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Posted to commits@accumulo.apache.org by bu...@apache.org on 2014/05/06 17:28:36 UTC
svn commit: r908195 - in /websites/staging/accumulo/trunk/content: ./
release_notes/1.6.0.html
Author: buildbot
Date: Tue May 6 15:28:36 2014
New Revision: 908195
Log:
Staging update by buildbot for accumulo
Modified:
websites/staging/accumulo/trunk/content/ (props changed)
websites/staging/accumulo/trunk/content/release_notes/1.6.0.html
Propchange: websites/staging/accumulo/trunk/content/
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--- cms:source-revision (original)
+++ cms:source-revision Tue May 6 15:28:36 2014
@@ -1 +1 @@
-1592773
+1592779
Modified: websites/staging/accumulo/trunk/content/release_notes/1.6.0.html
==============================================================================
--- websites/staging/accumulo/trunk/content/release_notes/1.6.0.html (original)
+++ websites/staging/accumulo/trunk/content/release_notes/1.6.0.html Tue May 6 15:28:36 2014
@@ -192,8 +192,7 @@ Latest 1.4 release: <strong>1.4.5</stron
<h1 class="title">Release Notes for Apache Accumulo 1.6.0</h1>
- <p><strong>DRAFT 1.6.0 RELEASE NOTES</strong></p>
-<p>Apache Accumulo 1.6.0 adds some major new features and fixes many bugs. This release contains changes from 609 issues contributed by 36 contributors and committers. </p>
+ <p>Apache Accumulo 1.6.0 adds some major new features and fixes many bugs. This release contains changes from 609 issues contributed by 36 contributors and committers. </p>
<p>Accumulo 1.6.0 runs on Hadoop 1, however Hadoop 2 with HA namenode is recommended for production systems. In addition to HA, Hadoop 2 also offers better data durability guarantees, in the case when nodes lose power, than Hadoop 1.</p>
<h2 id="notable-improvements">Notable Improvements</h2>
<h3 id="multiple-volume-support">Multiple volume support</h3>
@@ -211,9 +210,9 @@ Latest 1.4 release: <strong>1.4.5</stron
<p>The only built in test that conditional mutations support are equality and isNull. However, iterators can be configured on a conditional mutation to run before these test. This makes it possible to implement any number of test such as less than, greater than, contains, etc.</p>
<h3 id="encryption">Encryption</h3>
<p>Encryption is still an experimental feature, but much progress has been made since 1.5.0. Support for encrypting rfiles and write ahead logs were added in <a href="https://issues.apache.org/jira/browse/ACCUMULO-958" title="Support pluggable encryption in walogs">ACCUMULO-958</a> and <a href="https://issues.apache.org/jira/browse/ACCUMULO-980" title="Support pluggable codecs for RFile">ACCUMULO-980</a>. Support for encrypting data over the wire using SSL was added in <a href="https://issues.apache.org/jira/browse/ACCUMULO-1009" title="Support encryption over the wire">ACCUMULO-1009</a>.</p>
-<p>When a tablet server fails, its write ahead logs are sorted and stored in HDFS. In 1.6.0, encrypting these sorted write ahead logs is not supported. <a href="https://issues.apache.org/jira/browse/ACCUMULO-981" title="support pluggable encryption when recovering write-ahead logs">ACCUMULO-981</a> addresses this issue. </p>
+<p>When a tablet server fails, its write ahead logs are sorted and stored in HDFS. In 1.6.0, encrypting these sorted write ahead logs is not supported. <a href="https://issues.apache.org/jira/browse/ACCUMULO-981" title="support pluggable encryption when recovering write-ahead logs">ACCUMULO-981</a> is open to address this issue. </p>
<h3 id="pluggable-compaction-strategies">Pluggable compaction strategies</h3>
-<p>One of the key elements of the <a href="http://research.google.com/archive/bigtable.html">BigTable</a> design is use of the <a href="http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.44.2782&rep=rep1&type=pdf">Log Structured Merge Tree</a>. This entails sorting data in memory, writing out sorted files, and then later merging multiple sorted files into a single file. These automatic merges happen in the background and Accumulo decides when to merge files based comparing relative sizes of files to a compaction ratio. Adjusting the compaction ratio is the only way a user can control this process. <a href="https://issues.apache.org/jira/browse/ACCUMULO-1451" title="Make Compaction triggers extensible">ACCUMULO-1451</a> introduces pluggable compaction strategies which allow users to choose when and what files to compact. <a href="https://issues.apache.org/jira/browse/ACCUMULO-1808" title="Create compaction strategy that has size limit">ACCUMULO-1808</a> adds a com
paction strategy the prevents compaction of files over a configurable size.</p>
