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Posted to common-commits@hadoop.apache.org by ma...@apache.org on 2012/03/18 21:17:48 UTC

svn commit: r1302216 - in /hadoop/common/branches/branch-1: CHANGES.txt src/docs/releasenotes.html

Author: mattf
Date: Sun Mar 18 20:17:48 2012
New Revision: 1302216

URL: http://svn.apache.org/viewvc?rev=1302216&view=rev
Log:
preparing for release 1.0.2

Modified:
    hadoop/common/branches/branch-1/CHANGES.txt   (contents, props changed)
    hadoop/common/branches/branch-1/src/docs/releasenotes.html

Modified: hadoop/common/branches/branch-1/CHANGES.txt
URL: http://svn.apache.org/viewvc/hadoop/common/branches/branch-1/CHANGES.txt?rev=1302216&r1=1302215&r2=1302216&view=diff
==============================================================================
--- hadoop/common/branches/branch-1/CHANGES.txt (original)
+++ hadoop/common/branches/branch-1/CHANGES.txt Sun Mar 18 20:17:48 2012
@@ -161,7 +161,7 @@ Release 1.1.0 - unreleased
 
     MAPREDUCE-2835. Make per-job counter limits configurable. (tomwhite)
 
-Release 1.0.2 - unreleased
+Release 1.0.2 - 2012.03.18
 
   NEW FEATURES
 

Propchange: hadoop/common/branches/branch-1/CHANGES.txt
------------------------------------------------------------------------------
  Merged /hadoop/common/branches/branch-1.0/CHANGES.txt:r1302214

Modified: hadoop/common/branches/branch-1/src/docs/releasenotes.html
URL: http://svn.apache.org/viewvc/hadoop/common/branches/branch-1/src/docs/releasenotes.html?rev=1302216&r1=1302215&r2=1302216&view=diff
==============================================================================
--- hadoop/common/branches/branch-1/src/docs/releasenotes.html (original)
+++ hadoop/common/branches/branch-1/src/docs/releasenotes.html Sun Mar 18 20:17:48 2012
@@ -2,7 +2,7 @@
 <html>
 <head>
 <META http-equiv="Content-Type" content="text/html; charset=UTF-8">
-<title>Hadoop 1.0.0 Release Notes</title>
+<title>Hadoop 1.0.2 Release Notes</title>
 <STYLE type="text/css">
 		H1 {font-family: sans-serif}
 		H2 {font-family: sans-serif; margin-left: 7mm}
@@ -10,10 +10,231 @@
 	</STYLE>
 </head>
 <body>
-<h1>Hadoop 1.0.0 Release Notes</h1>
+<h1>Hadoop 1.0.2 Release Notes</h1>
 		These release notes include new developer and user-facing incompatibilities, features, and major improvements. 
 
