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