Windows XP virtual memory knowledge

Windows XP virtual memory knowledge

Virtual memory is very inconspicuous in Windows XP, Windows XP will automatically set it when installing, users do not even care about it This file. However, virtual memory as a supplement and extension of physical memory plays a decisive role in the stable operation of Windows XP. If it is not well set, it will affect the overall performance of the computer.

What is virtual memory?

Virtual memory is Windows XP as part of the hard disk space used as memory. Virtual memory is essential even if physical memory is large. Virtual memory on the hard disk is actually a huge file, the file name is PageFile.Sys, usually can not be seen. The resource manager's protection of system files must be turned off to see this file. Virtual memory is sometimes referred to as "page file"; it is from the file name of this file.

Setting up the hard disk

Optimizing virtual memory, why do you want to set the hard disk? This is because virtual memory files (also known as page files) are stored on the hard disk, and improving the performance of the hard disk can also improve the performance of the memory to some extent.

1. Enable Disk Write Cache

Right click on “My Computer> Select “Properties->Hardware”, open Device Manager and find the current Use the hard disk, right click and select Properties. In the <quo;Policy" page of the hard disk properties, open “Enable write caching on disk”. This option will activate the hard disk's write cache, which will increase the read and write speed of the hard disk. However, be aware that after this feature is turned on, if the computer suddenly loses power, it may result in irreparable data loss. It is therefore best to turn this feature back on with a UPS. Of course, if you don't do any important data processing work when you use the computer normally, it doesn't matter if there is no UPS. This function will not cause too much loss to the system

2. Open Ultra MDA

In Device Management, select "Basic/Secondary IDE Controller" in the IDE ATA/ATAPI Controller, right-click and select "Properties" to open the "Advanced Settings" page. The most important setting item here is “transfer mode”, generally should select “DMA (if available)”.

3. Configuring recovery options

When a fatal error occurs during Windows XP, a snapshot of the memory is saved as a file for system debugging, for most normal users. In other words, this file is of no use, but it will affect the performance of virtual memory. So it should be closed.

Right click on “My Computer", select “Properties->Advanced", under "Performance", click “Set” button in “ In the Performance Options & rdquo; select “Advanced& rdquo; page. There is a “memory usage” option. If you set it to “system cache”, Windows XP will use about 4MB of physical memory as the cache for reading and writing the hard disk, which can greatly improve the physical memory and virtual memory. The speed of data exchange between. By default, this option is turned off. If your computer has sufficient physical memory, such as 256M or more, it is best to turn this option on. But if physical memory is tight, you should still leave the default options.

Page File Settings

Page File Size Calculation

The page file size varies from computer to computer. Regarding the page file size setting, there are two widely spread "Formulas", "Physical Memory X2.5" or "Physical Memory X1.5". These two calculation methods are simple, but not applicable to all computers. The most accurate way to set the page file size is to look at the page file size that the computer actually uses in normal operation.

With the built-in logging function of Windows XP, you can monitor the size of the page file normally used by your computer for the most accurate settings. The steps are as follows.

First, right-click on "My Computer" and select "“Properties->Advanced", click on "Performance>;>Settings> Select the “Advanced" page and click the “Change” button under "Virtual Memory". Select “Custom Size” and set both “start size” and “maximum" to 300M, which is just a temporary setting. Restart the computer after the setup is complete for the settings to take effect.

Second, enter "Control Panel -> Performance and Maintenance -> Management Tools", open "performance", expand "performance logs and warnings", select “ counter log & rdquo ; Right-click on the right side of the window and select “New Log Settings”;

Three, just set a log name, such as “Monitor Virtual Memory Size”;

Four “General” Click the "Add Counter" button;

Select “Paging File” in “Performance Object", and then select “Select Register from List” Select “%Usage Peak” below and select “_Total” from the Select example from the list on the right. Finally click on the “Add” and “Close” buttons.

Five, don't forget to remember the log file storage location and file name in the log file, we need to check this log to determine how much virtual memory Windows XP usually uses. In the example, the log file is stored in the D:\\Perflog directory; in addition, the “log file type” is “text file", which is easy to read. At this point you can see that the icon in front of the newly created log entry has turned green, indicating that the log system is already monitoring virtual memory. If the icon is still red, you should right-click and select “Start” to start the log.

This log file records the usage of the page file during this period of time. Note that the unit here is %, not MB. With a simple calculation, we can get the minimum size of the page file, the formula is "page file size X percentage". For example, in this example, the maximum usage ratio of virtual memory is 31%, 300MBX31%=93MB, which is the minimum value of virtual memory (note that 300MB is the temporary value of the previous setting).

If the physical memory is large, consider setting the page file's “start size” and “maximum" to equal, equal to the size calculated in the previous step. In this way, disk fragmentation will not occur due to page file transition expansion. The side effect is that the "maximum value" is set smaller, and in case of occasional virtual memory overrun, it may cause the system to crash.

Set Page File

Now go back to the setting dialog box of “Virtual Memory” and select the custom size and set the “Initial Size” and “Order” respectively according to the above calculation results. Maximum value & rdquo;. Here we set the "initial size" to 91M, and set the "maximum" to 200M, which is safer.

Defragmenting Page Files

Windows XP requires a lot of access to page files when running. If the page files are fragmented, system performance will be seriously affected and the life of the hard disk will be shortened. So it is necessary for us to defragment the page files on a regular basis.

But don't forget, the page file is a system key file that Windows XP cannot access when it is running. So defragmenting it is not an easy task. We have two options to choose from. One is to install Windows dual system, and then start another Windows to defragment the partition where Windows XP is located. The second is to use specialized tool software, such as System File Defragmenter.