 <a name="changes"/>
+
+<h2>Changes since Hadoop 1.0.1</h2>
+
+<h3>Jiras with Release Notes (describe major or incompatible changes)</h3>
+<ul>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-1722">HADOOP-1722</a>.
+     Major improvement reported by runping and fixed by klbostee <br>
+     <b>Make streaming to handle non-utf8 byte array</b><br>
+     <blockquote>                                              Streaming allows binary (or other non-UTF8) streams.
+
+      
+</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/MAPREDUCE-3851">MAPREDUCE-3851</a>.
+     Major bug reported by kihwal and fixed by tgraves (tasktracker)<br>
+     <b>Allow more aggressive action on detection of the jetty issue</b><br>
+     <blockquote>                    added new configuration variables to control when TT aborts if it sees a certain number of exceptions:
<br/>
+
+
<br/>
+
+&nbsp;&nbsp;&nbsp;&nbsp;// Percent of shuffle exceptions (out of sample size) seen before it&#39;s
<br/>
+
+&nbsp;&nbsp;&nbsp;&nbsp;// fatal - acceptable values are from 0 to 1.0, 0 disables the check.
<br/>
+
+&nbsp;&nbsp;&nbsp;&nbsp;// ie. 0.3 = 30% of the last X number of requests matched the exception,
<br/>
+
+&nbsp;&nbsp;&nbsp;&nbsp;// so abort.
<br/>
+
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;conf.getFloat(
<br/>
+
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&quot;mapreduce.reduce.shuffle.catch.exception.percent.limit.fatal&quot;, 0);
<br/>
+
+
<br/>
+
+&nbsp;&nbsp;&nbsp;&nbsp;// The number of trailing requests we track, used for the fatal
<br/>
+
+&nbsp;&nbsp;&nbsp;&nbsp;// limit calculation
<br/>
+
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;conf.getInt(&quot;mapreduce.reduce.shuffle.catch.exception.sample.size&quot;, 1000);
+</blockquote></li>
+
+</ul>
+
+<h3>Other Jiras (describe bug fixes and minor changes)</h3>
+<ul>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-5450">HADOOP-5450</a>.
+     Blocker improvement reported by klbostee and fixed by klbostee <br>
+     <b>Add support for application-specific typecodes to typed bytes</b><br>
+     <blockquote>For serializing objects of types that are not supported by typed bytes serialization, applications might want to use a custom serialization format. Right now, typecode 0 has to be used for the bytes resulting from this custom serialization, which could lead to problems when deserializing the objects because the application cannot know if a byte sequence following typecode 0 is a customly serialized object or just a raw sequence of bytes. Therefore, a range of typecodes that are treated as ali...</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-7206">HADOOP-7206</a>.
+     Major new feature reported by eli and fixed by tucu00 <br>
+     <b>Integrate Snappy compression</b><br>
+     <blockquote>Google release Zippy as an open source (APLv2) project called Snappy (http://code.google.com/p/snappy). This tracks integrating it into Hadoop.<br><br>{quote}<br>Snappy is a compression/decompression library. It does not aim for maximum compression, or compatibility with any other compression library; instead, it aims for very high speeds and reasonable compression. For instance, compared to the fastest mode of zlib, Snappy is an order of magnitude faster for most inputs, but the resulting compressed ...</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-8050">HADOOP-8050</a>.
+     Major bug reported by kihwal and fixed by kihwal (metrics)<br>
+     <b>Deadlock in metrics</b><br>
+     <blockquote>The metrics serving thread and the periodic snapshot thread can deadlock.<br>It happened a few times on one of namenodes we have. When it happens RPC works but the web ui and hftp stop working. I haven&apos;t look at the trunk too closely, but it might happen there too.</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-8088">HADOOP-8088</a>.
+     Major bug reported by kihwal and fixed by  (security)<br>
+     <b>User-group mapping cache incorrectly does negative caching on transient failures</b><br>
