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2.1 KiB
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136 lines
2.1 KiB
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..
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This work is licensed under a Creative Commons Attribution 3.0 Unported
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License.
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http://creativecommons.org/licenses/by/3.0/legalcode
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==========================================
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Capacity-based QoS
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==========================================
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Include the URL of your launchpad blueprint:
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https://blueprints.launchpad.net/cinder/+spec/capacity-based-qos
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QoS values in Cinder currently are able to be set to static
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values. This work proposes a way to derive QoS limit values
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based on volume capacities rather than static values.
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Problem description
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===================
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This proposes a mechanism to provision IOPS on a per-volume basis with
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the IOPS values adjusted based on the volume's size. (IOPS per GB)
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Use Cases
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=========
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A deployer wishes to cap "usage" of this system to limits based
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on space usage as well as throughput, in order to bill customers
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and not exceed limits of the backend.
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Associating IOPS and size allows you to provide tiers such as
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Gold: 1000 GB at 10000 IOPS per GB
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Silver: 1000 GB at 5000 IOPS per GB
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Bronze: 500 GB at 5000 IOPS per GB
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Proposed change
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===============
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Allow creation of qos_keys:
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read_iops_sec_per_gb
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write_iops_sec_per_gb
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total_iops_sec_per_gb
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These function the same as our current <x>_iops_sec keys,
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except they are scaled by the volume size.
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Alternatives
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------------
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None
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Data model impact
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-----------------
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None
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REST API impact
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---------------
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None
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Security impact
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---------------
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None
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Notifications impact
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--------------------
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None
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Other end user impact
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---------------------
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None
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Performance Impact
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------------------
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None
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Other deployer impact
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---------------------
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New optional qos spec values.
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Off by default, opt-in.
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Developer impact
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----------------
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None
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Implementation
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==============
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Assignee(s)
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-----------
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Primary assignee:
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eharney
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Work Items
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----------
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* https://review.openstack.org/#/c/447127/
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Dependencies
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============
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Testing
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=======
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Documentation Impact
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====================
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Document new fields available in qos types.
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References
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==========
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Code: https://review.openstack.org/#/c/447127/
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