Asynchronous I/O Support in Linux 2.5

Abstract

This paper describes the Asynchronous I/O (AIO) support in the Linux® 2.5 kernel, additional functionality available as patchsets, and plans for further improvements. More specifically, the following topics are treated in some depth: • Asynchronous filesystem I/O • Asynchronous direct I/O • Asynchronous vector I/O As of Linux 2.5, AIO falls into the common mainline path underlying all I/O operations, whether synchronous or asynchronous. The implications of this, and other significant ways in which the design for AIO in 2.5 differs from the patches that existed for 2.4, are explored as part of the discussion.