diff --git a/hadoop-mapreduce-project/CHANGES.txt b/hadoop-mapreduce-project/CHANGES.txt
index 37ccdda2c0e..a54ba67f187 100644
--- a/hadoop-mapreduce-project/CHANGES.txt
+++ b/hadoop-mapreduce-project/CHANGES.txt
@@ -696,6 +696,9 @@ Release 0.23.7 - UNRELEASED
     MAPREDUCE-4946. Fix a performance problem for large jobs by reducing the
     number of map completion event type conversions. (Jason Lowe via sseth)
 
+    MAPREDUCE-4822. Unnecessary conversions in History Events. (Chu Tong via
+    jlowe)
+
   BUG FIXES
 
     MAPREDUCE-4458. Warn if java.library.path is used for AM or Task
diff --git a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/MapAttemptFinishedEvent.java b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/MapAttemptFinishedEvent.java
index d4f9fa316b9..62df2aae929 100644
--- a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/MapAttemptFinishedEvent.java
+++ b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/MapAttemptFinishedEvent.java
@@ -178,7 +178,7 @@ public TaskAttemptID getAttemptId() {
 
   /** Get the task type */
   public TaskType getTaskType() {
-    return TaskType.valueOf(taskType.toString());
+    return taskType;
   }
   /** Get the task status */
   public String getTaskStatus() { return taskStatus.toString(); }
diff --git a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/ReduceAttemptFinishedEvent.java b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/ReduceAttemptFinishedEvent.java
index 10b8c1f0139..a779fca6ec8 100644
--- a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/ReduceAttemptFinishedEvent.java
+++ b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/ReduceAttemptFinishedEvent.java
@@ -176,11 +176,11 @@ public void setDatum(Object oDatum) {
   public TaskID getTaskId() { return attemptId.getTaskID(); }
   /** Get the attempt id */
   public TaskAttemptID getAttemptId() {
-    return TaskAttemptID.forName(attemptId.toString());
+    return attemptId;
   }
   /** Get the task type */
   public TaskType getTaskType() {
-    return TaskType.valueOf(taskType.toString());
+    return taskType;
   }
   /** Get the task status */
   public String getTaskStatus() { return taskStatus.toString(); }
diff --git a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/TaskAttemptFinishedEvent.java b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/TaskAttemptFinishedEvent.java
index a62ca38e4a8..78b9ca914f6 100644
--- a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/TaskAttemptFinishedEvent.java
+++ b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/TaskAttemptFinishedEvent.java
@@ -105,11 +105,11 @@ public void setDatum(Object oDatum) {
   public TaskID getTaskId() { return attemptId.getTaskID(); }
   /** Get the task attempt id */
   public TaskAttemptID getAttemptId() {
-    return TaskAttemptID.forName(attemptId.toString());
+    return attemptId;
   }
   /** Get the task type */
   public TaskType getTaskType() {
-    return TaskType.valueOf(taskType.toString());
+    return taskType;
   }
   /** Get the task status */
   public String getTaskStatus() { return taskStatus.toString(); }
diff --git a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/TaskFinishedEvent.java b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/TaskFinishedEvent.java
index 55de80ca63f..edbf0099ff9 100644
--- a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/TaskFinishedEvent.java
+++ b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/jobhistory/TaskFinishedEvent.java
@@ -95,14 +95,10 @@ public void setDatum(Object oDatum) {
   }
 
   /** Get task id */
-  public TaskID getTaskId() { return TaskID.forName(taskid.toString()); }
+  public TaskID getTaskId() { return taskid; }
   /** Get successful task attempt id */
   public TaskAttemptID getSuccessfulTaskAttemptId() {
-    if(successfulAttemptId != null)
-    {
-      return TaskAttemptID.forName(successfulAttemptId.toString());
-    }
-    return null;
+    return successfulAttemptId;
   }
   /** Get the task finish time */
   public long getFinishTime() { return finishTime; }
@@ -110,7 +106,7 @@ public TaskAttemptID getSuccessfulTaskAttemptId() {
   public Counters getCounters() { return counters; }
   /** Get task type */
   public TaskType getTaskType() {
-    return TaskType.valueOf(taskType.toString());
+    return taskType;
   }
   /** Get task status */
   public String getTaskStatus() { return status.toString(); }