9843767b21
Change-Id: I40999b1eb923fc3796cbb6d982e03d39cdf8c720 Implements: blueprint consistency-file-rename
32 lines
1.5 KiB
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32 lines
1.5 KiB
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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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See `Storage Policies
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<http://docs.openstack.org/developer/swift/overview_policies.html>`_
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for more details.
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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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.. important::
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The erasure code support in Object Storage is considered beta in Kilo.
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Most major functionality is included, but it has not been tested or
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validated at large scale. This feature relies on ``ssync`` for durability.
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We recommend deployers do extensive testing and not deploy production
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data using an erasure code storage policy.
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If any bugs are found during testing, please report them to
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https://bugs.launchpad.net/swift
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