diff --git a/hyracks/hyracks-dataflow-std/src/main/java/org/apache/hyracks/dataflow/std/structures/AbstractHeap.java b/hyracks/hyracks-dataflow-std/src/main/java/org/apache/hyracks/dataflow/std/structures/AbstractHeap.java
index a0abaf7..c6ca09b 100644
--- a/hyracks/hyracks-dataflow-std/src/main/java/org/apache/hyracks/dataflow/std/structures/AbstractHeap.java
+++ b/hyracks/hyracks-dataflow-std/src/main/java/org/apache/hyracks/dataflow/std/structures/AbstractHeap.java
@@ -21,7 +21,7 @@
 
 import java.util.Arrays;
 
-import org.apache.hyracks.dataflow.std.util.MathUtil;
+import org.apache.hyracks.util.MathUtil;
 
 public abstract class AbstractHeap implements IHeap<IResetableComparable> {
     protected static final int NOT_EXIST = -1;
diff --git a/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/datagen/DocumentStringFieldValueGenerator.java b/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/datagen/DocumentStringFieldValueGenerator.java
index cff11dc..1e8077c 100644
--- a/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/datagen/DocumentStringFieldValueGenerator.java
+++ b/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/datagen/DocumentStringFieldValueGenerator.java
@@ -27,6 +27,8 @@
 import java.util.List;
 import java.util.Random;
 
+import org.apache.hyracks.util.MathUtil;
+
 public class DocumentStringFieldValueGenerator implements IFieldValueGenerator<String> {
     private final String FIRST_NAMES_FILE = "dist.all.first.cleaned";
     private final String LAST_NAMES_FILE = "dist.all.last.cleaned";
@@ -82,7 +84,7 @@
     @Override
     public String next() {
         StringBuilder strBuilder = new StringBuilder();
-        int numWords = Math.abs(rnd.nextInt()) % (docMaxWords - docMinWords + 1) + docMinWords;
+        int numWords = MathUtil.stripSignBit(rnd.nextInt()) % (docMaxWords - docMinWords + 1) + docMinWords;
         for (int i = 0; i < numWords; i++) {
             int ix = ProbabilityHelper.choose(cumulIntRanges, rnd.nextInt());
             strBuilder.append(tokenDict.get(ix));
diff --git a/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/datagen/PersonNameFieldValueGenerator.java b/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/datagen/PersonNameFieldValueGenerator.java
index 49edafb..5af0b0f 100644
--- a/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/datagen/PersonNameFieldValueGenerator.java
+++ b/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/datagen/PersonNameFieldValueGenerator.java
@@ -27,6 +27,8 @@
 import java.util.List;
 import java.util.Random;
 
+import org.apache.hyracks.util.MathUtil;
+
 public class PersonNameFieldValueGenerator implements IFieldValueGenerator<String> {
     private final String FIRST_NAMES_FILE = "dist.all.first.cleaned";
     private final String LAST_NAMES_FILE = "dist.all.last.cleaned";
@@ -76,20 +78,20 @@
         StringBuilder strBuilder = new StringBuilder();
 
         // First name.
-        int fix = Math.abs(rnd.nextInt()) % firstNames.size();
+        int fix = MathUtil.stripSignBit(rnd.nextInt()) % firstNames.size();
         strBuilder.append(firstNames.get(fix));
         strBuilder.append(" ");
 
         // Optional middle initial.
         double d = Math.abs(rnd.nextDouble());
         if (d <= middleInitialProb) {
-            int mix = Math.abs(rnd.nextInt()) % letters.length();
+            int mix = MathUtil.stripSignBit(rnd.nextInt()) % letters.length();
             strBuilder.append(letters.charAt(mix));
             strBuilder.append(". ");
         }
 
         // Last name.
-        int lix = Math.abs(rnd.nextInt()) % lastNames.size();
+        int lix = MathUtil.stripSignBit(rnd.nextInt()) % lastNames.size();
         strBuilder.append(lastNames.get(lix));
 
         return strBuilder.toString();
diff --git a/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/datagen/StringFieldValueGenerator.java b/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/datagen/StringFieldValueGenerator.java
index c337462..9418447 100644
--- a/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/datagen/StringFieldValueGenerator.java
+++ b/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/datagen/StringFieldValueGenerator.java
@@ -21,6 +21,8 @@
 
 import java.util.Random;
 
