MAPREDUCE-6363. [NNBench] Lease mismatch error when running with multiple mappers. Contributed by Brahma Reddy Battula.

hadoop-mapreduce-project/CHANGES.txt

@@ -471,6 +471,9 @@ Release 2.8.0 - UNRELEASED
     MAPREDUCE-6389. Fix BaileyBorweinPlouffe CLI usage message. (Brahma Reddy Battula
     via devaraj)
 
+    MAPREDUCE-6363. [NNBench] Lease mismatch error when running with multiple
+    mappers. (Brahma Reddy Battula via aajisaka)
+
 Release 2.7.1 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-jobclient/src/test/java/org/apache/hadoop/hdfs/NNBench.java

@@ -57,6 +57,9 @@ import org.apache.hadoop.mapred.Reporter;
 import org.apache.hadoop.mapred.OutputCollector;
 import org.apache.hadoop.mapred.JobConf;
 import org.apache.hadoop.mapred.Reducer;
+import org.apache.hadoop.mapreduce.MRJobConfig;
+import org.apache.hadoop.mapreduce.TaskAttemptID;
+import org.apache.hadoop.mapreduce.v2.api.records.TaskId;
 
 /**
  * This program executes a specified operation that applies load to 
@@ -687,6 +690,9 @@ public class NNBench {
       dataDirName = conf.get("test.nnbench.datadir.name");
       op = conf.get("test.nnbench.operation");
       readFile = conf.getBoolean("test.nnbench.readFileAfterOpen", false);
+      int taskId =
+          TaskAttemptID.forName(conf.get(MRJobConfig.TASK_ATTEMPT_ID))
+              .getTaskID().getId();
       
       long totalTimeTPmS = 0l;
       long startTimeTPmS = 0l;
@@ -699,18 +705,19 @@ public class NNBench {
       successfulFileOps = 0l;
       
       if (barrier()) {
+        String filePrefix = "file_" + taskId + "_";
         if (op.equals(OP_CREATE_WRITE)) {
           startTimeTPmS = System.currentTimeMillis();
-          doCreateWriteOp("file_" + hostName + "_", reporter);
+          doCreateWriteOp(filePrefix, reporter);
         } else if (op.equals(OP_OPEN_READ)) {
           startTimeTPmS = System.currentTimeMillis();
-          doOpenReadOp("file_" + hostName + "_", reporter);
+          doOpenReadOp(filePrefix, reporter);
         } else if (op.equals(OP_RENAME)) {
           startTimeTPmS = System.currentTimeMillis();
-          doRenameOp("file_" + hostName + "_", reporter);
+          doRenameOp(filePrefix, reporter);
         } else if (op.equals(OP_DELETE)) {
           startTimeTPmS = System.currentTimeMillis();
-          doDeleteOp("file_" + hostName + "_", reporter);
+          doDeleteOp(filePrefix, reporter);
         }
         
         endTimeTPms = System.currentTimeMillis();