如何申请操作系统的物理内存？

[lance_123]

一般我们在应用程序中用new,malloc函数，都是申请虚拟内存。
我想直接能够申请物理内存。
查看了一些资料，有人说用AllocateUserPhysicalPages这个函数，但是我在VC6下怎么也运行不起来了。换了在VS2005下也不行。。。
请问有人写过这样的程序吗？帮助解决一下。谢谢。

[oyljerry]

http://msdn.microsoft.com/en-us/library/aa366528(VS.85).aspx

The AllocateUserPhysicalPages function is used to allocate physical memory that can later be mapped within the virtual address space of the process. The SeLockMemoryPrivilege privilege must be enabled in the caller's token or the function will fail with ERROR_PRIVILEGE_NOT_HELD. For more information, see Privilege Constants.

Memory allocated by this function must be physically present in the system. After the memory is allocated, it is locked down and unavailable to the rest of the virtual memory management system.

Physical pages cannot be simultaneously mapped at more than one virtual address.

Physical pages can reside at any physical address. You should make no assumptions about the contiguity of the physical pages.

To compile an application that uses this function, define the _WIN32_WINNT macro as 0x0500 or later. For more information, see Using the Windows Headers.

[lance_123]

加了#define _WIN32_WINNT 0x0501
这个也不行。。。
环境是VC6
: error C2065: 'AllocateUserPhysicalPages' : undeclared identifier
报这个错误。。

[lance_123]

#define _WIN32_WINNT 0x0500
也试过了，就是不行。

[biweilun]

我觉得好奇怪，干吗非要物理内存不可呢。

实在要，请看这个牛帖：http://bbs.et8.net/bbs/archive/index.php/t-488600.html

[lance_123]

看过了，因为打算开发一个数据库产品。而这样需要对内存有很好的管理。第一步就是想把数据全部放在物理内存上去处理，而不需要让操作系统去置换。从而降低性能。