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 b8115b3..3044e48 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
@@ -68,14 +68,13 @@
     protected ICachedPage page = null;
     protected ByteBuffer buf = null;
 
-    private final int fieldCount;
-    
     public ITreeIndexFrameCompressor compressor;
     // TODO: Should be protected, but will trigger some refactoring.
     public IPrefixSlotManager slotManager;
 
     private ITreeIndexTupleWriter tupleWriter;
-
+    private MultiComparator cmp;
+    
     private FieldPrefixTupleReference frameTuple;
     private FieldPrefixPrefixTupleReference framePrefixTuple;
 
@@ -83,9 +82,9 @@
         this.tupleWriter = tupleWriter;
         this.frameTuple = new FieldPrefixTupleReference(tupleWriter.createTupleReference());
         ITypeTrait[] typeTraits = ((TypeAwareTupleWriter) tupleWriter).getTypeTraits();
-        this.fieldCount = typeTraits.length;
         this.framePrefixTuple = new FieldPrefixPrefixTupleReference(typeTraits);
         this.slotManager = new FieldPrefixSlotManager(cmp);
+        this.cmp = cmp;
         this.compressor = new FieldPrefixCompressor(typeTraits, 0.001f, 2);
     }
 
@@ -107,7 +106,7 @@
     }
 
     @Override
-    public boolean compress(MultiComparator cmp) throws HyracksDataException {
+    public boolean compress() throws HyracksDataException {
         try {
             return compressor.compress(this, cmp);
         } catch (Exception e) {
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 faa7373..30149ab 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
@@ -330,7 +330,7 @@
             }
             case INSUFFICIENT_SPACE: {
                 // Try compressing the page first and see if there is space available.
-                boolean reCompressed = ctx.leafFrame.compress(cmp);
+                boolean reCompressed = ctx.leafFrame.compress();
                 if (reCompressed) {
                     // Compression could have changed the target tuple index, find it again.
                     targetTupleIndex = ctx.leafFrame.findInsertTupleIndex(tuple, cmp);
@@ -445,7 +445,7 @@
             case INSUFFICIENT_SPACE: {
                 // Delete the old tuple, and try compressing the page to make space available.
                 ctx.leafFrame.delete(tuple, oldTupleIndex);
-                ctx.leafFrame.compress(cmp);
+                ctx.leafFrame.compress();
                 // We need to insert the new tuple, so check if there is space.
                 spaceStatus = ctx.leafFrame.hasSpaceInsert(tuple);                
                 if (spaceStatus == FrameOpSpaceStatus.SUFFICIENT_CONTIGUOUS_SPACE) {
@@ -947,7 +947,7 @@
 
         // try to free space by compression
         if (spaceUsed + spaceNeeded > ctx.leafMaxBytes) {
-            leafFrame.compress(cmp);
+            leafFrame.compress();
             spaceUsed = leafFrame.getBuffer().capacity() - leafFrame.getTotalFreeSpace();
         }
 
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexFrame.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexFrame.java
index dda2f59..fc247d7 100644
--- a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexFrame.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexFrame.java
@@ -39,7 +39,7 @@
     // returns true if slots were modified, false otherwise
     public boolean compact();
 
-    public boolean compress(MultiComparator cmp) throws HyracksDataException;
+    public boolean compress() throws HyracksDataException;
 
     public void initBuffer(byte level);
 
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 82d622c..574456e 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
@@ -291,7 +291,7 @@
     }
 
     @Override
-    public boolean compress(MultiComparator cmp) {
+    public boolean compress() {
         return false;
     }
 
diff --git a/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeFieldPrefixNSMTest.java b/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeFieldPrefixNSMTest.java
index 14e85e9..73b25c1 100644
--- a/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeFieldPrefixNSMTest.java
+++ b/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeFieldPrefixNSMTest.java
@@ -163,7 +163,7 @@
 
                 if (rnd.nextInt() % compressFreq == 0) {
                     before = frame.printKeys(cmp, sers);
-                    frame.compress(cmp);
+                    frame.compress();
                     after = frame.printKeys(cmp, sers);
                     Assert.assertEquals(before, after);
                 }
@@ -192,7 +192,7 @@
 
                 if (rnd.nextInt() % compressFreq == 0) {
                     before = frame.printKeys(cmp, sers);
-                    frame.compress(cmp);
+                    frame.compress();
                     after = frame.printKeys(cmp, sers);
                     Assert.assertEquals(before, after);
                 }