veertu

Actually gpu virtualization works quite similar to cpu. You don't pass a cpu core exclusively to a VM rather the cpu itself maintains independent contexts: for the host and each VM. When a CPU runs a VM it just switches the context. So is the GPU. You don't need two GPUs to make it work.

I hope in the near future Apple will release an API for GPU virtualization. In fact Intel Iris Pro devices already support GVT-d. The problem is that Iris Pro is only used in the expensive Macbook models, the cheaper one come with regular Iris that don't have hardware support for it

Currently in testing, in a few weeks we're hoping to release it on the AppStore

There will be soon!