+import org.apache.hyracks.util.MathUtil;
+
 public class StringFieldValueGenerator implements IFieldValueGenerator<String> {
     private int maxLen;
     private final Random rnd;
@@ -39,7 +41,7 @@
         String s = Long.toHexString(Double.doubleToLongBits(rnd.nextDouble()));
         StringBuilder strBuilder = new StringBuilder();
         for (int i = 0; i < s.length() && i < maxLen; i++) {
-            strBuilder.append(s.charAt(Math.abs(rnd.nextInt()) % s.length()));
+            strBuilder.append(s.charAt(MathUtil.stripSignBit(rnd.nextInt()) % s.length()));
         }
         return strBuilder.toString();
     }
diff --git a/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/util/TreeIndexBufferCacheWarmup.java b/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/util/TreeIndexBufferCacheWarmup.java
index 398a3f3..d9013d3 100644
--- a/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/util/TreeIndexBufferCacheWarmup.java
+++ b/hyracks/hyracks-storage-am-common/src/main/java/org/apache/hyracks/storage/am/common/util/TreeIndexBufferCacheWarmup.java
@@ -22,6 +22,7 @@
 import java.util.Random;
 
 import org.apache.hyracks.api.exceptions.HyracksDataException;
+import org.apache.hyracks.util.MathUtil;
 import org.apache.hyracks.storage.am.common.api.IMetaDataPageManager;
 import org.apache.hyracks.storage.am.common.api.ITreeIndexFrame;
 import org.apache.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
@@ -84,7 +85,7 @@
 
 					int remainingLength = pageIds.size();
 					for (int j = 0; j < pageIds.size(); j++) {
-						int index = Math.abs(rnd.nextInt()) % remainingLength;
+						int index = MathUtil.stripSignBit(rnd.nextInt()) % remainingLength;
 						int pageId = remainingPageIds[index];
 
 						// pin & latch then immediately unlatch & unpin
diff --git a/hyracks/hyracks-storage-am-lsm-btree/src/main/java/org/apache/hyracks/storage/am/lsm/btree/dataflow/ExternalBTreeDataflowHelper.java b/hyracks/hyracks-storage-am-lsm-btree/src/main/java/org/apache/hyracks/storage/am/lsm/btree/dataflow/ExternalBTreeDataflowHelper.java
index 44d81ab..c82bf28 100644
--- a/hyracks/hyracks-storage-am-lsm-btree/src/main/java/org/apache/hyracks/storage/am/lsm/btree/dataflow/ExternalBTreeDataflowHelper.java
+++ b/hyracks/hyracks-storage-am-lsm-btree/src/main/java/org/apache/hyracks/storage/am/lsm/btree/dataflow/ExternalBTreeDataflowHelper.java
@@ -56,13 +56,16 @@
 
     @Override
     public IIndex getIndexInstance() {
-        if (index != null)
+        if (index != null) {
             return index;
+        }
         synchronized (lcManager) {
-            try {
-                index = lcManager.getIndex(resourcePath);
-            } catch (HyracksDataException e) {
-                return null;
+            if (index == null) {
+                try {
+                    index = lcManager.getIndex(resourcePath);
+                } catch (HyracksDataException e) {
+                    return null;
+                }
             }
         }
         return index;
diff --git a/hyracks/hyracks-storage-am-lsm-btree/src/main/java/org/apache/hyracks/storage/am/lsm/btree/dataflow/ExternalBTreeWithBuddyDataflowHelper.java b/hyracks/hyracks-storage-am-lsm-btree/src/main/java/org/apache/hyracks/storage/am/lsm/btree/dataflow/ExternalBTreeWithBuddyDataflowHelper.java
index 81beadd..56e9014 100644
--- a/hyracks/hyracks-storage-am-lsm-btree/src/main/java/org/apache/hyracks/storage/am/lsm/btree/dataflow/ExternalBTreeWithBuddyDataflowHelper.java
+++ b/hyracks/hyracks-storage-am-lsm-btree/src/main/java/org/apache/hyracks/storage/am/lsm/btree/dataflow/ExternalBTreeWithBuddyDataflowHelper.java
@@ -57,13 +57,16 @@
 
     @Override
     public IIndex getIndexInstance() {
-        if (index != null)
+        if (index != null) {
             return index;
+        }
         synchronized (lcManager) {
-            try {
-                index = lcManager.getIndex(resourcePath);
-            } catch (HyracksDataException e) {
-                return null;
+            if (index == null) {
+                try {
+                    index = lcManager.getIndex(resourcePath);
+                } catch (HyracksDataException e) {
+                    return null;
+                }
             }
         }
         return index;
diff --git a/hyracks/hyracks-storage-am-lsm-common/src/main/java/org/apache/hyracks/storage/am/lsm/common/impls/VirtualBufferCache.java b/hyracks/hyracks-storage-am-lsm-common/src/main/java/org/apache/hyracks/storage/am/lsm/common/impls/VirtualBufferCache.java
index 272f970..6b8cf35 100644
--- a/hyracks/hyracks-storage-am-lsm-common/src/main/java/org/apache/hyracks/storage/am/lsm/common/impls/VirtualBufferCache.java
+++ b/hyracks/hyracks-storage-am-lsm-common/src/main/java/org/apache/hyracks/storage/am/lsm/common/impls/VirtualBufferCache.java
@@ -96,7 +96,7 @@
         }
 
