PostgreSQL 18 introduces Asynchronous I/O (AIO) to enhance database performance, particularly for read-heavy workloads in environments with higher storage latency, such as cloud platforms. Unlike the previous synchronous I/O model, which required blocking system calls for each data retrieval, AIO allows multiple read operations to be conducted concurrently, thus enabling overlap between I/O and computation for more efficient processing. This update utilizes an io_method configuration parameter that offers flexibility by supporting three methods: the default asynchronous worker method, synchronous I/O for maintaining previous behaviors, and io_uring for optimized performance on Linux systems. PostgreSQL 18's AIO is especially beneficial for large, read-intensive tasks, although write operations remain synchronous. The version also introduces the pg_aios system view for monitoring asynchronous I/O activities, providing users with deeper insights into database operations and performance.