diff --git a/hyracks/hyracks-control/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/partitions/MaterializingPipelinedPartition.java b/hyracks/hyracks-control/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/partitions/MaterializingPipelinedPartition.java
index 7c16be0..e292a34 100644
--- a/hyracks/hyracks-control/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/partitions/MaterializingPipelinedPartition.java
+++ b/hyracks/hyracks-control/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/partitions/MaterializingPipelinedPartition.java
@@ -139,7 +139,7 @@
         if (LOGGER.isLoggable(Level.INFO)) {
             LOGGER.info("open(" + pid + " by " + taId);
         }
-        fRef = manager.getFileFactory().createUnmanagedWorkspaceFile(pid.toString().replace(':', '_'));
+        fRef = manager.getFileFactory().createUnmanagedWorkspaceFile(pid.toString());
         handle = ctx.getIOManager().open(fRef, IIOManager.FileReadWriteMode.READ_WRITE,
                 IIOManager.FileSyncMode.METADATA_ASYNC_DATA_ASYNC);
         size = 0;
@@ -177,4 +177,4 @@
             manager.updatePartitionState(pid, taId, this, PartitionState.COMMITTED);
         }
     }
-}
\ No newline at end of file
+}
diff --git a/hyracks/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/preclustered/PreclusteredGroupWriter.java b/hyracks/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/preclustered/PreclusteredGroupWriter.java
index 4ae43eb..002aa3b 100644
--- a/hyracks/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/preclustered/PreclusteredGroupWriter.java
+++ b/hyracks/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/preclustered/PreclusteredGroupWriter.java
@@ -29,26 +29,20 @@
 import edu.uci.ics.hyracks.dataflow.std.group.IAggregatorDescriptor;
 
 public class PreclusteredGroupWriter implements IFrameWriter {
-
-    private final static int INT_SIZE = 4;
-
     private final int[] groupFields;
     private final IBinaryComparator[] comparators;
     private final IAggregatorDescriptor aggregator;
     private final AggregateState aggregateState;
     private final IFrameWriter writer;
+    private final ByteBuffer copyFrame;
     private final FrameTupleAccessor inFrameAccessor;
+    private final FrameTupleAccessor copyFrameAccessor;
 
     private final ByteBuffer outFrame;
     private final FrameTupleAppender appender;
     private final ArrayTupleBuilder tupleBuilder;
 
-    private final RecordDescriptor outRecordDesc;
-
-    private byte[] groupResultCache;
-    private ByteBuffer groupResultCacheBuffer;
-    private FrameTupleAccessor groupResultCacheAccessor;
-    private FrameTupleAppender groupResultCacheAppender;
+    private boolean first;
 
     public PreclusteredGroupWriter(IHyracksTaskContext ctx, int[] groupFields, IBinaryComparator[] comparators,
             IAggregatorDescriptor aggregator, RecordDescriptor inRecordDesc, RecordDescriptor outRecordDesc,
@@ -58,9 +52,10 @@
         this.aggregator = aggregator;
         this.aggregateState = aggregator.createAggregateStates();
         this.writer = writer;
-        this.outRecordDesc = outRecordDesc;
-
+        copyFrame = ctx.allocateFrame();
         inFrameAccessor = new FrameTupleAccessor(ctx.getFrameSize(), inRecordDesc);
+        copyFrameAccessor = new FrameTupleAccessor(ctx.getFrameSize(), inRecordDesc);
+        copyFrameAccessor.reset(copyFrame);
 
         outFrame = ctx.allocateFrame();
         appender = new FrameTupleAppender(ctx.getFrameSize());
@@ -72,6 +67,7 @@
     @Override
     public void open() throws HyracksDataException {
         writer.open();
+        first = true;
     }
 
     @Override
@@ -79,45 +75,40 @@
         inFrameAccessor.reset(buffer);
         int nTuples = inFrameAccessor.getTupleCount();
         for (int i = 0; i < nTuples; ++i) {
+            if (first) {
 