+     <blockquote>We&apos;ve seen a case where some getGroups() calls fail when the ldap server or the network is having transient failures. Looking at the code, the shell-based and the JNI-based implementations swallow exceptions and return an empty or partial list. The caller, Groups#getGroups() adds this likely empty list into the mapping cache for the user. This will function as negative caching until the cache expires. I don&apos;t think we want negative caching here, but even if we do, it should be intelligent eno...</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-8090">HADOOP-8090</a>.
+     Major improvement reported by gkesavan and fixed by gkesavan <br>
+     <b>rename hadoop 64 bit rpm/deb package name</b><br>
+     <blockquote>change hadoop rpm/deb name from hadoop-&lt;version&gt;.amd64.rpm/deb hadoop-&lt;version&gt;.x86_64.rpm/deb   </blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-8132">HADOOP-8132</a>.
+     Major bug reported by arpitgupta and fixed by arpitgupta <br>
+     <b>64bit secure datanodes do not start as the jsvc path is wrong</b><br>
+     <blockquote>64bit secure datanodes were looking for /usr/libexec/../libexec/jsvc. instead of /usr/libexec/../libexec/jsvc.amd64</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HDFS-2701">HDFS-2701</a>.
+     Major improvement reported by eli and fixed by eli (name-node)<br>
+     <b>Cleanup FS* processIOError methods</b><br>
+     <blockquote>Let&apos;s rename the various &quot;processIOError&quot; methods to be more descriptive. The current code makes it difficult to identify and reason about bug fixes. While we&apos;re at it let&apos;s remove &quot;Fatal&quot; from the &quot;Unable to sync the edit log&quot; log since it&apos;s not actually a fatal error (this is confusing to users). And 2NN &quot;Checkpoint done&quot; should be info, not a warning (also confusing to users).<br><br>Thanks to HDFS-1073 these issues don&apos;t exist on trunk or 23.</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HDFS-2702">HDFS-2702</a>.
+     Critical bug reported by eli and fixed by eli (name-node)<br>
+     <b>A single failed name dir can cause the NN to exit </b><br>
+     <blockquote>There&apos;s a bug in FSEditLog#rollEditLog which results in the NN process exiting if a single name dir has failed. Here&apos;s the relevant code:<br><br>{code}<br>close()  // So editStreams.size() is 0 <br>foreach edits dir {<br>  ..<br>  eStream = new ...  // Might get an IOE here<br>  editStreams.add(eStream);<br>} catch (IOException ioe) {<br>  removeEditsForStorageDir(sd);  // exits if editStreams.size() &lt;= 1  <br>}<br>{code}<br><br>If we get an IOException before we&apos;ve added two edits streams to the list we&apos;ll exit, eg if there&apos;s an ...</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HDFS-2703">HDFS-2703</a>.
+     Major bug reported by eli and fixed by eli (name-node)<br>
+     <b>removedStorageDirs is not updated everywhere we remove a storage dir</b><br>
+     <blockquote>There are a number of places (FSEditLog#open, purgeEditLog, and rollEditLog) where we remove a storage directory but don&apos;t add it to the removedStorageDirs list. This means a storage dir may have been removed but we don&apos;t see it in the log or Web UI. This doesn&apos;t affect trunk/23 since the code there is totally different.</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HDFS-2978">HDFS-2978</a>.
+     Major new feature reported by atm and fixed by atm (name-node)<br>
+     <b>The NameNode should expose name dir statuses via JMX</b><br>
+     <blockquote>We currently display this info on the NN web UI, so users who wish to monitor this must either do it manually or parse HTML. We should publish this information via JMX.</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HDFS-3006">HDFS-3006</a>.
+     Major bug reported by bcwalrus and fixed by szetszwo (name-node)<br>
+     <b>Webhdfs &quot;SETOWNER&quot; call returns incorrect content-type</b><br>
+     <blockquote>The SETOWNER call returns an empty body. But the header has &quot;Content-Type: application/json&quot;, which is a contradiction (empty string is not valid json). This appears to happen for SETTIMES and SETPERMISSION as well.</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HDFS-3075">HDFS-3075</a>.
+     Major improvement reported by brandonli and fixed by brandonli (name-node)<br>