+<p>One of the key elements of the <a href="http://research.google.com/archive/bigtable.html">BigTable</a> design is use of the <a href="http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.44.2782&rep=rep1&type=pdf">Log Structured Merge Tree</a>. This entails sorting data in memory, writing out sorted files, and then later merging multiple sorted files into a single file. These automatic merges happen in the background and Accumulo decides when to merge files based comparing relative sizes of files to a compaction ratio. Before 1.6.0 adjusting the compaction ratio was the only way a user could control this process. <a href="https://issues.apache.org/jira/browse/ACCUMULO-1451" title="Make Compaction triggers extensible">ACCUMULO-1451</a> introduces pluggable compaction strategies which allow users to choose when and what files to compact. <a href="https://issues.apache.org/jira/browse/ACCUMULO-1808" title="Create compaction strategy that has size limit">ACCUMULO-180
8</a> adds a compaction strategy that prevents compaction of files over a configurable size.</p>
<h3 id="lexicoders">Lexicoders</h3>
<p>Accumulo only sorts data lexicographically. Getting something like a pair of (<em>String</em>,<em>Integer</em>) to sort correctly in Accumulo is tricky. It's tricky because you only want to compare the integers if the strings are equal. It's possible to make this sort properly in Accumulo if the data is encoded properly, but can be difficult. To make this easier <a href="https://issues.apache.org/jira/browse/ACCUMULO-1336" title="Add lexicoders from Typo to Accumulo">ACCUMULO-1336</a> added Lexicoders to the Accumulo API. Lexicoders provide an easy way to serialize data so that it sorts properly lexicographically. Below is a simple example.</p>
<div class="codehilite"><pre> <span class="n">PairLexicoder</span> <span class="n">plex</span> <span class="p">=</span> <span class="n">new</span> <span class="n">PairLexicoder</span><span class="p">(</span><span class="n">new</span> <span class="n">StringLexicoder</span><span class="p">(),</span> <span class="n">new</span> <span class="n">IntegerLexicoder</span><span class="p">());</span>
@@ -230,7 +229,7 @@ Latest 1.4 release: <strong>1.4.5</stron
<h3 id="locality-groups-in-memory">Locality groups in memory</h3>
<p>In cases where a very small amount of data is stored in a locality group one would expect fast scans over that locality group. However this was not always the case because recently written data stored in memory was not partitioned by locality group. Therefore if a table had 100GB of data in memory and 1MB of that was in locality group A, then scanning A would have required reading all 100GB. <a href="https://issues.apache.org/jira/browse/ACCUMULO-112" title="Partition data in memory by locality group">ACCUMULO-112</a> changes this and partitions data by locality group as its written.</p>
<h3 id="service-ip-addresses">Service IP addresses</h3>
-<p>Previous versions of Accumulo always used IP addresses internally. This could be problematic in virtual machine environments where IP addresses change. In <a href="https://issues.apache.org/jira/browse/ACCUMULO-1585" title="Use FQDN/verbatim data from config files">ACCUMULO-1585</a> this was changed, now the accumulo uses the exact hostnames from its config files for internal addressing. </p>
+<p>Previous versions of Accumulo always used IP addresses internally. This could be problematic in virtual machine environments where IP addresses change. In <a href="https://issues.apache.org/jira/browse/ACCUMULO-1585" title="Use FQDN/verbatim data from config files">ACCUMULO-1585</a> this was changed, now Accumulo uses the exact hostnames from its config files for internal addressing. </p>
<p>All Accumulo processes running on a cluster are locatable via zookeeper. Therefore using well known ports is not really required. <a href="https://issues.apache.org/jira/browse/ACCUMULO-1664" title="Make all processes able to use random ports">ACCUMULO-1664</a> makes it possible to for all Accumulo processes to use random ports. This makes it easier to run multiple Accumulo instances on a single node. </p>
<p>While Hadoop <a href="http://wiki.apache.org/hadoop/HadoopIPv6">does not support IPv6 networks</a>, attempting to run on a system that does not have IPv6 completely disabled can cause strange failures. <a href="https://issues.apache.org/jira/browse/ACCUMULO-2262" title="Include java.net.preferIPv4Stack=true in process startup">ACCUMULO-2262</a> invokes the JVM-provided configuration parameter at process startup to prefer IPv4 over IPv6.</p>
<h3 id="viewfs">ViewFS</h3>