-            if (groupResultCache != null && groupResultCacheAccessor.getTupleCount() > 0) {
-                groupResultCacheAccessor.reset(ByteBuffer.wrap(groupResultCache));
-                if (sameGroup(inFrameAccessor, i, groupResultCacheAccessor, 0)) {
-                    // find match: do aggregation
-                    aggregator.aggregate(inFrameAccessor, i, groupResultCacheAccessor, 0, aggregateState);
-                    continue;
-                } else {
-                    // write the cached group into the final output
-                    writeOutput(groupResultCacheAccessor, 0);
+                tupleBuilder.reset();
+                for (int j = 0; j < groupFields.length; j++) {
+                    tupleBuilder.addField(inFrameAccessor, i, groupFields[j]);
                 }
+                aggregator.init(tupleBuilder, inFrameAccessor, i, aggregateState);
+
+                first = false;
+
+            } else {
+                if (i == 0) {
+                    switchGroupIfRequired(copyFrameAccessor, copyFrameAccessor.getTupleCount() - 1, inFrameAccessor, i);
+                } else {
+                    switchGroupIfRequired(inFrameAccessor, i - 1, inFrameAccessor, i);
+                }
+
             }
+        }
+        FrameUtils.copy(buffer, copyFrame);
+    }
+
+    private void switchGroupIfRequired(FrameTupleAccessor prevTupleAccessor, int prevTupleIndex,
+            FrameTupleAccessor currTupleAccessor, int currTupleIndex) throws HyracksDataException {
+        if (!sameGroup(prevTupleAccessor, prevTupleIndex, currTupleAccessor, currTupleIndex)) {
+            writeOutput(prevTupleAccessor, prevTupleIndex);
 
             tupleBuilder.reset();
-
             for (int j = 0; j < groupFields.length; j++) {
-                tupleBuilder.addField(inFrameAccessor, i, groupFields[j]);
+                tupleBuilder.addField(currTupleAccessor, currTupleIndex, groupFields[j]);
             }
-
-            aggregator.init(tupleBuilder, inFrameAccessor, i, aggregateState);
-
-            // enlarge the cache buffer if necessary
-            int requiredSize = tupleBuilder.getSize() + tupleBuilder.getFieldEndOffsets().length * INT_SIZE + 2
-                    * INT_SIZE;
-
-            if (groupResultCache == null || groupResultCache.length < requiredSize) {
-                groupResultCache = new byte[requiredSize];
-                groupResultCacheAppender = new FrameTupleAppender(groupResultCache.length);
-                groupResultCacheBuffer = ByteBuffer.wrap(groupResultCache);
-                groupResultCacheAccessor = new FrameTupleAccessor(groupResultCache.length, outRecordDesc);
-            }
-
-            groupResultCacheAppender.reset(groupResultCacheBuffer, true);
-            if (!groupResultCacheAppender.append(tupleBuilder.getFieldEndOffsets(), tupleBuilder.getByteArray(), 0,
-                    tupleBuilder.getSize())) {
-                throw new HyracksDataException("The partial result is too large to be initialized in a frame.");
-            }
-            
-            groupResultCacheAccessor.reset(groupResultCacheBuffer);
+            aggregator.init(tupleBuilder, currTupleAccessor, currTupleIndex, aggregateState);
+        } else {
+            aggregator.aggregate(currTupleAccessor, currTupleIndex, null, 0, aggregateState);
         }
     }
 
@@ -126,7 +117,7 @@
 
         tupleBuilder.reset();
         for (int j = 0; j < groupFields.length; j++) {
-            tupleBuilder.addField(lastTupleAccessor, lastTupleIndex, j);
+            tupleBuilder.addField(lastTupleAccessor, lastTupleIndex, groupFields[j]);
         }
         aggregator.outputFinalResult(tupleBuilder, lastTupleAccessor, lastTupleIndex, aggregateState);
 
@@ -147,8 +138,8 @@
             int fIdx = groupFields[i];
             int s1 = a1.getTupleStartOffset(t1Idx) + a1.getFieldSlotsLength() + a1.getFieldStartOffset(t1Idx, fIdx);
             int l1 = a1.getFieldLength(t1Idx, fIdx);
-            int s2 = a2.getTupleStartOffset(t2Idx) + a2.getFieldSlotsLength() + a2.getFieldStartOffset(t2Idx, i);
-            int l2 = a2.getFieldLength(t2Idx, i);
+            int s2 = a2.getTupleStartOffset(t2Idx) + a2.getFieldSlotsLength() + a2.getFieldStartOffset(t2Idx, fIdx);
+            int l2 = a2.getFieldLength(t2Idx, fIdx);
             if (comparators[i].compare(a1.getBuffer().array(), s1, l1, a2.getBuffer().array(), s2, l2) != 0) {
                 return false;
             }
@@ -163,8 +154,8 @@
 
