Latest Features in MongoDB 3.4, Redis 3.2, HBase 1.2.4, Geode 1.0 & TiDB RC1

MongoDB 3.4

MongoDB 3.4 adds a set of major features for sharded clusters, replication, and data handling:

Sharding Zones – replaces tag‑aware sharding; data can be assigned to specific shards via configurable zones.

Faster balancing – with the WiredTiger storage engine the moveChunk command defaults secondaryThrottle to false, eliminating the wait for secondary replication. Parallel chunk migrations are allowed: a cluster with N shards can run up to N/2 concurrent moves.

Linearizable read concern – guarantees that a read sees data committed with majority write concern, but only for single‑document queries.

Improved initial sync – all indexes are built during the initial data copy, and the secondary continues pulling oplog entries to ensure sufficient local storage.

Decimal128 type – introduces a 128‑bit decimal with up to 34 fractional digits.

Aggregation enhancements – many new operators, notably $facet and $graphLookup.

Collation and case‑insensitive indexes – locale‑aware string comparison and the ability to create indexes that ignore case.

Read‑only views – virtual collections defined by a query can be queried like regular collections.

MongoDB Tools – the new mongoreplay utility records commands on a mongod instance and replays them on another instance, superseding mongosniff.

Redis 3.0 and 3.2

Redis 3.0 (GA 2015‑04‑01) stabilised the Redis Cluster architecture, providing high availability without a proxy and linear scalability to thousands of nodes. Key improvements include:

Faster AOF rewrite.

Upgraded LRU algorithm for better key eviction.

Accelerated key migration with COPY and REPLACE options.

Flexible memory configuration, e.g. CONFIG SET maxmemory 1gb. CLIENT PAUSE command to temporarily stop client processing.

Performance boost for INCR operations.

Redis 3.2 (latest 3.2.6, 2016‑12‑06) adds GEO support using sorted sets and introduces several optimisations:

Cluster migration speed up to 10× and improved slot rebalancing.

Significant API changes.

New BITFIELD command for bit‑field manipulation.

Reduced memory footprint for identical data values.

Lua script enhancements for replication and remote debugging.

Apache HBase 1.2.4

Release date: 2016‑11‑07. This fourth maintenance release of the 1.2.x line fixes 35 bugs. Notable JIRA items include:

[HBASE-14734] – MiniKDC bind exception fix.

[HBASE-15984] – Robust WAL replay for cleanly closed logs.

[HBASE-16101] – Procedure v2 performance tool for WAL.

[HBASE-16522] – Cache system user handling to avoid IOExceptions.

[HBASE-16970] – Clarified Scan caching comment.

[HBASE-15315] – Removed unnecessary super‑user high‑priority call.

[HBASE-16033] – More detailed logging for slow or large responses.

[HBASE-16667] – Build compatibility with JDK 8 (ignores MaxPermSize).

[HBASE-17165] – Added retry logic to LoadIncrementalHFiles tool.

Release notes: https://issues.apache.org/jira/secure/ReleaseNote.jspa?version=12338116&projectId=12310753

Binary download:

http://apache.fayea.com/hbase/1.2.4/hbase-1.2.4-bin.tar.gz

Apache Geode 1.0

Geode graduated to a top‑level Apache project on 2016‑11‑21. Key enhancements in version 1.0 are:

High‑availability improvements – multicast member discovery and automatic client‑side reconnection with data preservation during outages.

Management and monitoring tools – real‑time performance statistics and a command‑line interface for cluster administration.

Gateway load‑balancing API for distributed data routing.

Internal updates: Log4j 2 logging, strengthened SSL and LDAP configurations, PDX serialization aliasing, advanced query and index hints, batch processing for in‑memory data, and new REST API endpoints with SSL support.

Official site: http://geode.apache.org/

TiDB RC1 preview

TiDB is a distributed NewSQL database inspired by Google Spanner & F1, combining OLTP and OLAP workloads. The upcoming RC1 focuses on production readiness. Main improvements:

SQL optimizer enhancements – deeper operator push‑down for better MPP performance.

Faster bulk import using myloader / mydumper.

Stability upgrades and overload protection mechanisms.

Kubernetes integration for automated deployment and one‑click cluster orchestration.

Real‑time bi‑directional synchronization between TiDB and MySQL.

Documentation: https://github.com/pingcap/docs-cn

RethinkDB end‑of‑life

RethinkDB, an open‑source JSON‑document database launched in 2009, released its final stable version 2.3.2 on 2016‑05‑02. The project has been discontinued; the engineering team is expected to join Stripe.