Windows XP is wasting your money?

For the role of CPU L2 Cache, I think everyone must know more or less, even if you don't fully understand the truth, you can at least judge the importance of the difference between Pentium 4 and Celeron - 256KB L2 cache The Celeron D 2.4GHz is nearly half the price of the Pentium 4 2.4C with 512KB L2 cache. If at this time someone said that the Windows XP operating system did not make full use of the CPU's L2 cache, what would you think? This is simply wasting the user's investment!

In fact, there is a widespread argument is that Windows XP is not optimized for the CPU, the reason is that it is not turned on by default and secondary cache CPU. If you open the Registry Editor, find "HKEY_LOCAL_MacHINE\\SYSTEM\\ CurrentControlSet\\Control\\Session Manager\\Memory Management", where you can see an item named "SecondLevelDataCache" whose default value is "0". Obviously, "SecondLevelDataCache" means the secondary data cache. Since it is set to "0", it is closed the secondary cache.



It is based on the above assertion that the technique of optimizing the secondary cache appears, that is, the value of "SecondLevelDataCache" is set to the secondary cache capacity of the CPU (in KB). The optimization software also includes settings for optimizing the CPU's L2 cache, such as "Super Rabbit Magic Settings", "WindowsOptimization Master
" and PcMedik. How effective is this optimization? Still let the facts speak better, please see our comparative test.

From the test results, modify the value of "SecondLevel DataCache" has no effect on the test results, which is why? In fact, as you can see from Microsoft's Knowledge Base article (http://support.microsoft.com/default.ASPx?scid=kb
;en-us;183063), starting with Windows NT4, The default setting of "SecondLevelData Cache" is already "0". This article points out that when "SecondLevelDataCache" is "0", the system will try to obtain the L2 cache capacity through the Hardware Abstraction Layer (HAL). Even if the hardware abstraction layer cannot obtain the L2 cache capacity, the system defaults. Set the secondary cache to 256KB instead of completely turning off the secondary cache. In another Windows 2000 Knowledge Base article (http://support.microsoft.com/default.ASPx?scid=kb
;en-us;228766), the user is explicitly told that some Third-party data claims that modifying "SecondLevelDataCache" can optimize system performance, which is not true. Windows XP and Windows NT4/2000 are both NT kernels, so they have some inheritance in design. Although these two knowledge base articles are not directly proposed for Windows XP, you can see this problem for a long time, Windows NT The series of operating systems have taken this issue into consideration at the beginning.

can be concluded from the interpretation of the test results and the actual Microsoft Knowledge Base article, the so-called Windows system is not optimized for CPU is wrong, although manually modify the "SecondLevelDataCache" did not bring any negative Impact, but this "optimization" is definitely more than one move.


Test Platform:
CPU Pentium 4 2.8E
Motherboard MSI 865PE Neo2
Memory Kingston DDR400 (256MB×2)
Hard Disk Maxtor Plus 9 120GB (SATA) < BR> graphics ELSA shadow leizhe FX534DV
operating system Windows XP Pro + SP1

SecondLevelDataCache Super Pi 209 Wan bit test
0 110
1024 110 Miao Miao Miao
512 110 < BR> 256 110 seconds
128 110 seconds
64 110 seconds
32 110 seconds
16 110 seconds
8 110 seconds