diff --git src/java/org/apache/hadoop/mapred/TaskTracker.java src/java/org/apache/hadoop/mapred/TaskTracker.java
index 61a11ef..55a4c3d 100644
--- src/java/org/apache/hadoop/mapred/TaskTracker.java
+++ src/java/org/apache/hadoop/mapred/TaskTracker.java
@@ -1669,7 +1669,7 @@ public class TaskTracker
       if (localDirsDf.containsKey(localDirs[i])) {
         df = localDirsDf.get(localDirs[i]);
       } else {
-        df = new DF(new File(localDirs[i]), fConf);
+        df = DF.getDF(new File(localDirs[i]), fConf);
         localDirsDf.put(localDirs[i], df);
       }