Hey =)

I have a sidebar in my modeleditor, and there's a label "Memory usage". In the update function i do something like:

void cVmSidebar::onUpdate(){

static wstringstream wInfo;
wInfo.str("");
wInfo.clear();

wInfo<<(cCore::GetAllocatedMemory() / 1024)<<"Kb";
lpMemLabel->bSetWindowText(wInfo.str().c_str());

}

If i do so, allocated memory runs up and up and up... if i use something like:

void cVmSidebar::onUpdate(){

char buffer[10];
_itoa_s((cCore::GetAllocatedMemory()/1024), buffer, 10);

lpMemLabel->bSetWindowTextA(buffer);

}

it runs good, memory don't increases. Doesn't matter if i type "static wstringstream wInfo" or "wstringstream wInfo".
cCore::GetAllocatedMemory:

size_t cCore::GetAllocatedMemory(){

HANDLE process = GetCurrentProcess();
PROCESS_MEMORY_COUNTERS meminfo;

if (GetProcessMemoryInfo(process, &meminfo, sizeof(PROCESS_MEMORY_COUNTERS))){
return meminfo.WorkingSetSize;//PagefileUsage;
}

return 0;
}

Is this a memory leak? And... why is this happening?

Visual Studio 2010 Express, Version 10.30319.1 RTMRel (Latest)

Though it probably won't help in your case, using boost::lexical_cast rather than manually manipulating a stream can avoid memory leaks in some implementations; the boost library includes workarounds for things like the MSVC 2005 stream bug.

What is lpMemLabel->bSetWindowText function doing?
Does it make copy of string passed to it? Do you need to free it manually?

Looking at the working set isn't a very good way of detecting leaks. The working set is "a collection of those pages in its virtual address space that have been recently referenced". See http://msdn.microsoft.com/en-us/library/ms684891%28v=vs.85%29.aspx

You probably want to use the Debug Heap to look for leaks instead.

[quote=rip-off]The OP said: Doesn't matter if i type "static wstringstream wInfo" or "wstringstream wInfo".. It is unclear if this means promoting it to be a global or making it a non-static local. I hope the latter.[/quote]

>>I meant the following:
void xyz(){

static wstringstream wInfo;
wInfo.str("");
wInfo<<"Test"

}

void xyz_w(){

wstringstream wInfo;
wInfo<<"Test"

}

I'm not realy shure, that the "static" Keyword is good or not for performance, it was "test-wise".

[quote=MartinsM]What is lpMemLabel->bSetWindowText function doing?
Does it make copy of string passed to it? Do you need to free it manually? [/quote]

This is a function in the User-Interface part of my engine. It simply calls the MSDN function "SetWindowText" with the widgets HWND handle.

[quote=Adam_42]Looking at the working set isn't a very good way of detecting leaks. [...] You probably want to use the Debug Heap to look for leaks instead. [/quote]

It was not my goal to display the debug heap or else, i simply like to show the current size of allocated memory by my process, like in the taskmanager. I searched google for this and found some posts, describing the usage of PROCESS_MEMORY_COUNTERS. Is there a better way to display the allocated memory ?

If i look in the taskmanager, the used memory for my process increases too. Only if i comment "wstringstream wInfo" out, the memory usage stays constant...