hhhizzz commented on issue #8846: URL: https://github.com/apache/arrow-rs/issues/8846#issuecomment-5235308225
Related data point from a completed selected-decoding investigation ([report](https://github.com/hhhizzz/arrow-rs/blob/exp/v21-rle-selected-fill-20260807/experiments/shape-aware-selected-decoding/README.md)): when I pushed a row selection down into dictionary decoding, selector morphology alone did not predict query-level benefit. Two further things had to hold — the optimization had to be *reachable* under a correctness-preserving admission rule (0/99 TPC-DS and 4/42 ClickBench queries qualified), and the affected work had to be a meaningful share of query CPU (3.0–3.6% of suite runtime for the covered queries). This seems consistent with the multi-level adaptivity direction in this issue: shape is a necessary input to the decision but not a sufficient one. -- 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]
