virtual memory is very inconspicuous in Windows XP, Windows XP will automatically set it when installing, users do not even have to pay attention to 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 a "page file" or from the file name of the file.
Setting the hard disk
Optimizing the 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" and select "Properties -> Hardware" to open the device manager to find The hard disk currently in use, right click and select Properties. In the Policy page of the hard disk properties, turn on Enable Write Cache on Disk, as shown in Figure 1.
This option will activate the write cache of the hard disk, thus improving 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 your computer normally, it doesn't matter if you don't have a UPS. This function will not cause too much damage to the system.
Figure 1
2. Open Ultra MDA
In the device management, select "Basic /in the IDE ATA /ATAPI controller" Secondary IDE Controller, right-click and select Properties to open the Advanced Settings page. The most important setting item here is the "transport mode". Generally, you should select "DMA (if available)", as shown in Figure 2.
Figure 2
3. Configuration Recovery Options
Windows XP will save a snapshot of the memory when it encounters a fatal error during its operation. As a file for system debugging, this file is of little use to most ordinary users, but it will affect the performance of virtual memory. So it should be closed.
Right click on "My Computer", select "Properties -> Advanced", click "Settings" button under "Performance", select "Advanced" page in "Performance Options" . 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 data exchange between physical memory and virtual memory. speed. 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. However, if physical memory is tight, you should still leave the default options, as shown in Figure 3.
Figure 3
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.
The log function that comes with Windows XP can monitor the size of the page file normally used by the computer, so as to make the most accurate settings. The specific steps are as follows.
First, right click on "My Computer", select "Properties -> Advanced", click the "Settings" button under "Performance", then select the "Advanced" page, 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, go to "Control Panel -> Performance and Maintenance -> Management Tools", open "Performance", expand "Performance Logs and Warnings", select "Counter Log". Right-click on the right side of the window and select "New Log Settings", as shown in Figure 4.
FIG. 4
three, log easily set a name, such as "monitor virtual memory size", as shown in FIG 5.
Figure 5
Fourth, click the "Add Counter" button in the "General" page, as shown in Figure 6.
Figure 6
Select “Paging File” in “Performance Object”, then select “%Usage Peak” under “Select Counter from List” and right Select "_Total" from the side "Select a sample from the list". Finally click the "Add" and "Close" buttons, as shown in Figure 7.
Figure 7
V. Don't forget to remember the location and file name of the log file in the "Log File" page. We need to check this log later to judge Windows XP. How much virtual memory is used, in this case, the log files are stored in the D:\\Perflog directory, as shown in Figure 8.
Figure 8
Also set the "log file type" to "text file", which is easy to read, as shown in Figure 9.
Figure 9
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.
After opening this CVS file for a while, we can see the following items, as shown in Figure 10.
Figure 10
use this log file records this time in the page file, pay attention to where the unit 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
large, can be considered "initial size" page file and the "maximum value" is set to be equal, equal to the calculated step size. In this way, disk fragmentation will not occur due to page file transition expansion. The side effect is that the "maximum value" is set to be small. In case of accidental virtual memory overrun, the system may crash.
Setting Page File
Now go back to the "Virtual Memory" Settings dialog box and select the custom size and set the "Initial Size" and "Maximum" according to the above calculation results. ", as shown in Figure 11. Here we set the "initial size" to 91M and the "maximum" to 200M, which is safer.
Figure 11
Defragmenting page files
Windows XP runtime requires a lot of access to page files, if the page file is fragmented System performance will be severely affected and will shorten the life of the hard disk. So it is necessary for us to defragment the page files on a regular basis.
But do not forget, the page file is system critical files, Windows XP can not access run-time. 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, whose download address is
http://dl.pconline.com.cn/html/1/3/dlid=10173&dltypeid=1& Pn=0&.Html
http://www.sysinternals.com/ntw2k/freeware/pagedefrag.sHtml
, the volume is only 41KB.
After starting the System File Defragmenter, you can see the system files that can be sorted at the top of the window, including the page file, as shown in Figure 12.
Select "Defragment at Next Boot" or "Defragment Every Boot" at the bottom of the window. It is recommended to select the latter option.
Figure 12