perf(arrow/csv): reserve record builders for chunked reads - #1198
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Summary
Benchmark
On an Apple M1 Pro,
BenchmarkRead/rows=1000_cols=100_chunks=10improved locally from a median of about 36.4 ms to 25.6 ms.The gain is chunk-size dependent. Very small batches are already close to the builders’ minimum capacity.
Tests
PARQUET_TEST_DATA=... go test ./arrow/csv -run ^Test\n*PARQUET_TEST_DATA=... go test -race ./arrow/csv -run ^Test\n* Full package test run passed with the local Parquet test data checkout, excluding the CSV example that needs a separate Arrow CSV fixture.