Rich-T-kid opened a new pull request, #11162: URL: https://github.com/apache/arrow-rs/pull/11162
# Which issue does this PR close? <!-- We generally require a GitHub issue to be filed for all bug fixes and enhancements and this helps us generate change logs for our releases. You can link an issue to this PR using the GitHub syntax. --> - Closes #10804.. # Rationale for this change set_write_row_group_number_distinct_values was added in #10654 with no benchmarks. This PR adds them so the cost of NDV tracking is visible and regressions are catchable going forward. <!-- Why are you proposing this change? If this is already explained clearly in the issue then this section is not needed. Explaining clearly why changes are proposed helps reviewers understand your changes and offer better suggestions for fixes. --> # What changes are included in this PR? Adds a `bench_ndv` benchmark group to `parquet/benches/arrow_writer.rs` covering the data types that NDV tracking supports: Int32 (primitive), Boolean, Utf8, LargeBinary, and FixedSizeBinary(16). Each group writes 10 batches of 65,536 rows through a single ArrowWriter with `set_write_row_group_number_distinct_values(true)`. Two cardinality shapes are exercised per type: low (100 distinct values, cycling) and high (all unique, random), since hash-set behaviour differs meaningfully between the two. <!-- There is no need to duplicate the description in the issue here but it is sometimes worth providing a summary of the individual changes in this PR. --> # Are these changes tested? n/a <!-- We typically require tests for all PRs in order to: 1. Prevent the code from being accidentally broken by subsequent changes 2. Serve as another way to document the expected behavior of the code If tests are not included in your PR, please explain why (for example, are they covered by existing tests)? If this PR claims a performance improvement, please include evidence such as benchmark results. --> # Are there any user-facing changes? n/a cargo bench --bench arrow_writer --features arrow/test_utils -- "ndv/" <!-- If there are user-facing changes then we may require documentation to be updated before approving the PR. If there are any breaking changes to public APIs, please call them out. --> -- 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]
