Asynchronous I/O in DuckDB: Work, Thread, Work
Summary
DuckDB introduces asynchronous I/O for Parquet and CSV, enabling read-ahead and separate I/O threads to overlap data transfer with decoding. Benchmarks on remote data lakes (S3/EC2) show substantial performance gains over synchronous I/O, with plans to add async support for more formats and potential io_uring integration. This article explains the implementation approach and the impact on data-lake workloads.