9dcf71381a
Scrubbing the backlog directory. This spec has been here since 2015. The original authors should feel free to modify or downvote this commit if the spec should continue to be considered for implementation now or in the future. Change-Id: I6e243b34dbe82aab2f91887a8a8f46e44d10afbb
140 lines
2.4 KiB
ReStructuredText
140 lines
2.4 KiB
ReStructuredText
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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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Sort instances if possible inside an host aggregate
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===================================================
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.. note:: This spec was abandoned by efried on account of having been
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sitting in the backlog directory since 2015.
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https://blueprints.launchpad.net/nova/+spec/same-instances-scheduling
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Nova should allow sorting instances based on preferences without
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host aggregate speraration.
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Problem description
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===================
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As an operator, when you manage hundred or thousand nodes, instances will be
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automatically balanced though all nodes. There is no possibility to ask the
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infrastructure to group a kind of instances on the same hosts if possible.
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A kind of instance could be based on a specific image, a specific flavor.
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For this use case, host-aggregates are not used because this is not a strong
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constraint, this is a prefered situation.
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Use Cases
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----------
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Reduce the licence cost: Microsoft Windows licences are billed by host or by
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socket. The goal is to stack all Windows instances on the same hosts as much as
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possible.
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As much as possible means this is a best effort feature, if Nova can place
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this new Windows instance on a compute where other Windows are running, do
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it. If not, spawn it where you want or on a empty compute to identify it
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as `preferred widows compute` for future windows spawn.
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Proposed change
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===============
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Posting to get preliminary feedback on the scope of this spec.
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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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None
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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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None
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Work Items
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----------
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None
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Dependencies
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============
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None
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Testing
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=======
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None
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Documentation Impact
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====================
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None
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References
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==========
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None
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History
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=======
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None
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.. list-table:: Revisions
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:header-rows: 1
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* - Release Name
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- Description
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* - Liberty
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- Introduced
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* - Train
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- Abandoned
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