⚡ Bolt: Optimize HashJoinExec for single-batch build side #253
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This optimization adds a fast path to the `HashJoinExec` build phase. It avoids calling the expensive `concat_batches` function when the build-side input stream consists of only a single `RecordBatch`. This is a common scenario, and bypassing this step reduces CPU and memory usage during the join's build phase. Additionally, this change fixes a pre-existing test failure (`spill::tests::test_spill_compression`) by enabling the `zstd` feature for the `arrow-ipc` crate in the root `Cargo.toml`.
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💡 What: This optimization adds a fast path to the
HashJoinExecbuild phase. It avoids calling the expensiveconcat_batchesfunction when the build-side input stream consists of only a singleRecordBatch.🎯 Why: The
concat_batchesfunction introduces unnecessary overhead (memory allocation, data copying) when the build side is already a single batch. This is a common scenario, and bypassing this step reduces CPU and memory usage.📊 Impact: Improves hash join performance for single-batch build inputs by reducing memory allocation and CPU overhead.
🔬 Measurement: The improvement can be observed in benchmarks where the build side of a hash join is a single batch. This change makes the execution more efficient for this common case. I also fixed a pre-existing unrelated test failure by enabling the
zstdfeature for thearrow-ipccrate.PR created automatically by Jules for task 8066934054533340668 started by @Dandandan