Edit - Stack Overflow

You are not logged in. Your edit will be placed in a queue until it is peer reviewed.

We welcome edits that make the post easier to understand and more valuable for readers. Because community members review edits, please try to make the post substantially better than how you found it, for example, by fixing grammar or adding additional resources and hyperlinks.

Required fields*

Rev

Required fields*

How to get current CPU and RAM usage in C++?

is it possible, in C++, to get the current RAM and CPU usage? Is there a platform-indepentent function call?

Answer*

There is not a platform independent function for this that I know of. IF you plan to target multiple versions of Windows be aware that the implementation differs across some versions. I hit this problem when testing an app under NT 3.51 for instance... (archaic, I know).

Here is some code I used for the memory side of things. This doesn't work across platforms other than windows, and will just return 0 when compiled without the WIN32 define:

EDIT: I forgot to mention, this code divides and rounds down to the nearest MB, hence the >> 20 all over the place.

// 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;
    }

Edit Summary*

Cancel

Add a comment |

Correct minor typos or mistakes
Clarify meaning without changing it
Add related resources or links
Always respect the author’s intent
Don’t use edits to reply to the author

create code fences with backticks ` or tildes ~
```
like so
```
add language identifier to highlight code
```python
def function(foo):
print(foo)
```
put returns between paragraphs
for linebreak add 2 spaces at end
_italic_ or **bold**
indent code by 4 spaces
backtick escapes `like _so_`
quote by placing > at start of line
to make links (use https whenever possible)

<https://example.com>

[example](https://example.com)

<a href="https://example.com">example</a>

formatting help »
answering help »

Collectives™ on Stack Overflow

How to get current CPU and RAM usage in C++?

Answer*