixCompressor implements ITreeIndexFrameCompressor {
 
     // minimum ratio of uncompressed tuples to total tuple to consider
     // re-compression
@@ -52,8 +50,9 @@
     }
 
     @Override
-    public boolean compress(BTreeFieldPrefixNSMLeafFrame frame, MultiComparator cmp) throws Exception {
-        int tupleCount = frame.getTupleCount();
+    public boolean compress(ITreeIndexFrame indexFrame, MultiComparator cmp) throws Exception {
+        BTreeFieldPrefixNSMLeafFrame frame = (BTreeFieldPrefixNSMLeafFrame)indexFrame;
+    	int tupleCount = frame.getTupleCount();
         if (tupleCount <= 0) {
             frame.setPrefixTupleCount(0);
             frame.setFreeSpaceOff(frame.getOrigFreeSpaceOff());
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeFieldPrefixNSMLeafFrame.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeFieldPrefixNSMLeafFrame.java
index 0ad8b68..ead9feb 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeFieldPrefixNSMLeafFrame.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeFieldPrefixNSMLeafFrame.java
@@ -27,7 +27,6 @@
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IFrameCompressor;
 import edu.uci.ics.hyracks.storage.am.btree.api.IPrefixSlotManager;
 import edu.uci.ics.hyracks.storage.am.btree.compressors.FieldPrefixCompressor;
 import edu.uci.ics.hyracks.storage.am.btree.exceptions.BTreeDuplicateKeyException;
@@ -38,6 +37,7 @@
 import edu.uci.ics.hyracks.storage.am.common.api.ISlotManager;
 import edu.uci.ics.hyracks.storage.am.common.api.ISplitKey;
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameCompressor;
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
 import edu.uci.ics.hyracks.storage.am.common.api.TreeIndexException;
@@ -67,7 +67,7 @@
 
     protected ICachedPage page = null;
     protected ByteBuffer buf = null;
-    public IFrameCompressor compressor;
+    public ITreeIndexFrameCompressor compressor;
     // TODO: Should be protected, but will trigger some refactoring.
     public IPrefixSlotManager slotManager;
 
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMInteriorFrame.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMInteriorFrame.java
index 93b7ea7..ddf056d 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMInteriorFrame.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMInteriorFrame.java
@@ -26,8 +26,6 @@
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrame;
-import edu.uci.ics.hyracks.storage.am.btree.exceptions.BTreeDuplicateKeyException;
-import edu.uci.ics.hyracks.storage.am.btree.exceptions.BTreeNonExistentKeyException;
 import edu.uci.ics.hyracks.storage.am.btree.impls.RangePredicate;
 import edu.uci.ics.hyracks.storage.am.common.api.ISplitKey;
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
@@ -44,16 +42,14 @@
 public class BTreeNSMInteriorFrame extends TreeIndexNSMFrame implements IBTreeInteriorFrame {
 
     private static final int rightLeafOff = smFlagOff + 1;
-
     private static final int childPtrSize = 4;
 
     // private SimpleTupleReference cmpFrameTuple = new SimpleTupleReference();
     private ITreeIndexTupleReference cmpFrameTuple;
 
-    public BTreeNSMInteriorFrame(ITreeIndexTupleWriter tupleWriter) {
-        super(tupleWriter, new OrderedSlotManager());
+    public BTreeNSMInteriorFrame(ITreeIndexTupleWriter tupleWriter) {        
+    	super(tupleWriter, new OrderedSlotManager());
         cmpFrameTuple = tupleWriter.createTupleReference();
-
     }
 
     private int getLeftChildPageOff(ITupleReference tuple, MultiComparator cmp) {
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 9a47d7b..1b909bb 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
@@ -202,17 +202,14 @@
         // make sure the root is always at the same level
         ICachedPage leftNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, ctx.splitKey.getLeftPage()),
                 false);
-        // TODO: Think about whether latching is really required.
         leftNode.acquireWriteLatch();
         try {
             ICachedPage rightNode = bufferCache.pin(
                     BufferedFileHandle.getDiskPageId(fileId, ctx.splitKey.getRightPage()), false);
-            // TODO: Think about whether latching is really required.
             rightNode.acquireWriteLatch();
             try {
                 int newLeftId = freePageManager.getFreePage(ctx.metaFrame);
                 ICachedPage newLeftNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, newLeftId), true);
-                // TODO: Think about whether latching is really required.
                 newLeftNode.acquireWriteLatch();
                 try {
                     // copy left child to new left child
@@ -527,9 +524,7 @@
     // TODO: to avoid latch deadlock, must modify cursor to detect empty leaves
     private void deleteLeaf(ICachedPage node, int pageId, ITupleReference tuple, BTreeOpContext ctx) throws Exception {
         ctx.leafFrame.setPage(node);
-
         int tupleIndex = ctx.leafFrame.findDeleteTupleIndex(tuple, cmp);
-        
         // Will this leaf become empty?
         if (ctx.leafFrame.getTupleCount() == 1) {
             IBTreeLeafFrame siblingFrame = (IBTreeLeafFrame) leafFrameFactory.createFrame();
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ISlotManager.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ISlotManager.java
index 93f3cf0..afdfb7c 100644
--- a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ISlotManager.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ISlotManager.java
@@ -21,8 +21,6 @@
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
 public interface ISlotManager {
-	public void setFrame(ITreeIndexFrame frame);
-
 	public int findTupleIndex(ITupleReference searchKey,
 			ITreeIndexTupleReference frameTuple, MultiComparator multiCmp,
 			FindTupleMode mode, FindTupleNoExactMatchPolicy matchPolicy);
@@ -30,6 +28,8 @@
 	public boolean isHighestTupleIndex(int tupleIndex);
 	
 	public boolean isErrorTupleIndex(int tupleIndex);
+
+	public void setFrame(ITreeIndexFrame frame);
 	
 	public int insertSlot(int tupleIndex, int tupleOff);
 
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IFrameCompressor.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexFrameCompressor.java
similarity index 72%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IFrameCompressor.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexFrameCompressor.java
index 8e1d0a2..75ee598 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IFrameCompressor.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexFrameCompressor.java
@@ -13,11 +13,10 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.api;
+package edu.uci.ics.hyracks.storage.am.common.api;
 
-import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeFieldPrefixNSMLeafFrame;
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
-public interface IFrameCompressor {
-    public boolean compress(BTreeFieldPrefixNSMLeafFrame frame, MultiComparator cmp) throws Exception;
+public interface ITreeIndexFrameCompressor {
+    public boolean compress(ITreeIndexFrame frame, MultiComparator cmp) throws Exception;
 }
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/TreeIndexNSMFrame.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/TreeIndexNSMFrame.java
index e9f5ebc..910db84 100644
--- a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/TreeIndexNSMFrame.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/TreeIndexNSMFrame.java
@@ -53,6 +53,7 @@
         this.tupleWriter = tupleWriter;
         this.frameTuple = tupleWriter.createTupleReference();
         this.slotManager = slotManager;
+        this.slotManager.setFrame(this);
     }
 
     @Override
@@ -112,7 +113,6 @@
     public void setPage(ICachedPage page) {
         this.page = page;
         this.buf = page.getBuffer();
-        slotManager.setFrame(this);
     }
 
     @Override