membase-A distributed key-value database for modern web applications

如果应用中用了memcached,那么毫无疑问可以用membase来持久存储！

http://membase.org/

Membase is an open-source (Apache 2.0 license) distributed, key-value database management system optimized for storing data behind interactive web applications. These applications must service many concurrent users; creating, storing, retrieving, aggregating, manipulating and presenting data in real-time. Supporting these requirements, membase processes data operations with quasi-deterministic low latency and high sustained throughput. It scales linearly from a single-server deployment to a cluster of thousands of machines. And because membase does not require creation of a schema before storing data, it is a flexible, cost-effective place to Store Lots of Stuff. The original membase source code was released as Open Source by NorthScale, Zynga and NHN to membase.org in June 2010.

For those familiar with memcached, membase provides on-the-wire protocol compatibility, but adds disk persistence; hierarchical storage management; data replication; live cluster reconfiguration and rebalancing; and secure multi-tenancy with data partitioning. Like memcached, membase is simple, fast and elastic.

Simple. Membase is extremely easy to manage, and simple to develop against. Every node is alike in a membase cluster – clone a node, join it to the cluster and press the rebalance button to automatically rebalance data to it. Membase enjoys the widest language and application framework support of any NoSQL database technology due to its on-the-wire protocol compatibility with memcached; in fact, membase directly incorporates memcached “front end” source code, leveraging the memcached engine interface, guaranteeing compatibility today and in to the future.

Fast. Membase distributes data and data operation I/O across commodity servers (or VMs), replicates data for high-availability, transparently caches data in main memory, persists the data using a multi-tier storage management model (supporting both on- and off-node SSD and spinning disk media), and auto-migrates data to the lowest-latency storage tier in response to observed data access patterns. It is a consistently low-latency and high-throughput processor of data operations. It is multi-threaded, with low lock contention; it automatically de-duplicates writes and is internally asynchronous everywhere possible.

Elastic. Membase scales elastically, with linear cost. Servers can be added to, or removed from, a running cluster with no application downtime. Employing commodity servers, virtual machines or cloud machine instances, data management resources can be dynamically matched to the needs of an application with little effort.