verify duplicate keys in bulkload
diff --git a/pregelix/pregelix-core/src/main/java/edu/uci/ics/pregelix/core/jobgen/JobGen.java b/pregelix/pregelix-core/src/main/java/edu/uci/ics/pregelix/core/jobgen/JobGen.java
index 478ac07..42359eb 100644
--- a/pregelix/pregelix-core/src/main/java/edu/uci/ics/pregelix/core/jobgen/JobGen.java
+++ b/pregelix/pregelix-core/src/main/java/edu/uci/ics/pregelix/core/jobgen/JobGen.java
@@ -241,7 +241,7 @@
         typeTraits[1] = new TypeTraits(false);
         TreeIndexBulkLoadOperatorDescriptor btreeBulkLoad = new TreeIndexBulkLoadOperatorDescriptor(spec,
                 storageManagerInterface, lcManagerProvider, fileSplitProvider, typeTraits, comparatorFactories,
-                sortFields, fieldPermutation, DEFAULT_BTREE_FILL_FACTOR, false, 0, false,
+                sortFields, fieldPermutation, DEFAULT_BTREE_FILL_FACTOR, true, 0, false,
                 getIndexDataflowHelperFactory(), NoOpOperationCallbackFactory.INSTANCE);
         ClusterConfig.setLocationConstraint(spec, btreeBulkLoad);