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JIRA:

Released: (targeting hopefully 9.0.0 ?)

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Chris Hostetter suggested that in the light of Solr being more and more often used in containerized environments (Docker, Kubernetes), which already provide their own support for up- / down-scaling, the built-in V2 framework in Solr should offer only a bare minimum to support the most common cases (eg. equal placement of replicas across nodes, by # of cores & freedisk). The scope fo the Solr autoscaling would be to adequately support basic needs of standalone (non-containerized) Solr clusters. All other more sophisticated scenarios should be left out, but Solr should provide API hooks to make it easier for external frameworks to react and optimize the layout and resolve resource constraints (eg. too many / too few nodes for the # of replicas).

Clean-cut pluggable APIs

Concerns were raised that the current autoscaling implementation is too intrusive, regardless of its strengths and deficiencies. Ilan Ginzburg, Noble Paul and Andrzej Bialeckiare investigating what a minimal set of APIs could look like. Some others proposed a spike to investigate how much effort would be to remove the autoscaling completely, clean up the existing APIs and add it again as a plugin (using the Plugins framework).

Requirements for the V2 policy engine

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