     @Override
     public void close() throws HyracksDataException {
-        if (groupResultCache != null && groupResultCacheAccessor.getTupleCount() > 0) {
-            writeOutput(groupResultCacheAccessor, 0);
+        if (!first) {
+            writeOutput(copyFrameAccessor, copyFrameAccessor.getTupleCount() - 1);
             if (appender.getTupleCount() > 0) {
                 FrameUtils.flushFrame(outFrame, writer);
             }
@@ -172,4 +163,4 @@
         aggregateState.close();
         writer.close();
     }
-}
\ No newline at end of file
+}
diff --git a/hyracks/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/misc/PrinterOperatorDescriptor.java b/hyracks/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/misc/PrinterOperatorDescriptor.java
index 088c5ee..4f9f6ec 100644
--- a/hyracks/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/misc/PrinterOperatorDescriptor.java
+++ b/hyracks/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/misc/PrinterOperatorDescriptor.java
@@ -48,10 +48,10 @@
         @Override
         public void writeData(Object[] data) throws HyracksDataException {
             for (int i = 0; i < data.length; ++i) {
-            //    System.err.print(StringSerializationUtils.toString(data[i]));
-            //    System.err.print(", ");
+                System.err.print(StringSerializationUtils.toString(data[i]));
+                System.err.print(", ");
             }
-            //System.err.println();
+            System.err.println();
         }
 
         @Override
@@ -66,4 +66,4 @@
         return new DeserializedOperatorNodePushable(ctx, new PrinterOperator(),
                 recordDescProvider.getInputRecordDescriptor(getActivityId(), 0));
     }
-}
\ No newline at end of file
+}
diff --git a/hyracks/hyracks-examples/hadoop-compat-example/hadoopcompatserver/pom.xml b/hyracks/hyracks-examples/hadoop-compat-example/hadoopcompatserver/pom.xml
index d166e45..ba30424 100644
--- a/hyracks/hyracks-examples/hadoop-compat-example/hadoopcompatserver/pom.xml
+++ b/hyracks/hyracks-examples/hadoop-compat-example/hadoopcompatserver/pom.xml
@@ -125,9 +125,8 @@
       	<artifactId>maven-compiler-plugin</artifactId>
       	<version>2.0.2</version>
         <configuration>
-          <source>1.7</source>
-          <target>1.7</target>
-          <fork>true</fork>
+          <source>1.6</source>
+          <target>1.6</target>
         </configuration>
       </plugin>
       <plugin>
diff --git a/hyracks/hyracks-examples/text-example/textserver/pom.xml b/hyracks/hyracks-examples/text-example/textserver/pom.xml
index f67d444..b12f823 100644
--- a/hyracks/hyracks-examples/text-example/textserver/pom.xml
+++ b/hyracks/hyracks-examples/text-example/textserver/pom.xml
@@ -124,9 +124,8 @@
       	<artifactId>maven-compiler-plugin</artifactId>
       	<version>2.0.2</version>
         <configuration>
-          <source>1.7</source>
-          <target>1.7</target>
-          <fork>true</fork>
+          <source>1.6</source>
+          <target>1.6</target>
         </configuration>
       </plugin>
       <plugin>
diff --git a/hyracks/hyracks-hdfs/hyracks-hdfs-core/pom.xml b/hyracks/hyracks-hdfs/hyracks-hdfs-core/pom.xml
index e97f26f..032d50d 100644
--- a/hyracks/hyracks-hdfs/hyracks-hdfs-core/pom.xml
+++ b/hyracks/hyracks-hdfs/hyracks-hdfs-core/pom.xml
@@ -66,18 +66,6 @@
 					</filesets>
 				</configuration>
 			</plugin>
-			<plugin>
-				<groupId>org.apache.maven.plugins</groupId>
-				<artifactId>maven-jar-plugin</artifactId>
-				<version>2.2</version>
-				<executions>
-					<execution>
-						<goals>
-							<goal>test-jar</goal>
-						</goals>
-					</execution>
-				</executions>
-			</plugin>
 		</plugins>
 	</build>
 