         for (int i = 0; i < buckets.length; i++) {
-            CacheBucket bucket = buckets[i];
+            final CacheBucket bucket = buckets[i];
             bucket.bucketLock.lock();
             try {
                 VirtualPage prev = null;
diff --git a/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/org/apache/hyracks/storage/am/lsm/invertedindex/inmemory/PartitionedInMemoryInvertedIndex.java b/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/org/apache/hyracks/storage/am/lsm/invertedindex/inmemory/PartitionedInMemoryInvertedIndex.java
index 273aa16..39dcd4a 100644
--- a/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/org/apache/hyracks/storage/am/lsm/invertedindex/inmemory/PartitionedInMemoryInvertedIndex.java
+++ b/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/org/apache/hyracks/storage/am/lsm/invertedindex/inmemory/PartitionedInMemoryInvertedIndex.java
@@ -72,13 +72,16 @@
 
     public void updatePartitionIndexes(short numTokens) {
         partitionIndexLock.writeLock().lock();
-        if (numTokens < minPartitionIndex) {
-            minPartitionIndex = numTokens;
+        try {
+            if (numTokens < minPartitionIndex) {
+                minPartitionIndex = numTokens;
+            }
+            if (numTokens > maxPartitionIndex) {
+                maxPartitionIndex = numTokens;
+            }
+        } finally {
+            partitionIndexLock.writeLock().unlock();
         }
-        if (numTokens > maxPartitionIndex) {
-            maxPartitionIndex = numTokens;
-        }
-        partitionIndexLock.writeLock().unlock();
     }
 
     @Override
diff --git a/hyracks/hyracks-storage-am-lsm-rtree/src/main/java/org/apache/hyracks/storage/am/lsm/rtree/dataflow/ExternalRTreeDataflowHelper.java b/hyracks/hyracks-storage-am-lsm-rtree/src/main/java/org/apache/hyracks/storage/am/lsm/rtree/dataflow/ExternalRTreeDataflowHelper.java
index 6f1c34a..48cc476 100644
--- a/hyracks/hyracks-storage-am-lsm-rtree/src/main/java/org/apache/hyracks/storage/am/lsm/rtree/dataflow/ExternalRTreeDataflowHelper.java
+++ b/hyracks/hyracks-storage-am-lsm-rtree/src/main/java/org/apache/hyracks/storage/am/lsm/rtree/dataflow/ExternalRTreeDataflowHelper.java
@@ -72,13 +72,16 @@
 
     @Override
     public IIndex getIndexInstance() {
-        if (index != null)
+        if (index != null) {
             return index;
+        }
         synchronized (lcManager) {
-            try {
-                index = lcManager.getIndex(resourcePath);
-            } catch (HyracksDataException e) {
-                return null;
+            if (index == null) {
+                try {
+                    index = lcManager.getIndex(resourcePath);
+                } catch (HyracksDataException e) {
+                    return null;
+                }
             }
         }
         return index;
diff --git a/hyracks/hyracks-storage-am-lsm-rtree/src/main/java/org/apache/hyracks/storage/am/lsm/rtree/impls/LSMRTreeAbstractCursor.java b/hyracks/hyracks-storage-am-lsm-rtree/src/main/java/org/apache/hyracks/storage/am/lsm/rtree/impls/LSMRTreeAbstractCursor.java
index d5257fe..c8f05c2 100644
--- a/hyracks/hyracks-storage-am-lsm-rtree/src/main/java/org/apache/hyracks/storage/am/lsm/rtree/impls/LSMRTreeAbstractCursor.java
+++ b/hyracks/hyracks-storage-am-lsm-rtree/src/main/java/org/apache/hyracks/storage/am/lsm/rtree/impls/LSMRTreeAbstractCursor.java
@@ -67,7 +67,7 @@
 
     public LSMRTreeAbstractCursor(ILSMIndexOperationContext opCtx) {
         this.opCtx = opCtx;
-        btreeRangePredicate = new RangePredicate(null, null, true, true, btreeCmp, btreeCmp);
+        btreeRangePredicate = new RangePredicate(null, null, true, true, null, null);
     }
 
     public RTreeSearchCursor getCursor(int cursorIndex) {
diff --git a/hyracks/hyracks-storage-am-rtree/src/main/java/org/apache/hyracks/storage/am/rtree/linearize/ZCurveIntComparator.java b/hyracks/hyracks-storage-am-rtree/src/main/java/org/apache/hyracks/storage/am/rtree/linearize/ZCurveIntComparator.java
index f62ae27..2f372e2 100644
--- a/hyracks/hyracks-storage-am-rtree/src/main/java/org/apache/hyracks/storage/am/rtree/linearize/ZCurveIntComparator.java
+++ b/hyracks/hyracks-storage-am-rtree/src/main/java/org/apache/hyracks/storage/am/rtree/linearize/ZCurveIntComparator.java
@@ -21,7 +21,6 @@
 import org.apache.hyracks.api.dataflow.value.ILinearizeComparator;
 import org.apache.hyracks.data.std.primitive.DoublePointable;
 import org.apache.hyracks.data.std.primitive.IntegerPointable;
-import org.apache.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
 import org.apache.hyracks.storage.am.common.ophelpers.DoubleArrayList;
 
