如何在C++中获得当前的CPU和RAM使用率？

Question

在C++中,是否有可能获得当前的RAM和CPU使用率？是否存在平台无关的函数调用？

Answer 1

遗憾的是,这些东西严重依赖底层操作系统,所以没有平台无关的调用.(也许有一些包装器框架,但我不知道.)

在Linux上,您可以查看getrusage()函数调用,在Windows上,您可以使用GetProcessMemoryInfo()进行RAM使用.还要看一下Windows 的Process Status API中的其他功能.

Answer 2

我知道没有与平台无关的功能.如果您计划针对多个版本的Windows,请注意某些版本的实现会有所不同.我在NT 3.51下测试应用程序时遇到了这个问题......(过时,我知道).

这是我用于内存方面的一些代码.这不适用于除Windows以外的平台,并且在没有WIN32定义的情况下编译时将返回0:

编辑:我忘了提,这个代码分为并向下舍入到最近的MB,因此>> 20到处都是.

// get memory info...
int getTotalRAM()
{
    int ret = 0;
#ifdef WIN32
    DWORD v = GetVersion();
    DWORD major =  (DWORD)(LOBYTE(LOWORD(v)));
    DWORD minor =  (DWORD)(HIBYTE(LOWORD(v)));
    DWORD build;
    if (v < 0x80000000) build = (DWORD)(HIWORD(v));
    else build = 0;

    // because compiler static links the function...
    BOOL (__stdcall*GMSEx)(LPMEMORYSTATUSEX) = 0;

    HINSTANCE hIL = LoadLibrary(L"kernel32.dll");
    GMSEx = (BOOL(__stdcall*)(LPMEMORYSTATUSEX))GetProcAddress(hIL, "GlobalMemoryStatusEx");

    if(GMSEx)
    {
        MEMORYSTATUSEX m;
        m.dwLength = sizeof(m);
        if(GMSEx(&m))
        {
            ret = (int)(m.ullTotalPhys>>20);
        }
    }
    else
    {
        MEMORYSTATUS m;
        m.dwLength = sizeof(m);
        GlobalMemoryStatus(&m);
        ret = (int)(m.dwTotalPhys>>20);
    }
#endif
    return ret;
}

int getAvailRAM()
{
    int ret = 0;
#ifdef WIN32
    DWORD v = GetVersion();
    DWORD major =  (DWORD)(LOBYTE(LOWORD(v)));
    DWORD minor =  (DWORD)(HIBYTE(LOWORD(v)));
    DWORD build;
    if (v < 0x80000000) build = (DWORD)(HIWORD(v));
    else build = 0;

    // because compiler static links the function...
    BOOL (__stdcall*GMSEx)(LPMEMORYSTATUSEX) = 0;

    HINSTANCE hIL = LoadLibrary(L"kernel32.dll");
    GMSEx = (BOOL(__stdcall*)(LPMEMORYSTATUSEX))GetProcAddress(hIL, "GlobalMemoryStatusEx");

    if(GMSEx)
    {
        MEMORYSTATUSEX m;
        m.dwLength = sizeof(m);
        if(GMSEx(&m))
        {
            ret = (int)(m.ullAvailPhys>>20);
        }
    }
    else
    {
        MEMORYSTATUS m;
        m.dwLength = sizeof(m);
        GlobalMemoryStatus(&m);
        ret = (int)(m.dwAvailPhys>>20);
    }
#endif
    return ret;
}

int getTotalMemory()
{
    int ret = 0;
#ifdef WIN32
    DWORD v = GetVersion();
    DWORD major =  (DWORD)(LOBYTE(LOWORD(v)));
    DWORD minor =  (DWORD)(HIBYTE(LOWORD(v)));
    DWORD build;
    if (v < 0x80000000) build = (DWORD)(HIWORD(v));
    else build = 0;

    // because compiler static links the function...
    BOOL (__stdcall*GMSEx)(LPMEMORYSTATUSEX) = 0;

    HINSTANCE hIL = LoadLibrary(L"kernel32.dll");
    GMSEx = (BOOL(__stdcall*)(LPMEMORYSTATUSEX))GetProcAddress(hIL, "GlobalMemoryStatusEx");

    if(GMSEx)
    {
        MEMORYSTATUSEX m;
        m.dwLength = sizeof(m);
        if(GMSEx(&m))
        {
            ret = (int)(m.ullTotalPhys>>20) + (int)(m.ullTotalVirtual>>20);
        }
    }
    else
    {
        MEMORYSTATUS m;
        m.dwLength = sizeof(m);
        GlobalMemoryStatus(&m);
        ret = (int)(m.dwTotalPhys>>20) + (int)(m.dwTotalVirtual>>20);
    }
#endif
    return ret;
}

int getAvailMemory()
{
    int ret = 0;
#ifdef WIN32
    DWORD v = GetVersion();
    DWORD major =  (DWORD)(LOBYTE(LOWORD(v)));
    DWORD minor =  (DWORD)(HIBYTE(LOWORD(v)));
    DWORD build;
    if (v < 0x80000000) build = (DWORD)(HIWORD(v));
    else build = 0;

    // because compiler static links the function...
    BOOL (__stdcall*GMSEx)(LPMEMORYSTATUSEX) = 0;

    HINSTANCE hIL = LoadLibrary(L"kernel32.dll");
    GMSEx = (BOOL(__stdcall*)(LPMEMORYSTATUSEX))GetProcAddress(hIL, "GlobalMemoryStatusEx");

    if(GMSEx)
    {
        MEMORYSTATUSEX m;
        m.dwLength = sizeof(m);
        if(GMSEx(&m))
        {
            ret = (int)(m.ullAvailPhys>>20) + (int)(m.ullAvailVirtual>>20);
        }
    }
    else
    {
        MEMORYSTATUS m;
        m.dwLength = sizeof(m);
        GlobalMemoryStatus(&m);
        ret = (int)(m.dwAvailPhys>>20) + (int)(m.dwAvailVirtual>>20);
    }
#endif
    return ret;
}

Answer 3

有一个开源库可以跨多个平台提供这些(以及更多系统信息):SIGAR API

我已经在相当大的项目中使用它并且它工作正常(除了OS X上的某些极端情况等)

Answer 4

不,没有,不在标准中.

如果您确实需要此信息,则必须编写特定于平台的#ifdefs或链接到提供它的库.