Programmer1970

Sep 26, 2024 · Databases

How MySQL’s Multi-Range Read (MRR) Turns Random I/O into Sequential I/O

The article explains MySQL’s Multi-Range Read (MRR) optimization, detailing how it scans secondary indexes, buffers and sorts primary keys, leverages disk pre‑read and cache locality to convert random I/O into sequential I/O, and shows configuration, monitoring methods, and a concrete orders‑table example.