22 lines
821 B
ReStructuredText
22 lines
821 B
ReStructuredText
=========
|
|
Memcached
|
|
=========
|
|
|
|
Memcached is a general-purpose distributed memory caching system. It
|
|
is used to speed up dynamic database-driven websites by caching data
|
|
and objects in RAM to reduce the number of times an external data
|
|
source must be read.
|
|
|
|
Memcached is a memory cache demon that can be used by most OpenStack
|
|
services to store ephemeral data, such as tokens.
|
|
|
|
Access to Memcached is not handled by HAProxy because replicated
|
|
access is currently in an experimental state. Instead, OpenStack
|
|
services must be supplied with the full list of hosts running
|
|
Memcached.
|
|
|
|
The Memcached client implements hashing to balance objects among the
|
|
instances. Failure of an instance impacts only a percentage of the
|
|
objects and the client automatically removes it from the list of
|
|
instances. The SLA is several minutes.
|