diff --git a/pregelix/pregelix-core/src/main/java/edu/uci/ics/pregelix/core/driver/Driver.java b/pregelix/pregelix-core/src/main/java/edu/uci/ics/pregelix/core/driver/Driver.java
index 300dce4..2d4064b 100644
--- a/pregelix/pregelix-core/src/main/java/edu/uci/ics/pregelix/core/driver/Driver.java
+++ b/pregelix/pregelix-core/src/main/java/edu/uci/ics/pregelix/core/driver/Driver.java
@@ -136,7 +136,6 @@
                 terminate = IterationUtils.readTerminationState(job.getConfiguration(), jobGen.getJobId())
                         || IterationUtils.readForceTerminationState(job.getConfiguration(), jobGen.getJobId());
                 i++;
-                
             } while (!terminate);
 
             start = System.currentTimeMillis();
diff --git a/pregelix/pregelix-core/src/test/java/edu/uci/ics/pregelix/core/join/JoinTest.java b/pregelix/pregelix-core/src/test/java/edu/uci/ics/pregelix/core/join/JoinTest.java
index e8ab2ed..4c7f91d 100644
--- a/pregelix/pregelix-core/src/test/java/edu/uci/ics/pregelix/core/join/JoinTest.java
+++ b/pregelix/pregelix-core/src/test/java/edu/uci/ics/pregelix/core/join/JoinTest.java
@@ -102,7 +102,7 @@
         ClusterConfig.setStorePath(PATH_TO_CLUSTER_STORE);
         ClusterConfig.setClusterPropertiesPath(PATH_TO_CLUSTER_PROPERTIES);
         cleanupStores();
-        PregelixHyracksIntegrationUtil.init("src/test/resources/topology.xml");
+        PregelixHyracksIntegrationUtil.init();
 
         FileUtils.forceMkdir(new File(EXPECT_RESULT_DIR));
         FileUtils.forceMkdir(new File(ACTUAL_RESULT_DIR));
diff --git a/pregelix/pregelix-example/src/test/java/edu/uci/ics/pregelix/example/dataload/DataLoadTest.java b/pregelix/pregelix-example/src/test/java/edu/uci/ics/pregelix/example/dataload/DataLoadTest.java
index 91aa0d7..b4e17b6 100644
--- a/pregelix/pregelix-example/src/test/java/edu/uci/ics/pregelix/example/dataload/DataLoadTest.java
+++ b/pregelix/pregelix-example/src/test/java/edu/uci/ics/pregelix/example/dataload/DataLoadTest.java
@@ -76,7 +76,7 @@
         ClusterConfig.setStorePath(PATH_TO_CLUSTER_STORE);
         ClusterConfig.setClusterPropertiesPath(PATH_TO_CLUSTER_PROPERTIES);
         cleanupStores();
-        PregelixHyracksIntegrationUtil.init("src/test/resources/topology.xml");
+        PregelixHyracksIntegrationUtil.init();
         LOGGER.info("Hyracks mini-cluster started");
         startHDFS();
         FileUtils.forceMkdir(new File(EXPECT_RESULT_DIR));
diff --git a/pregelix/pregelix-example/src/test/java/edu/uci/ics/pregelix/example/jobrun/RunJobTestSuite.java b/pregelix/pregelix-example/src/test/java/edu/uci/ics/pregelix/example/jobrun/RunJobTestSuite.java
index 7757f86..ea89bb9 100644
--- a/pregelix/pregelix-example/src/test/java/edu/uci/ics/pregelix/example/jobrun/RunJobTestSuite.java
+++ b/pregelix/pregelix-example/src/test/java/edu/uci/ics/pregelix/example/jobrun/RunJobTestSuite.java
@@ -77,7 +77,7 @@
         ClusterConfig.setStorePath(PATH_TO_CLUSTER_STORE);
         ClusterConfig.setClusterPropertiesPath(PATH_TO_CLUSTER_PROPERTIES);
         cleanupStores();
-        PregelixHyracksIntegrationUtil.init("src/test/resources/topology.xml");
+        PregelixHyracksIntegrationUtil.init();
         LOGGER.info("Hyracks mini-cluster started");
         FileUtils.forceMkdir(new File(ACTUAL_RESULT_DIR));
         FileUtils.cleanDirectory(new File(ACTUAL_RESULT_DIR));