+     <b>Backport HADOOP-4885 to branch-1</b><br>
+     <blockquote>When a storage directory is inaccessible, namenode removes it from the valid storage dir list to a removedStorageDirs list. Those storage directories will not be restored when they become healthy again. <br><br>The proposed solution is to restore the previous failed directories at the beginning of checkpointing, say, rollEdits, by copying necessary metadata files from healthy directory to unhealthy ones. In this way, whenever a failed storage directory is recovered by the administrator, he/she can ...</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HDFS-3101">HDFS-3101</a>.
+     Major bug reported by wangzw and fixed by szetszwo (hdfs client)<br>
+     <b>cannot read empty file using webhdfs</b><br>
+     <blockquote>STEP:<br>1, create a new EMPTY file<br>2, read it using webhdfs.<br><br>RESULT:<br>expected: get a empty file<br>I got: {&quot;RemoteException&quot;:{&quot;exception&quot;:&quot;IOException&quot;,&quot;javaClassName&quot;:&quot;java.io.IOException&quot;,&quot;message&quot;:&quot;Offset=0 out of the range [0, 0); OPEN, path=/testFile&quot;}}<br><br>First of all, [0, 0) is not a valid range, and I think read a empty file should be OK.</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/MAPREDUCE-764">MAPREDUCE-764</a>.
+     Blocker bug reported by klbostee and fixed by klbostee (contrib/streaming)<br>
+     <b>TypedBytesInput&apos;s readRaw() does not preserve custom type codes</b><br>
+     <blockquote>The typed bytes format supports byte sequences of the form {{&lt;custom type code&gt; &lt;length&gt; &lt;bytes&gt;}}. When reading such a sequence via {{TypedBytesInput}}&apos;s {{readRaw()}} method, however, the returned sequence currently is {{0 &lt;length&gt; &lt;bytes&gt;}} (0 is the type code for a bytes array), which leads to bugs such as the one described [here|http://dumbo.assembla.com/spaces/dumbo/tickets/54].</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/MAPREDUCE-3583">MAPREDUCE-3583</a>.
+     Critical bug reported by zhihyu@ebaysf.com and fixed by zhihyu@ebaysf.com <br>
+     <b>ProcfsBasedProcessTree#constructProcessInfo() may throw NumberFormatException</b><br>
+     <blockquote>HBase PreCommit builds frequently gave us NumberFormatException.<br><br>From https://builds.apache.org/job/PreCommit-HBASE-Build/553//testReport/org.apache.hadoop.hbase.mapreduce/TestHFileOutputFormat/testMRIncrementalLoad/:<br>{code}<br>2011-12-20 01:44:01,180 WARN  [main] mapred.JobClient(784): No job jar file set.  User classes may not be found. See JobConf(Class) or JobConf#setJar(String).<br>java.lang.NumberFormatException: For input string: &quot;18446743988060683582&quot;<br>	at java.lang.NumberFormatException.fo...</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/MAPREDUCE-3773">MAPREDUCE-3773</a>.
+     Major new feature reported by owen.omalley and fixed by owen.omalley (jobtracker)<br>
+     <b>Add queue metrics with buckets for job run times</b><br>
+     <blockquote>It would be nice to have queue metrics that reflect the number of jobs in each queue that have been running for different ranges of time.<br><br>Reasonable time ranges are probably 0-1 hr, 1-5 hr, 5-24 hr, 24+ hrs; but they should be configurable.</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/MAPREDUCE-3824">MAPREDUCE-3824</a>.
+     Critical bug reported by aw and fixed by tgraves (distributed-cache)<br>
+     <b>Distributed caches are not removed properly</b><br>
+     <blockquote>Distributed caches are not being properly removed by the TaskTracker when they are expected to be expired. </blockquote></li>
+
+</ul>
+
+<h2>Changes since Hadoop 1.0.0</h2>
+
+<h3>Jiras with Release Notes (describe major or incompatible changes)</h3>
+<ul>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-8009">HADOOP-8009</a>.
+     Critical improvement reported by tucu00 and fixed by tucu00 (build)<br>
+     <b>Create hadoop-client and hadoop-minicluster artifacts for downstream projects </b><br>
+     <blockquote>                    Generate integration artifacts &quot;org.apache.hadoop:hadoop-client&quot; and &quot;org.apache.hadoop:hadoop-minicluster&quot; containing all the jars needed to use Hadoop client APIs, and to run Hadoop MiniClusters, respectively.  Push these artifacts to the maven repository when mvn-deploy, along with existing artifacts. 
