How to Optimizing memory

Like many other operating systems, Windows XP Professional addresses memory from both a physical and virtual level. Physical memory is the amount of random access memory in your workstation, whereas virtual memory is the amount of memory than can be written to your system's hard disk. Integral to the development of the Windows NT operating system, Microsoft has always relied on virtual memory for increasing baseline performance.
The virtual memory paging file, called PAGEFILE.SYS, can be modified in size through a series of steps shown here. For the best possible performance, it's best to have a virtual memory partition on each disk drive. When defining the size of the PAGEFILE.SYS file for each disk drive, it's best to set this file's size at double the physical memory in the system. To optimize physical and virtual memory, follow these series of steps:
Double-click on the System icon in the Control Panel. The System Properties dialog box appears.
Click once on the Advanced page tab at the top of the System Properties dialog box. Figure 1 shows this specific page of the dialog box.
Figure 1 Configuring your Windows XP system for higher performance using the Advanced tab of the System Properties dialog box.
In the Performance segment of the Advanced page (the first entry on the top of the page), click once on Settings. The Performance Options dialog box appears, as shown in Figure 2.
Figure 2: Using the Performance Options dialog box, you can define the virtual memory paging file size.
Click once on the Advanced tab of the Performance Options dialog box. Figure 3 shows the contents of the Advanced tab: Processor scheduling, Memory usage, and Virtual memory.
Figure 3 The Advanced page of the Performance Options dialog box gives you control over setting virtual memory sizing
Notice that at the bottom of the page there is an entry for defining the virtual paging size for your Windows XP system. Click once on the Change button. The Virtual Memory dialog box appears, as shown in Figure 4.
Figure 4 Using the options in the Virtual Memory dialog box to define paging file size.
The purpose of this dialog box is to define the size of the paging file your system will use. You can, for example, toggle Windows XP Professional to not provide any paging file by selecting the No paging file option (although it will save on disk space, it will inhibit your system's overall performance). The best selection in this area is to select System managed size because Windows XP will calculate the size of the virtual paging file for you. After you select the option you want for this specific option, click once on Set in the Paging file size for selected drive section.
Click once on OK to close the Virtual Memory dialog box; then, select OK in the two other dialog boxes until the main desktop is again shown.
Reboot your system, and PAGEFILE.SYS will be created. You'll notice that the file appears in the partition as defined in the Virtual Memory dialog box. Your system should now run more efficiently, especially when several concurrent applications are in use at the same time.

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