Salvatore Sanfilippo summarizes the new Redis release in the Hacker News thread:

2.2 was exactly an “optimization” release, to bring what we had at a better level of maturity.

Basically we’ll try hard to don’t add things to the API in the next releases, but just to open to new use cases changing the “backend” part, with cluster support for large fault tolerant deployment, and with diskstore for “bigdata”.

However there are a few important new things in Redis 2.2 from the point of view of the features, I think the main ones are:

• non blocking replication, so that now slaves are able to serve data even when trying to resync with the master.
• Check and Set with WATCH.
• Write operations against keys with an expire set.
• LRU eviction of keys in ‘maxmemory’ mode.
• Support for SETBIT/GETBIT/SETRANGE/GETRANGE, basically this turn the string data type into a random access array.

The more verbose release notes are available here.

Redis 2.2 is a drop in replacement for the previous 2.0 version. Though there are some changes in the return values for edge cases.

Update: Minutes ago, Salvatore has announced that there will be a new release today to fix an urgent bug in SPOP.

Update: Redis 2.2.1 is out. You can get it from here.

Original title and link: Redis 2.2: An Optimization Release (NoSQL databases © myNoSQL)

Cassandra has pushed out two new minor releases, first of them, 0.7.1, featuring a couple of performance improvements and new features, and the second, 0.7.2, fixing a critical bug in the 0.7.1 release.

Cassandra 0.7.1 Performance Improvements

• Disk writes and sequential scans avoid polluting page cache (requires JNA to be enabled)
• Cassandra performs writes efficiently across datacenters by sending a single copy of the mutation and having the recipient forward that to other replicas in its datacenter.
• Improved network buffering
• Reduced lock contention on memtable flush
• Optimized supercolumn deserialization
• Zero-copy reads from mmapped sstable files
• Explicitly set higher JVM new generation size
• Reduced i/o contention during saving of caches

Cassandra 0.7.1 New Features

• added flush_largest_memtables_at and reduce_cache_sizes_at options to cassandra.yaml as an escape valve for memory pressure
• added option to specify -Dcassandra.join_ring=false on startup to allow “warm spare” nodes or performing JMX maintenance before joining the ring

The complete list of changes can be found here:

Original title and link: Cassandra Releases: Two Minor Upgrades (NoSQL databases © myNoSQL)

You’d assume that the more mature a project gets the less interesting a point release would be. But this doesn’t seem to apply to the NoSQL databases, where with each new release we are seeing new exciting features. Only from this month: Neo4j 1.2, Cassandra 0.7, HBase 0.90.0, and upcoming MongoDB 1.8.

After two attempts to announce CouchDB 1.0.2 back in December, both stopped in a very last moment by issues that the community considered mandatory to fix before the release, today the CouchDB people are finally announcing the availability of CouchDB 1.0.2.

You can find the list of changes in CouchDB 1.0.2 here:

• Significantly higher read and write throughput against database and view index files.
• Reduce lengthy stack traces.
• Allow reduce=false parameter in map-only views.
• Fix databases forgetting their validation function after compaction.
• Fix occasional timeout errors after successfully compacting large databases.
• Fix ocassional error when writing to a database that has just been compacted.
• Fix occasional timeout errors on systems with slow or heavily loaded IO.
• Fix for OOME when compactions include documents with many conflicts.
• Fix for missing attachment compression when MIME types included parameters.
• Preserve purge metadata during compaction to avoid spurious view rebuilds.
• Fix spurious conflicts introduced when uploading an attachment after a doc has been in a conflict. See COUCHDB-902 for details.
• Fix for frequently edited documents in multi-master deployments being duplicated in _changes and _all_docs. See COUCHDDB-968 for details on how to repair.
• Fix authenticated replication (with HTTP basic auth) of design documents with attachments.
• Various fixes to make replication more resilient for edge-cases.
• Don’t trigger view updates when requesting _design/doc/_info.
• Documents are now sealed before being passed to map functions.
• Force view compaction failure when duplicated document data exists. When this error is seen in the logs users should rebuild their views from scratch to fix the issue. See COUCHDB-999 for details.

Third attempt is always lucky! Congrats!

Original title and link: CouchDB 1.0.2: (NoSQL databases © myNoSQL)

As far as I know this is the first major HBase release since becoming a top level Apache project (this using a new versioning too). Until now I thought that Hadoop 0.21.0 had the longest list of fixes, improvements, and new features, but I guess HBase 0.90.0 tops that with over 1000 tracked tickets.

