Determining the Amount of Installed Memory

Start your monitoring efforts knowing that you have at least the minimum amount of memory required to run Windows 2000. These requirements are as follows:

• Microsoft® Windows® 2000 Professional: 32 megabytes (MB)

• Microsoft® Windows® 2000 Server: 64 MB

The memory recommendation for Windows 2000 Professional is based on a typical desktop configuration including a business productivity application, such as a word processor or a spreadsheet program, an e-mail application, and a Web browser. The memory recommended for Windows 2000 Server is based on either a dedicated or a multiuse server with a low load, such as a small file-sharing and Web service configuration for a small office. If you are using a database management system such as Microsoft® SQL Server ™ or a messaging server such as Microsoft® Exchange, consult the documentation for those products to determine the memory recommended for running them on Windows 2000 Server.

There are a few different ways to determine the amount of memory on your computer. You can find the amount of physical memory installed on your system by clicking the Performance tab in Task Manager. Or you can find the amount of available RAM by double-clicking System in Control Panel and then clicking the General tab.

Note

You can see the memory configuration on local or remote systems using System Information. For more information, see Windows 2000 Server Help.

The operating system distinguishes memory usage by applications and services depending on whether the usage involves the paged or the nonpaged pool. The paged pool contains memory for objects used by applications and services that can be paged to disk; objects in the nonpaged pool cannot be paged to disk. The operating system determines the size of each pool based on the amount of physical memory present. Memory pool usage can be an important factor in evaluating memory usage by your applications. For more information, see "Investigating User-Mode Memory Leaks" and "Investigating Kernel-Mode Memory Leaks" later in this chapter.

The file system cache, which is a subset of physical memory used for fast access to data, and the disk paging file , which supports virtual memory , influence the amount of memory used by the operating system and applications. (The disk paging file, also called a swap file, is a file on the hard disk that serves as temporary, virtual memory storage for code and data.) Virtual memory is the space on the hard disk that Windows 2000 uses as memory. For purposes of monitoring, the most important types of virtual memory are committed memory that the system sets aside for a process in the paging file and available memory that is not in use by a process. (Another type of memory managed by Windows 2000 is reserved memory, which the system sets aside for a process but which might not be entirely used.) The following sections describe the influence of the cache and the paging file on performance and explain how best to adjust these for optimal memory usage.