Performance Tuning for Linux® Servers

Chapter Ten. I/O Subsystems—Performance Implications

By Dominique Heger

Introduction

In many circumstances, the perceived speed of computing is increasingly dependent on the performance of the I/O subsystem, underscoring the necessity for high-performance I/O solutions. Unfortunately, many operating systems provide inadequate support for applications, leading to poor performance and increased hardware cost of server systems.

One source of the problem is the lack of integration among the various I/O subsystems and the applications. Each I/O subsystem utilizes its own buffering or caching mechanism, and applications generally maintain their own I/O buffers. This approach leads to performance-degrading anomalies such as repeated data copying and multiple ...