HADOOP-4173. fix failures in TestProcfsBasedProcessTree and

TestTaskTrackerMemoryManager tests. ProcfsBasedProcessTree and
memory management in TaskTracker are disabled on Windows.
(Vinod K V via rangadi)


git-svn-id: https://svn.apache.org/repos/asf/hadoop/core/trunk@699444 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -768,6 +768,11 @@ Release 0.19.0 - Unreleased
     HADOOP-4275. Move public method isJobValidName from JobID to a private
     method in JobTracker. (omalley)
 
+    HADOOP-4173. fix failures in TestProcfsBasedProcessTree and
+    TestTaskTrackerMemoryManager tests. ProcfsBasedProcessTree and
+    memory management in TaskTracker are disabled on Windows.
+    (Vinod K V via rangadi)
+
 Release 0.18.2 - Unreleased
 
   BUG FIXES

conf/hadoop-default.xml

@@ -720,7 +720,9 @@ creations/deletions), or "all".</description>
   <name>mapred.tasktracker.taskmemorymanager.monitoring-interval</name>
   <value>5000</value>
   <description>The interval, in milliseconds, for which the tasktracker waits
-   between two cycles of monitoring its tasks' memory usage.</description>
+   between two cycles of monitoring its tasks' memory usage. Used only if
+   tasks' memory management is enabled via mapred.tasktracker.tasks.maxmemory.
+   </description>
 </property>
 
 <property>
@@ -728,7 +730,8 @@ creations/deletions), or "all".</description>
   <value>5000</value>
   <description>The time, in milliseconds, the tasktracker waits for sending a
   SIGKILL to a process that has overrun memory limits, after it has been sent
-  a SIGTERM.</description>
+  a SIGTERM. Used only if tasks' memory management is enabled via
+  mapred.tasktracker.tasks.maxmemory.</description>
 </property>
 
 <property>
@@ -1468,7 +1471,9 @@ creations/deletions), or "all".</description>
   	tasks. Any task scheduled on this tasktracker is guaranteed and constrained
   	 to use a share of this amount. Any task exceeding its share will be 
   	killed. If set to -1, this functionality is disabled, and 
-  	mapred.task.maxmemory is ignored.
+  	mapred.task.maxmemory is ignored. Further, it will be enabled only on the
+  	systems where org.apache.hadoop.util.ProcfsBasedProcessTree is available,
+  	i.e at present only on Linux.
   </description>
 </property>
 

src/core/org/apache/hadoop/util/ProcfsBasedProcessTree.java

@@ -39,7 +39,7 @@ import org.apache.hadoop.util.Shell.ExitCodeException;
 import org.apache.hadoop.util.Shell.ShellCommandExecutor;
 
 /**
- * A Proc file-system based ProcfsBasedProcessTree. Works on Linux and Cygwin.
+ * A Proc file-system based ProcessTree. Works only on Linux.
  */
 public class ProcfsBasedProcessTree {
 
@@ -72,10 +72,9 @@ public class ProcfsBasedProcessTree {
   public static boolean isAvailable() {
     try {
       String osName = System.getProperty("os.name");
-      if (!osName.startsWith("Linux") && !osName.startsWith("Windows")) {
-        LOG
-            .info("ProcfsBasedProcfsBasedProcessTree currently is supported only "
-                + "on Linux and Windows");
+      if (!osName.startsWith("Linux")) {
+        LOG.info("ProcfsBasedProcessTree currently is supported only on "
+            + "Linux.");
         return false;
       }
     } catch (SecurityException se) {