+1 overall. Here are the results of testing the latest attachment
http://issues.apache.org/jira/secure/attachment/12596165/NNThBenchTool.patch
against trunk revision .

+1 @author. The patch does not contain any @author tags.

+1 tests included. The patch appears to include 1 new or modified test files.

+1 javac. The applied patch does not increase the total number of javac compiler warnings.

+1 javadoc. The javadoc tool did not generate any warning messages.

+1 eclipse:eclipse. The patch built with eclipse:eclipse.

+1 findbugs. The patch does not introduce any new Findbugs (version 1.3.9) warnings.

+1 release audit. The applied patch does not increase the total number of release audit warnings.

+1 core tests. The patch passed unit tests in hadoop-hdfs-project/hadoop-hdfs.

+1 contrib tests. The patch passed contrib unit tests.

Test results: https://builds.apache.org/job/PreCommit-HDFS-Build/4767//testReport/
Console output: https://builds.apache.org/job/PreCommit-HDFS-Build/4767//console

This message is automatically generated.

Hi Konstantin! Could you please point me to documentation / tell me how to actually run this tool in order to test the changes?

I usually run it using hadoop command:

hadoop org.apache.hadoop.hdfs.server.namenode.NNThroughputBenchmark

Then you will see available operations, options.
You can about background and motivation in the introductory Jira HADOOP-2149. The list of operations was subsequently extended, most of the documentation is just the JavaDoc for the class and related operations.
To test this change you can add some generic options to the hadoop command. E.g. if I want to point it to a specific config file I'd run:

hadoop org.apache.hadoop.hdfs.server.namenode.NNThroughputBenchmark -conf /home/shv/conf/my-hdfs-site.xml -op create -threads 200 -files 500000 -filesPerDir 100

LMK if it works for you.

+1. LGTM. Thanks Konstantin!

Just fyi, for other people trying this test, I had to set dfs.namenode.fs-limits.min-block-size to 16 in my hdfs-site.xml because BLOCK_SIZE = 16; in the code, otherwise the test would hang indefinitely.

Ravi you got a good point. I was running in the test environment, which turns off minimum block size verification automatically. The new patch sets DFS_NAMENODE_MIN_BLOCK_SIZE_KEY = 0 for the benchmark.

-1 overall. Here are the results of testing the latest attachment
http://issues.apache.org/jira/secure/attachment/12597531/NNThBenchTool.patch
against trunk revision .

-1 patch. Trunk compilation may be broken.

Console output: https://builds.apache.org/job/PreCommit-HDFS-Build/4804//console

This message is automatically generated.

-1 overall. Here are the results of testing the latest attachment
http://issues.apache.org/jira/secure/attachment/12597531/NNThBenchTool.patch
against trunk revision .

-1 patch. Trunk compilation may be broken.

Console output: https://builds.apache.org/job/PreCommit-HDFS-Build/4806//console

This message is automatically generated.

Thanks Konstantin! My +1 stands!

Committed this to trunk and branch-2.3. Will move it further down if requested.

SUCCESS: Integrated in Hadoop-trunk-Commit #4262 (See https://builds.apache.org/job/Hadoop-trunk-Commit/4262/)
HDFS-5068. Convert NNThroughputBenchmark to a Tool to allow generic options. Contributed by Konstantin Shvachko. (shv: http://svn.apache.org/viewcvs.cgi/?root=Apache-SVN&view=rev&rev=1514114)

• /hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
• /hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/NNThroughputBenchmark.java

SUCCESS: Integrated in Hadoop-Yarn-trunk #302 (See https://builds.apache.org/job/Hadoop-Yarn-trunk/302/)
HDFS-5068. Convert NNThroughputBenchmark to a Tool to allow generic options. Contributed by Konstantin Shvachko. (shv: http://svn.apache.org/viewcvs.cgi/?root=Apache-SVN&view=rev&rev=1514114)

• /hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
• /hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/NNThroughputBenchmark.java

FAILURE: Integrated in Hadoop-Hdfs-trunk #1492 (See https://builds.apache.org/job/Hadoop-Hdfs-trunk/1492/)
HDFS-5068. Convert NNThroughputBenchmark to a Tool to allow generic options. Contributed by Konstantin Shvachko. (shv: http://svn.apache.org/viewcvs.cgi/?root=Apache-SVN&view=rev&rev=1514114)

• /hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
• /hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/NNThroughputBenchmark.java

FAILURE: Integrated in Hadoop-Mapreduce-trunk #1519 (See https://builds.apache.org/job/Hadoop-Mapreduce-trunk/1519/)
HDFS-5068. Convert NNThroughputBenchmark to a Tool to allow generic options. Contributed by Konstantin Shvachko. (shv: http://svn.apache.org/viewcvs.cgi/?root=Apache-SVN&view=rev&rev=1514114)

• /hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
• /hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/NNThroughputBenchmark.java

Merged into branch 2.3