diff --git a/jvm-packages/xgboost4j-spark/src/test/scala/ml/dmlc/xgboost4j/scala/spark/CommunicatorRobustnessSuite.scala b/jvm-packages/xgboost4j-spark/src/test/scala/ml/dmlc/xgboost4j/scala/spark/CommunicatorRobustnessSuite.scala
index 3b7fe4a65fea..dc2a52c4dd81 100644
--- a/jvm-packages/xgboost4j-spark/src/test/scala/ml/dmlc/xgboost4j/scala/spark/CommunicatorRobustnessSuite.scala
+++ b/jvm-packages/xgboost4j-spark/src/test/scala/ml/dmlc/xgboost4j/scala/spark/CommunicatorRobustnessSuite.scala
@@ -89,21 +89,22 @@ class CommunicatorRobustnessSuite extends AnyFunSuite with PerTest {
 
     val workerCount: Int = numWorkers
 
-    rdd.mapPartitions { iter =>
+    val dummyTasks = rdd.mapPartitions { iter =>
       val index = iter.next()
       Communicator.init(trackerEnvs)
-      val a = Array(1.0f, 2.0f, 3.0f)
-      val b = Communicator.allReduce(a, Communicator.OpType.SUM)
-      for (i <- 0 to 2) {
-        assert(a(i) * workerCount == b(i))
-      }
-      val c = Communicator.allReduce(a, Communicator.OpType.MIN);
-      for (i <- 0 to 2) {
-        assert(a(i) == c(i))
-      }
       Communicator.shutdown()
       Iterator(index)
-    }.collect()
+    }.cache()
+
+    val sparkThread = new Thread() {
+      override def run(): Unit = {
+        // forces a Spark job.
+        dummyTasks.foreachPartition(() => _)
+      }
+    }
+
+    sparkThread.setUncaughtExceptionHandler(tracker)
+    sparkThread.start()
   }
 
   test("should allow the dataframe containing communicator calls to be partially evaluated for" +