 /*
@@ -48,7 +47,7 @@
     }
 
     private void resetStateMachine() {
-        stepsize = Integer.MAX_VALUE / 2;
+        stepsize = Integer.MAX_VALUE / 2.0f;
         bounds = new double[dim];
         boundsStack.clear();
     }
diff --git a/hyracks/hyracks-storage-common/src/main/java/org/apache/hyracks/storage/common/buffercache/BufferCache.java b/hyracks/hyracks-storage-common/src/main/java/org/apache/hyracks/storage/common/buffercache/BufferCache.java
index 75adfc9..27d0423 100644
--- a/hyracks/hyracks-storage-common/src/main/java/org/apache/hyracks/storage/common/buffercache/BufferCache.java
+++ b/hyracks/hyracks-storage-common/src/main/java/org/apache/hyracks/storage/common/buffercache/BufferCache.java
@@ -448,7 +448,7 @@
         buffer.append("cpid -> [fileId:pageId, pinCount, valid/invalid, confiscated/physical, dirty/clean]");
         int nCachedPages = 0;
         for (int i = 0; i < pageMap.length; ++i) {
-            CacheBucket cb = pageMap[i];
+            final CacheBucket cb = pageMap[i];
             cb.bucketLock.lock();
             try {
                 CachedPage cp = cb.cachedPage;
@@ -786,7 +786,7 @@
 
     private void sweepAndFlush(int fileId, boolean flushDirtyPages) throws HyracksDataException {
         for (int i = 0; i < pageMap.length; ++i) {
-            CacheBucket bucket = pageMap[i];
+            final CacheBucket bucket = pageMap[i];
             bucket.bucketLock.lock();
             try {
                 CachedPage prev = bucket.cachedPage;
diff --git a/hyracks/hyracks-dataflow-std/src/main/java/org/apache/hyracks/dataflow/std/util/MathUtil.java b/hyracks/hyracks-util/src/main/java/org/apache/hyracks/util/MathUtil.java
similarity index 92%
rename from hyracks/hyracks-dataflow-std/src/main/java/org/apache/hyracks/dataflow/std/util/MathUtil.java
rename to hyracks/hyracks-util/src/main/java/org/apache/hyracks/util/MathUtil.java
index ebdeeefc..2b157e4 100644
--- a/hyracks/hyracks-dataflow-std/src/main/java/org/apache/hyracks/dataflow/std/util/MathUtil.java
+++ b/hyracks/hyracks-util/src/main/java/org/apache/hyracks/util/MathUtil.java
@@ -17,7 +17,7 @@
  * under the License.
  */
 
-package org.apache.hyracks.dataflow.std.util;
+package org.apache.hyracks.util;
 
 public class MathUtil {
     /**
@@ -51,4 +51,8 @@
 
         return log + (n >>> 1);
     }
+
+    public static int stripSignBit(int n) {
+        return n & 0x7fffffff;
+    }
 }
diff --git a/hyracks/hyracks-dataflow-std/src/test/java/org/apache/hyracks/dataflow/std/util/MathTest.java b/hyracks/hyracks-util/src/test/java/org/apache/hyracks/util/MathTest.java
similarity index 96%
rename from hyracks/hyracks-dataflow-std/src/test/java/org/apache/hyracks/dataflow/std/util/MathTest.java
rename to hyracks/hyracks-util/src/test/java/org/apache/hyracks/util/MathTest.java
index 3c8af9f..c3443c8 100644
--- a/hyracks/hyracks-dataflow-std/src/test/java/org/apache/hyracks/dataflow/std/util/MathTest.java
+++ b/hyracks/hyracks-util/src/test/java/org/apache/hyracks/util/MathTest.java
@@ -17,14 +17,14 @@
  * under the License.
  */
 
-package org.apache.hyracks.dataflow.std.util;
-
-import static org.junit.Assert.assertTrue;
+package org.apache.hyracks.util;
 
 import java.util.Random;
 
 import org.junit.Test;
 
+import static org.junit.Assert.assertTrue;
+
 public class MathTest {
 
     @Test