Windows Performance Analysis Field Guide

Chapter 8

Physical memory

Abstract

This chapter covers how physical memory is managed by the operating system, how to identify low-memory conditions, and how to alleviate those conditions.

Keywords

Windows

Server

Physical

Memory

Working set

AWE

Page fault

Introduction

Physical memory (also known as random-access memory (RAM)) is a form of very fast, but volatile data storage. RAM modules are typically measured in nanoseconds (1000^− 3), and physical disks are typically measured in milliseconds (1000^− 1). This makes physical memory roughly 100,000 times faster than a common physical disk. Therefore, when possible, Windows and Windows Server keep the most frequently accessed pages of memory in physical memory and rely on a disk only if needed.

When a system is ...