I bet there are quite a few exciting things among these over 1000 tickets, but for now I’d suggest taking a look at the slides below from HUG11:

From a slides, a quick what’s new in HBase 0.90.0:

• durability and stability
  • HDFS appends + WAL improvements
• master rewrite
  • cleanup of master, move region transitions to ZK
• inter-cluster/inter-DB replication
• Bloom filters
• bul loading improvements
• performance improvements
• peripheral improvements: REST/Stargate, Shell, Avro,
• HBaseFSCK

Note: HBase coprocessors are scheduled for 0.92

On a negative side, HBase 0.90.0 doesn’t run with Hadoop 0.21.0 nor with Hadoop TRUNK, the only compatible Hadoop version being 0.20.x. The release notes for HBase 0.90 release candidates are mentioning that HBase will lose data unless running on an Hadoop HDFS 0.20.x that has a durable sync. Though there is a Hadoop branch containing the necessary changes, but you’ll have to build that yourself. Update: see Nicolas’ comment below about Hadoop 0.21 being just a development version.

Congrats to the HBase team for their first release as top Apache project!

I didn’t know about the The Apache HBase book. But I’m eagerly awaiting my copy of Lars George’s HBase: The definitive guide.

Update: the official announcement went out

@ saintstack and @ squarecog

Original title and link: HBase 0.90.0 Released: Over 1000 Fixes and Improvements (NoSQL databases © myNoSQL)

Something I’ve missed from the what’s new in Cassandra 0.7:

The other big new feature is large row support for up to two billion columns per row. In previous Cassandra releases, there was a limit where a single column value could not be larger than 2 GB.

But number of columns vs size of columns data is quite different…

Original title and link: Cassandra 0.7: Large Row Support (NoSQL databases © myNoSQL)

Neo4j 1.2 was released on December 30th. Now that’s a very weird time to make a major release. But according to the Neo4j roadmap and milestone reports, Neo4j 1.2 brings quite a few major changes and improvements.

First major shift in Neo4j direction is that it is now available as a RESTful server. Even if a Neo4j REST API existed before, this shift from promoting an embedded graph database to a full blown RESTful graph database was firstly announced with the first 1.2 milestone. As someone suggesting this change, I cheer the decision.

The second major feature is the high availability Neo4j cluster. Most of the existing graph databases have started their life as embedded storage solutions. Then a few of them have seen the light of becoming server-based storage solutions. But with that also came questions related to availability and scalability.

Starting with this version, Neo4j offers the option of setting up a high availability cluster and this is a major step forward for graph databases. This is still a first version where writes are slower, the cluster is not elastic, and there are limitations at the distributed transaction layer.

Scaling graph databases remains a very complicated problem to be solved. Darren Wood’s¹ presentation covers some of the challenges of distributed graph databases

Neo4j 1.2 features a couple of more goodies like a smaller footprint kernel and an automatic JMX enabled monitoring and management component.

The original announcement covers more details about this major Neo4j new version. The only missing piece from this release and announcement is a document describing Neo4j API changes. But that should not stop you from trying it out.

Original title and link: Neo4j 1.2: What’s New (NoSQL databases © myNoSQL)

The much awaited new version of Cassandra has been quietly release a couple of days ago. As mentioned in Cassandra 2010 in review, this version brings a lot of interesting new features:

• memory efficient compactions
• online schema changes
• secondary indexes
• improved performance for reads
• upgraded Thrift

The list of updates is too long, so for start I recommend Gary Dusbabek’s nice post summarizing most important new features.

Then on Riptano’s blog, there’s a series of articles getting into the details of these features:

• Jonathan Ellis: Live schema updates
• Jonathan Ellis: Secondary indexes
• Brandon Williams: Hadoop output to Cassandra
• Sylvain Lebresne: Expiring columns

I guess the only major feature that was talked about and didn’t get in this release is the distributed counters, but that’s already in the Cassandra trunk, so sooner than later users will get it.

Now you can head to the download page and start upgrading your Cassandra cluster.

Original title and link: Cassandra 0.7 Released, Lots of Goodies in the Box (NoSQL databases © myNoSQL)

A bit late with the post, but here is Cascading 1.2:

This release features many performance and usability enhancements while remaining backwards compatible with 1.0 and 1.1. Specifically:

• Performance optimizations during grouping (StreamComparator)
• Composable map-side partial aggregations (AggregateBy)
• Native Riffle support for non-Cascading (or nested iterative Cascading) processes (ProcessFlow and Riffle)

Cascading is part of the extensive Hadoop tooling ecosystem.

Original title and link: Cascading 1.2 Released (NoSQL databases © myNoSQL)