+</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-8037">HADOOP-8037</a>.
+     Blocker bug reported by mattf and fixed by gkesavan (build)<br>
+     <b>Binary tarball does not preserve platform info for native builds, and RPMs fail to provide needed symlinks for libhadoop.so</b><br>
+     <blockquote>                    This fix is marked &quot;incompatible&quot; only because it changes the bin-tarball directory structure to be consistent with the source tarball directory structure. The source tarball is unchanged. RPMs and DEBs now use an intermediate bin-tarball with an &quot;${os.arch}&quot; tag (like the packages themselves). The un-tagged bin-tarball is now multi-platform and retains the structure of the source tarball; it is in fact generated by target &quot;tar&quot;, not by target &quot;binary&quot;. Finally, in the 64-bit RPMs and DEBs, the native libs go in the &quot;lib64&quot; directory instead of &quot;lib&quot;.
+</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/MAPREDUCE-3184">MAPREDUCE-3184</a>.
+     Major improvement reported by tlipcon and fixed by tlipcon (jobtracker)<br>
+     <b>Improve handling of fetch failures when a tasktracker is not responding on HTTP</b><br>
+     <blockquote>                    The TaskTracker now has a thread which monitors for a known Jetty bug in which the selector thread starts spinning and map output can no longer be served. If the bug is detected, the TaskTracker will shut itself down. This feature can be disabled by setting mapred.tasktracker.jetty.cpu.check.enabled to false.
+</blockquote></li>
+
+</ul>
+
+<h3>Other Jiras (describe bug fixes and minor changes)</h3>
+<ul>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-7470">HADOOP-7470</a>.
+     Minor improvement reported by stevel@apache.org and fixed by enis (util)<br>
+     <b>move up to Jackson 1.8.8</b><br>
+     <blockquote>I see that hadoop-core still depends on Jackson 1.0.1 -but that project is now up to 1.8.2 in releases. Upgrading will make it easier for other Jackson-using apps that are more up to date to keep their classpath consistent.<br><br>The patch would be updating the ivy file to pull in the later version; no test</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-7960">HADOOP-7960</a>.
+     Major bug reported by gkesavan and fixed by mattf <br>
+     <b>Port HADOOP-5203 to branch-1, build version comparison is too restrictive</b><br>
+     <blockquote>hadoop services should not be using the build timestamp to verify version difference in the cluster installation. Instead it should use the source checksum as in HADOOP-5203.<br>  </blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-7964">HADOOP-7964</a>.
+     Blocker bug reported by kihwal and fixed by daryn (security, util)<br>
+     <b>Deadlock in class init.</b><br>
+     <blockquote>After HADOOP-7808, client-side commands hang occasionally. There are cyclic dependencies in NetUtils and SecurityUtil class initialization. Upon initial look at the stack trace, two threads deadlock when they hit the either of class init the same time.</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-7987">HADOOP-7987</a>.
+     Major improvement reported by devaraj and fixed by jnp (security)<br>
+     <b>Support setting the run-as user in unsecure mode</b><br>
+     <blockquote>Some applications need to be able to perform actions (such as launch MR jobs) from map or reduce tasks. In earlier unsecure versions of hadoop (20.x), it was possible to do this by setting user.name in the configuration. But in 20.205 and 1.0, when running in unsecure mode, this does not work. (In secure mode, you can do this using the kerberos credentials).</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-7988">HADOOP-7988</a>.
+     Major bug reported by jnp and fixed by jnp <br>
+     <b>Upper case in hostname part of the principals doesn&apos;t work with kerberos.</b><br>
+     <blockquote>Kerberos doesn&apos;t like upper case in the hostname part of the principals.<br>This issue has been seen in 23 as well as 1.0.</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-8010">HADOOP-8010</a>.
