DebadityaHait opened a new pull request, #5458: URL: https://github.com/apache/datafusion-comet/pull/5458
## Which issue does this PR close? Closes #5455. ## Rationale for this change The tuning guide documents the transitionRevert mechanism but never mentions schema shape as the cost driver. As reported in #5455, columnar-to-row conversion becomes very expensive for wide or deeply nested schemas, where reverting the entire stage can be cheaper than paying repeated transitions. ## What changes are included in this PR? Extends the "Reducing Row/Columnar Conversion Overhead" section of the tuning guide with one short paragraph covering schema-shape-driven C2R cost and earlier-revert guidance using full config keys. ## How are these changes tested? Docs-only change; validated with a clean local Sphinx build of the site (no warnings for the changed file). Config keys and defaults match their definitions in `CometConf.scala`. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
