35 lines
1.5 KiB
ReStructuredText
35 lines
1.5 KiB
ReStructuredText
.. _shared_file_systems_scheduling:
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==========
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Scheduling
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==========
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The Shared File Systems service uses a scheduler to provide unified
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access for a variety of different types of shared file systems. The
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scheduler collects information from the active shared services, and
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makes decisions such as what shared services will be used to create
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a new share. To manage this process, the Shared File Systems service
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provides Share types API.
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A share type is a list from key-value pairs called extra-specs. The
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scheduler uses required and un-scoped extra-specs to look up
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the shared service most suitable for a new share with the specified share type.
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For more information about extra-specs and their type, see `Capabilities
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and Extra-Specs <https://docs.openstack.org/manila/latest/admin
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/capabilities_and_extra_specs.html>`_ section in developer documentation.
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The general scheduler workflow:
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#. Share services report information about their existing pool number, their
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capacities, and their capabilities.
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#. When a request on share creation arrives, the scheduler picks a service
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and pool that best serves the request, using share type
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filters and back end capabilities. If back end capabilities pass through,
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all filters request the selected back end where the target pool resides.
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#. The share driver receives a reply on the request status, and lets the
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target pool serve the request as the scheduler instructs. The scoped
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and un-scoped share types are available for the driver implementation
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to use as needed.
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