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• OpenTelemetry for Metrics instead of DropWizard.  Attribute based; supports pushing metrics thus avoiding Prometheus translation
• Segment level filterCache, augmenting or replacing current global strategy
• Limit concurrent HTTP requests / threads to a sane value, not 10k in jetty.xml.  Not trivial; don't want to dead-lock at scale.  Related (but not the same) issue:

  Jira
  server ASF JIRA serverId 5aa69414-a9e9-3523-82ec-879b028fb15b key SOLR-7344

• schema.xml:  Default field types (esp. for non-text) so users needn't define the basics.
• Transition from "javabin" to CBOR via Jackson.  Status of CBOR –

  Jira
  server ASF JIRA serverId 5aa69414-a9e9-3523-82ec-879b028fb15b key SOLR-17510

• Load built-in and other plugins via Java java.util.ServiceLoader / SPI, just like how Lucene components are loaded.
• SolrJ/Solr Backwards-compatibility tests.  Should work via Docker/TestContainers.  See SOLR-17653
• Cloud/remote storage via Java NIO FileSystem –

  Jira
  server ASF JIRA serverId 5aa69414-a9e9-3523-82ec-879b028fb15b key SOLR-17646

Roadmap

Started but not finished

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