+     Minor bug reported by rvs and fixed by rvs (scripts)<br>
+     <b>hadoop-config.sh spews error message when HADOOP_HOME_WARN_SUPPRESS is set to true and HADOOP_HOME is present</b><br>
+     <blockquote>Running hadoop daemon commands when HADOOP_HOME_WARN_SUPPRESS is set to true and HADOOP_HOME is present produces:<br>{noformat}<br>  [: 76: true: unexpected operator<br>{noformat}</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HADOOP-8052">HADOOP-8052</a>.
+     Major bug reported by reznor and fixed by reznor (metrics)<br>
+     <b>Hadoop Metrics2 should emit Float.MAX_VALUE (instead of Double.MAX_VALUE) to avoid making Ganglia&apos;s gmetad core</b><br>
+     <blockquote>Ganglia&apos;s gmetad converts the doubles emitted by Hadoop&apos;s Metrics2 system to strings, and the buffer it uses is 256 bytes wide.<br><br>When the SampleStat.MinMax class (in org.apache.hadoop.metrics2.util) emits its default min value (currently initialized to Double.MAX_VALUE), it ends up causing a buffer overflow in gmetad, which causes it to core, effectively rendering Ganglia useless (for some, the core is continuous; for others who are more fortunate, it&apos;s only a one-time Hadoop-startup-time thi...</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HDFS-2379">HDFS-2379</a>.
+     Critical bug reported by tlipcon and fixed by tlipcon (data-node)<br>
+     <b>0.20: Allow block reports to proceed without holding FSDataset lock</b><br>
+     <blockquote>As disks are getting larger and more plentiful, we&apos;re seeing DNs with multiple millions of blocks on a single machine. When page cache space is tight, block reports can take multiple minutes to generate. Currently, during the scanning of the data directories to generate a report, the FSVolumeSet lock is held. This causes writes and reads to block, timeout, etc, causing big problems especially for clients like HBase.<br><br>This JIRA is to explore some of the ideas originally discussed in HADOOP-458...</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/HDFS-2814">HDFS-2814</a>.
+     Minor improvement reported by hitesh and fixed by hitesh <br>
+     <b>NamenodeMXBean does not account for svn revision in the version information</b><br>
+     <blockquote>Unlike the jobtracker where both the UI and jmx information report the version as &quot;x.y.z, r&lt;svn revision&quot;, in case of the namenode, the UI displays x.y.z and svn revision info but the jmx output only contains the x.y.z version.</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/MAPREDUCE-3343">MAPREDUCE-3343</a>.
+     Major bug reported by ahmed.radwan and fixed by zhaoyunjiong (mrv1)<br>
+     <b>TaskTracker Out of Memory because of distributed cache</b><br>
+     <blockquote>This Out of Memory happens when you run large number of jobs (using the distributed cache) on a TaskTracker. <br><br>Seems the basic issue is with the distributedCacheManager (instance of TrackerDistributedCacheManager in TaskTracker.java), this gets created during TaskTracker.initialize(), and it keeps references to TaskDistributedCacheManager for every submitted job via the jobArchives Map, also references to CacheStatus via cachedArchives map. I am not seeing these cleaned up between jobs, so th...</blockquote></li>
+
+<li> <a href="https://issues.apache.org/jira/browse/MAPREDUCE-3607">MAPREDUCE-3607</a>.
+     Major improvement reported by tomwhite and fixed by tomwhite (client)<br>
+     <b>Port missing new API mapreduce lib classes to 1.x</b><br>
+     <blockquote>There are a number of classes under mapreduce.lib that are not present in the 1.x series. Including these would help users and downstream projects using the new MapReduce API migrate to later versions of Hadoop in the future.<br><br>A few examples of where this would help:<br>* Sqoop uses mapreduce.lib.db.DBWritable and mapreduce.lib.input.CombineFileInputFormat (SQOOP-384).<br>* Mahout uses mapreduce.lib.output.MultipleOutputs (MAHOUT-822).<br>* HBase has a backport of mapreduce.lib.partition.InputSampler ...</blockquote></li>
+
+
+</ul>
+
+
 <h2>Changes since Hadoop 0.20.205.0</h2>
 
 <h3>Jiras with Release Notes (describe major or incompatible changes)</h3>