Emulator

This option enables command submission on a different thread. This is not a conventional multi-threading in Vulkan, and I find the option to be confusing.
A conventional model is that there are multiple threads recording work in command buffers, but then it gets submitted at some point on a queue that is also responsible for other things. Vulkan driver is not expected to do heavy lifting at submission time - it merely passes down the command buffers to the HW scheduler, conceptually speaking.

See fore more details: https://developer.nvidia.com/sites/default/files/akamai/gameworks/blog/munich/mschott_vulkan_multi_threading.pdf