Memcached is a high-performance, distributed memory object caching system used by a number of large Internet sites such as Wikipedia, Flickr, Twitter, and Youtube, as well as enterprise systems.
Memcached offers the following advantages over other caching systems:
Better utilization of memory resources from the server farm.
No replication (and therefore no overhead involved in replication). This results in a reduction of 60 or more threads per Vibe node in a two-node cluster.
The number of servers and the size of data scale together.
Scales out much better than replication-based cluster cache.
Vibe supports memcached only on the SUSE Linux operating system.