diff --git a/tony-core/src/main/java/com/linkedin/tony/ApplicationMaster.java b/tony-core/src/main/java/com/linkedin/tony/ApplicationMaster.java
index b9e7dac3..498fac18 100644
--- a/tony-core/src/main/java/com/linkedin/tony/ApplicationMaster.java
+++ b/tony-core/src/main/java/com/linkedin/tony/ApplicationMaster.java
@@ -1038,21 +1038,23 @@ public void onStopContainerError(ContainerId containerId, Throwable t) {
   private class RMCallbackHandler implements AMRMClientAsync.CallbackHandler {
     @Override
     public void onContainersCompleted(List<ContainerStatus> completedContainers) {
-      LOG.info("Completed containers: " + completedContainers.size());
+      LOG.info("onContainersCompleted called in RMCallbackHandler, completed containers size: " + completedContainers.size());
       sleepForTesting();
 
       for (ContainerStatus containerStatus : completedContainers) {
         int exitStatus = containerStatus.getExitStatus();
-        LOG.info("ContainerID = " + containerStatus.getContainerId()
-            + ", state = " + containerStatus.getState()
-            + ", exitStatus = " + exitStatus);
         String diagnostics = containerStatus.getDiagnostics();
+        String outputLog = "ContainerID = " + containerStatus.getContainerId()
+                + ", state = " + containerStatus.getState()
+                + ", exitStatus = " + exitStatus
+                + ", diagnostics = " + diagnostics;
+
         String errorInformation = null;
         if (ContainerExitStatus.SUCCESS != exitStatus) {
           errorInformation = diagnostics;
-          LOG.error(diagnostics);
+          LOG.error(outputLog);
         } else {
-          LOG.info(diagnostics);
+          LOG.info(outputLog);
         }
         processFinishedContainer(containerStatus.getContainerId(), exitStatus, errorInformation);
       }
diff --git a/tony-core/src/main/java/com/linkedin/tony/TonySession.java b/tony-core/src/main/java/com/linkedin/tony/TonySession.java
index ba63f04f..a7d2dd2f 100644
--- a/tony-core/src/main/java/com/linkedin/tony/TonySession.java
+++ b/tony-core/src/main/java/com/linkedin/tony/TonySession.java
@@ -256,7 +256,9 @@ public Map<String, List<String>> getClusterSpec() {
    * Refresh task status when a TaskExecutor registers its exit code with AM.
    */
   public void onTaskCompleted(String jobName, String jobIndex, int exitCode, String taskDiagnosticMsg) {
-    LOG.info(String.format("Job %s:%s exited with %d", jobName, jobIndex, exitCode));
+    String outputLog = String.format("Job %s:%s exited with %d", jobName, jobIndex, exitCode);
+    LOG.info(outputLog);
+
     TonyTask task = getTask(jobName, jobIndex);
     Preconditions.checkNotNull(task);
     task.setExitStatus(exitCode);
@@ -271,7 +273,7 @@ public void onTaskCompleted(String jobName, String jobIndex, int exitCode, Strin
     // short circuit and immediately stop training if a worker failed.
     if (exitCode != ContainerExitStatus.SUCCESS && exitCode != ContainerExitStatus.KILLED_BY_APPMASTER) {
       if (isChief(jobName, jobIndex) || shouldStopOnFailure(jobName) || isFailOnWorkerFailure()) {
-        String diagnostic = "Exit status: " + exitCode;
+        String diagnostic = outputLog + ". Exit status: " + exitCode;
         if (taskDiagnosticMsg != null) {
           diagnostic += ". Error msg: " + taskDiagnosticMsg;
         }