2017-07-05 17:04:26 -07:00
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==============
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Erasure coding
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==============
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Erasure coding is a set of algorithms that allows the reconstruction of
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missing data from a set of original data. In theory, erasure coding uses
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less capacity with similar durability characteristics as replicas.
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From an application perspective, erasure coding support is transparent.
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Object Storage (swift) implements erasure coding as a Storage Policy.
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2017-07-12 12:14:45 -07:00
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See :doc:`/overview_policies` for more details.
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2017-07-05 17:04:26 -07:00
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There is no external API related to erasure coding. Create a container using a
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Storage Policy; the interaction with the cluster is the same as any
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other durability policy. Because support implements as a Storage Policy,
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you can isolate all storage devices that associate with your cluster's
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erasure coding capability. It is entirely possible to share devices between
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storage policies, but for erasure coding it may make more sense to use
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not only separate devices but possibly even entire nodes dedicated for erasure
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coding.
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