alamb opened a new pull request, #24150: URL: https://github.com/apache/datafusion/pull/24150
## Which issue does this PR close? - Part of #24149 ## Rationale for this change Profiling ClickBench Q24 in #24149 showed almost 10% of query time spent cloning `ParquetMetaData`. When a page pruning predicate exists, the opener tries to load the page index by deep-cloning the `ParquetMetaData` (the `Arc` is also held by the metadata cache, so `Arc::try_unwrap` always fails) and handing it to `ParquetMetaDataReader`. For files that have no page index at all (such as the ClickBench `hits` files), the reader then discovers there is nothing to load and the clone was pure waste — paid on every file open. The footer metadata already records the column/offset index locations (`ColumnChunkMetaData::column_index_offset()` / `offset_index_offset()`) even when the index itself has not been read, so we can determine that a load can never succeed without any I/O or cloning. ## What changes are included in this PR? - Add `file_has_page_index` which checks the column chunk metadata for recorded column/offset index offsets - Only attempt to load the page index (which requires cloning the `ParquetMetaData`) when the file actually has one ## Are these changes tested? New unit test `test_file_has_page_index`, plus existing coverage: page index behavior is exercised by the existing `datasource-parquet` unit tests and the parquet sqllogictests. Benchmark results (ClickBench Q24) to follow in the comments. ## Are there any user-facing changes? No, this is a performance optimization only. -- 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]
