set maxRuntime in UT

diff --git a/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/execution/operator/process/AbstractConsumeAllOperator.java b/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/execution/operator/process/AbstractConsumeAllOperator.java
index c078bfb..8943d91 100644
--- a/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/execution/operator/process/AbstractConsumeAllOperator.java
+++ b/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/execution/operator/process/AbstractConsumeAllOperator.java

@@ -176,7 +176,6 @@
         child.close();
       }
     }
-    children.clear();
     // friendly for gc
     inputTsBlocks = null;
   }

diff --git a/iotdb-core/datanode/src/test/java/org/apache/iotdb/db/queryengine/execution/DataDriverTest.java b/iotdb-core/datanode/src/test/java/org/apache/iotdb/db/queryengine/execution/DataDriverTest.java
index 31fbae0..10945c3 100644
--- a/iotdb-core/datanode/src/test/java/org/apache/iotdb/db/queryengine/execution/DataDriverTest.java
+++ b/iotdb-core/datanode/src/test/java/org/apache/iotdb/db/queryengine/execution/DataDriverTest.java

@@ -164,6 +164,7 @@
                   new SingleColumnMerger(new InputLocation(0, 0), new AscTimeComparator()),
                   new SingleColumnMerger(new InputLocation(1, 0), new AscTimeComparator())),
               new AscTimeComparator());
+      timeJoinOperator.getOperatorContext().setMaxRunTime(new Duration(500, TimeUnit.MILLISECONDS));
 
       LimitOperator limitOperator =
           new LimitOperator(driverContext.getOperatorContexts().get(3), 250, timeJoinOperator);