diff --git a/hyracks/hyracks-control/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/dataset/DatasetPartitionManager.java b/hyracks/hyracks-control/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/dataset/DatasetPartitionManager.java
index 688a725..9b92a22 100644
--- a/hyracks/hyracks-control/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/dataset/DatasetPartitionManager.java
+++ b/hyracks/hyracks-control/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/dataset/DatasetPartitionManager.java
@@ -82,7 +82,7 @@
         DatasetPartitionWriter dpw = null;
         JobId jobId = ctx.getJobletContext().getJobId();
         try {
-            synchronized (partitionResultStateMap) {
+            synchronized (this) {
                 ncs.getClusterController().registerResultPartitionLocation(jobId, rsId, orderedResult, partition,
                         nPartitions, ncs.getDatasetNetworkManager().getNetworkAddress());
                 dpw = new DatasetPartitionWriter(ctx, this, jobId, rsId, partition, datasetMemoryManager);
@@ -128,7 +128,7 @@
     public void initializeDatasetPartitionReader(JobId jobId, int partition, IFrameWriter writer)
             throws HyracksException {
         ResultState resultState;
-        synchronized (partitionResultStateMap) {
+        synchronized (this) {
             ResultState[] resultStates = partitionResultStateMap.get(jobId);
 
             if (resultStates == null) {