f53c30d90b
TrivialFix: "automaticly" should be "automatically" "instnaces" should be "instances" "verison" should be "version" Change-Id: If470b65277718a4c6d1c56b4d215b565babe67d0
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2.2 KiB
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135 lines
2.2 KiB
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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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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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