eGPU support through Virtualisation with VMware Fusion 12 vs Boot Camp  

@eightarmedpet, VMWare released a Tech Preview back in March with better eGPU support. I haven't gotten around to it but there's settings for GPU in Preferences > Display.

With VMWare Fusion 12 including eGPU compatibility, I was wondering what the pro's and con's might be versus Bootcamp for gaming on Windows? Are there any scenarios where Fusion may be preferred?

I would imagine that Fusion could allow an up-to-date Windows 10, but I'm not sure what the resources cost would be of a virtual machine. I've personally never used this kind of software. Thanks.

@viciousmoth, If your Mac supports Boot Camp then it's a better option for gaming performance.

This is very similar to what parallels provides, and their latest update does improve directx 11 performance:

https://www.3dmark.com/fs/23293784  with Parallels 16

vs

https://www.3dmark.com/fs/22892121  with Parallels 15

vs

https://www.3dmark.com/fs/23222991  in Boot Camp 

all with i9 16 inch macbook pro + Radeon VII

Edit: Updated links, probably not showing up because I had Systeminfo turned off (I've had issues with it causing BSOD's).  I uploaded screenshots in case the links aren't viable.

These Mac virtualization solutions do not use native Windows AMD driver to control a GPU directly. They translate between their virtual GPU (shown as unknown in your screenshot) and your GPU so it's not as good as what you can do in Linux. Not sure if virtualization in Linux can take over a GPU connected via Thunderbolt - it might have to take over the entire Thunderbolt bus if that's possible?

Trying to replace bootcamp with a virtualized solution is futile as long as there is no PCI/GPU passthrough on macOS.

So I am really confused about this 🤷‍♂️

vt-d, which is _required_ for thunderbolt to even work at all, is absolutely supported by Mac OS X, and has been for some time.  Since 10.8, I believe?

So why do none of these virtualization solutions like VMWare Fusion or Parallels take advantage of it to allow for PCIe / thunderbolt passthrough to VMs?

Posted by: @nick_kay

So I am really confused about this 🤷‍♂️

vt-d, which is _required_ for thunderbolt to even work at all, is absolutely supported by Mac OS X, and has been for some time.  Since 10.8, I believe?

So why do none of these virtualization solutions like VMWare Fusion or Parallels take advantage of it to allow for PCIe / thunderbolt passthrough to VMs?

 

 

Just because vt-d is enabled in the UEFI and the OS uses it for DMA protection doesn't mean that the driver model for the OS supports handing off devices to virtualization programs.  I am pretty sure this is the functionality missing, and given Apple's recent initiatives to further lock 3rd party drivers out of the kernel I wouldn't expect this to change anytime soon.  (Not to mention that adding this feature when it probably won't be useable on Apple Silicon macs is probably a low low priority right now).

@nick_kay

I'm not certain about this, but I think both VMWare and Parallels build on the hypervisor framework built into macOS. I don't think this framework supports PCIe passthrough and that's why no software based on it does either. So it would be up to apple to add the functionality.

PCIe passthrough of an egpu seems like a really good way to drive yourself mad though, since most thunderbolt controllers are connected to the pch it would be hard to isolate just the thunderbolt connection or egpu to passthrough. I tried doing this on a linux host and it was bad enough, I'm not sure the tools to even unbind the egpu's pcie addresses from the host exist as a user in macOS.