I am rendering a large number of objects for a simulation. Each object has instance data and the size of the instance data * number of objects is greater than 4GB. 

CreateCommittedResource is giving me: E_OUTOFMEMORY Ran out of memory. 

My PC has 128GB (only 8% ish used prior to testing this), I am running the DirectX app as x64. <Creating a CPU sided resource so GPU ram doesn't matter here, but using Titan X cards if that's a question>

Simplified code test that recreates the issue (inserted the code into Microsofts D3D12HelloWorld): 

unsigned long long int siz = pow(2, 32) + 1024;

D3D12_FEATURE_DATA_D3D12_OPTIONS options; //MaxGPUVirtualAddressBitsPerResource = 40
m_device->CheckFeatureSupport(D3D12_FEATURE_D3D12_OPTIONS, &options, sizeof(options));

HRESULT oops = m_device->CreateCommittedResource(
	&CD3DX12_HEAP_PROPERTIES(D3D12_HEAP_TYPE_UPLOAD),
	D3D12_HEAP_FLAG_NONE,
	&CD3DX12_RESOURCE_DESC::Buffer(siz),
	D3D12_RESOURCE_STATE_GENERIC_READ,
	nullptr,
	IID_PPV_ARGS(&m_vertexBuffer));

if (oops != S_OK)
{
	printf("Uh Oh");
}

I tried enabling "above 4G" in the bios, which didn't do anything. I also tested using malloc to allocate a > 4G array, that worked in the app without issue. 

Are there more options or build setup that needs to be done? (Using Visual Studio 2015)

*Other approaches to solving this are welcome too. I thought about splitting up the set of items to render into a couple of sets with a size < 4G each but would rather have one set of objects. 

Thank you.

I believe that the graphics memory manager currently has a limit on any individual allocation being less than (4GB - 64KB), regardless of whether it's coming from system memory or video memory.

Try using multiple heaps and mapping them into a reserved resource to get something larger than 4GB.

I tried searching "graphics memory manager" and couldn't find any listed limits. 

On this page, I found the "Max Primitive Count" (The simplest primitive is a collection of points in a 3D coordinate system). So that limitation might be connected to buffers/resources?
https://msdn.microsoft.com/en-us/library/windows/desktop/ff476876(v=vs.85).aspx

Thanks for the tip.

Hello Hodgman, 

When checking D3D12_FEATURE_DATA_GPU_VIRTUAL_ADDRESS_SUPPORT

 MaxGPUVirtualAddressBitsPerResource = 40
 MaxGPUVirtualAddressBitsPerProcess = 40

I'm attempting to allocate about 5-12GB so 40 bits would be enough for that. 

------------

I will probably use a multiple heap or related method as a workaround later. But still interested if there is a way to allocate >4 GB.

Vinterberg, eventually it would matter but I don't think it would for this specific error from CreateCommittedResource. 
It gives an error when allocating a size greater than 2^32, so I have been testing with just a little over that value. Which is still several GB less than the current GPU card I am using. Also, I am watching my GPU with nvidia-smi so I can see live memory usage. 

The video memory manager I mentioned lives in DxgMms1.sys or DxgMms2.sys. It's responsible for allocating and managing memory, yes.

I doubt that the 4GB limit is well-documented anywhere, considering that up until recently it wasn't a limitation that anybody could really run into.