Voldemort

Voldemort is written in Java and was developed by LinkedIn.

It is not a classic relational database, being more close to NoSQL systems like Redis or FlockDB rather than to MySQL.

Voldemort is for managing large amounts of data on multiple servers at once.

It's usually the kind of database you use only when developing portal-like websites that need to be fast in above average query loads and high traffic conditions.

Features:

• Data replication
• Data partionioning
• Support for replication across multiple servers
• Support for partioning across multiple servers
• Fault-tolerant
• Serialization support
• Each data storage node is independent from the others
• Data versioning
• Node performance can be tweaked on an individual level
• In-memory & On-memory caching
• Scalable system
• Easy testing procedures
• Documentation

What is new in this release:

• Bug fix for diverging metadata versions.
• IntelliJ support in gradle build.
• Avoid extra allocation on AvroGenericVersioned.
• Unit test fixes.

What is new in version 1.9.5:

• Version metadata key fix for incorrectly incrementing on each restarts
• ReplaceNodeCLI fixes and adding post conditions.
• Tests refactoring and a new class ClientTrafficGenerator for sending traffic
• Fixed Cluster.equals to do the node state check
• Enhanced meta check-version to do the auto analysis and give output
• Readonly replication helper tool to output, to boot strap the dead node
• Windows batch file equivalents for new command functionality
• DeleteKeysCLI tool to delete the serialized keys from Voldemort
• Krati entries iterator bug fix

What is new in version 1.9.4:

• Added separate failure detector for slop pusher job so that metadata slop.streaming.enabled functions.
• Renamed StoreVerifier to ConnectionVerifier.
• Create AdminConnectionVerifier and AdminSlopStreamingVerifier for failure detectors under OFFLINE_SERVER.

What is new in version 1.9.1:

• Admin service and client for Coordinator
• Some refactoring
• Fixed getmetadata shell command
• Fixed origin time in coordinator rest request

What is new in version 1.8.3:

• Added overwrite option to fork lift tool
• Added debug log messages for CoordinatorService
• Added jUnit support for gradle
• Fixed NetworkClassLoader bug when running in Windows OS
• Fixed bind failures while running tests
• Used standard logger in the StreamingClient constructor

What is new in version 1.8.1:

• Fix AbstractStoreClientFactory for backwards compatibility
• Cleaned up logging messages
• Unit tests for big Binary data
• Refactored voldemort admin tool - Phase 1 and Phase 2

What is new in version 1.8.0:

• Split the stores.xml into individual stores on Voldemort server.
• Maintaing backwards compatibility of MetadataStore.
• DefaultStoreClient bootstraps using store name (instead of stores.xml).
• New Admin tool functionality to update stores (instead of replace).

What is new in version 1.6.9:

• Fix a big where StreamingClient will throw NPE if not initialized
• Fix multiple broken tests
• Modified RO Rebalance Test to cover one more case
• Adding thin client shell for Voldemort Coordinator
• Move to tusk-0.0.2

What is new in version 1.6.7:

• Updating the ivy file to refer to tusk-0.0.2.

What is new in version 1.6.5:

• Adding AdminClient functionality to update store definitions.

What is new in version 1.6.4:

• Fixed bug when RO server NPE when rolled back
• RO bug fix caused by RW optimization code

What is new in version 1.6.2:

• Slops stored for nodes no longer in cluster, will die automatically
• Admin command to selectively purge slops destined to nodes/zones/stores
• Admin command to atomically update cluster.xml, stores.xml in one go
• Added admin command show-routing-plan to trace routing table for a key
• ZoneClipperCLI also adjusts store definitions based on dropped zone
• Numerous tests around non contiguous node ids/zone IDs

What is new in version 1.6.0:

• Changes:
• Fixes to remove dependency on non contiguous node IDs
• Stats for store client

What is new in version 1.5.8:

• Replaced resthdfs jar with tusk.jar.
• Incorporates retries into rest hdfs fetcher.

What is new in version 1.5.2:

• Client side visibility changes (Histogram, Connect exception)
• Adding PruneJob and timebased resolving mechanism to streaming client
• R2Store cleanup required for the rest client
• Monitoring improvements (aggregated BDB stats, streaming stats)
• Monitoring and Config improvements for REST service
• Removed donor based rebalancing code
• Removed replica type from the code base
• Improvements to Rebalance controller

What is new in version 1.4.6:

• Cleanup of R2Store to work with the REST server
• Modified ZenStoreClient to avoid creating SystemStores during each
• Re-bootstrap
• Added slop streaming functionality