Cloudera’s Charles Zedlewski gives a great explanation of the Apache Hadoop versioning and the major features included in each production-ready version:

Credit Cloudera. Click to see larger version

Patrick Durusau suggests an even shorter explanation:

There has been some confusion over the jump from 0.2* versions of Hadoop to a release of Hadoop 1.0 at Apache.

You have not missed various 0.3* and later releases!

People familiar with open source projects know that most of the time versions do not carry any meta-information about the maturity of a project. But the higher you go into an enterprise hierarchy the more important software versions are considered. So sometimes it is a good idea to bump up the numbers to something that is perceived by everyone as a mature version. Adoption is sometimes also about perception.

Original title and link: Apache Hadoop Versions (NoSQL database©myNoSQL)

Let’s start the year with a quick review of the latest releases that happened in December. Make sure that you scroll to the end as there are quite a few important ones.

MongoDB 2.0.2

Announced on Dec.15th, MongoDB 2.0.2 is a bug fix release:

• Hit config server only once per mongos on meta data change to not overwhelm
• Removed unnecessary connection close and open between mongos and mongod after getLastError
• Replica set primaries close all sockets on stepDown()
• Do not require authentication for the buildInfo command
• scons option for using system libraries

Apache Hive 0.8.0

Apache Hive 0.8.0 came out on Dec.19th. The list of new features, improvements, and bug fixes is extremely long.

Just as a side note, who came out with the idea of having a Hive fans’ page on Facebook?

Apache ZooKeeper 3.4.2

ZooKeeper 3.4.0 has been followed up shortly by two new minor version updates fixing some critical bugs. The list of issues fixed in ZooKeeper 3.4.1 can be found here and for ZooKeeper 3.4.2 the 2 fixed bugs are listed here.

As with ZooKeeper 3.4.0, these versions are not yet production ready.

Apache Whirr 0.7.0

Apache Whirr 0.7.0 has been released on Dec.21st featuring 56 improvements and bug fixes including support for Puppet & Chef, and Mahout and Ganglia as a service. The complete list can be found here.

Some more details about Whirr 0.7.0 can be found here.

Apache HBase 0.90.5

Released Dec.23rd, HBase 0.90.5 packs 81 bug fixes. The complete list can be found here.

Redis 2.4.5

Redis 2.4.5 was released on Dec.23rd and provides 4 bug fixes:

• [BUGFIX] Fixed a ZUNIONSTORE/ZINTERSTORE bug that can cause a NaN to be inserted as a sorted set element score. This happens when one of the elements has +inf/-inf score and the weight used is 0.
• [BUGFIX] Fixed memory leak in CLIENT INFO.
• [BUGFIX] Fixed a non critical SORT bug (Issue 224).
• [BUGFIX] Fixed a replication bug: now the timeout configuration is respected during the connection with the master.
• --quiet option implemented in the Redis test.

Last but definitely one of the most important announcements that came in December:

Hadoop 1.0.0

Based on the 0.20-security code line, Hadoop 1.0.0 was announced on Dec.29. This release includes support for:

• HBase (append/hsynch/hflush) and Security
• Webhdfs (with full support for security)
• Performance enhanced access to local files for HBase
• Other performance enhancements, bug fixes, and features
• All version 0.20.205 and prior 0.20.2xx features

Complete release notes are available here.

Stéphane Fréchette, Ryan Slobojan, Duane Moore, Arun C. Murthy

And with this we are ready for 2012.

Original title and link: Last NoSQL Releases in 2011: MongoDB, Hive, ZooKeeper, Whirr, HBase, Redis, and Hadoop 1.0.0 (NoSQL database©myNoSQL)

Apache ZooKeeper, the high-performance coordination service exposing services like naming, configuration management, synchronization, etc. for distributed applications, has reached version 3.4.0.

Even if the official announcement was laconic, ZooKeeper 3.4.0 features over 150 fixes.

The most important ones are summarized by Patrick Hunt in this Cloudera blog post:

• ZooKeeper 3.3.3 clients are compatible with 3.4.0 servers
• Native Windows version of C client
• Support Kerberos authentication of clients
• Support Kerberos authentication of clients
• Improved REST Interface
• Existing monitoring support has been extended through the introduction of a new ‘mntr’ 4 letter word
• Add tools and recipes for monitoring as a contrib
• Web-based Administrative Interface
• Automating log and snapshot cleaning
• Add logging/stats to identify production deployment issues
• Support for building RPM and DEB packages

Something to keep in mind though: ZooKeeper 3.4.0 is not production ready yet. After extensive testing, it will be followed soon by a minor release that will be production-ready.

Original title and link: Apache ZooKeeper 3.4.0 Released to Be Followed Soon by Production-Ready Version (NoSQL database©myNoSQL)

A new version of Redis is available for download and it is a recommended upgrade for all users as it addresses a potentially serious issue in jemalloc.

The complete list of changes:

• [BUGFIX] jemalloc upgraded to version 2.2.5, previous versions had a potentially serious issue when allocating big memory areas, something that Redis actually does. However we never received bug reports that appear to be caused by jemalloc.
• [BUGFIX] DISCARD now clears DIRTY_CAS flag in the client. Now the next transaction will not fail if the previous transaction used WATCH and the key was touched.
• CLIENT LIST output modified to include the last command executed by clients.
• Better bug report on crash.
• Protocol errors are now logged for loglevel >= verbose.
• Two new INFO fields related to AOF, that can be useful when investigating Redis issues.

Original title and link: Redis 2.4.4 Released Fixes Potential Issue in Jemalloc (NoSQL database©myNoSQL)