Windows系统缓存和大型文件

我的windows系统缓存有问题。

int main(int argc, char* argv[])
{
    HANDLE file_ = INVALID_HANDLE_VALUE;
    file_ = CreateFile(
                            "test_file.txt",
                            GENERIC_WRITE, 
                            FILE_SHARE_READ, 
                            0, 
                            OPEN_ALWAYS, 
                            FILE_FLAG_SEQUENTIAL_SCAN, 
                            NULL
                            );
    if (file_ == INVALID_HANDLE_VALUE || file_ == NULL)
    {
        std::cout << "CreateFile error " << GetLastError() << std::endl;
        return GetLastError();
    }
    int counter = 0;
    DWORD io_bytes = 0;
    while(true)
    {
        char buffer[0x1000];
        int len = _snprintf_s(buffer, 0x1000, 0xffff, "test message %d\r\n", counter);
        counter++;
        if ( !WriteFile(file_, buffer, len, &io_bytes, NULL) )
        {
            std::cout << "WriteFile error " << GetLastError() << std::endl;
            return GetLastError();
        }
        if (counter > 10000000)
        {
            system("pause");
            return 0;
        }
    }
}