Darius,
Thanks for this detailed response. I did not realize that passing video card, USB (besides the fact it's broken in ESXi 5.1), and other PCI devices was "experimental" so to speak. So, thank you for this clarification.
You mentioned that the "intended use of PCI Passthrough is for users with high-performance storage or network controllers to connect those controllers directly to the VM which needs it at peak performance". This is of great interest to me. If so, does ESXi itself have drivers to support Thunderbolt so that a Thunderbolt storage device could be used as an external datastore?
If ESXi itself has no support for Thunderbolt-based datastores, can you comment on whether the Thunderbolt port pass-through has been tested and is something you would consider "supported" so that an OS X VM could use a Thunderbolt storage device as its DAS?
If the answer is yes to either (or both) of the above questions, do you know if the Drobo's Thunderbolt storage devices (Drobo 5D or Drobo Mini) would work in either of these two scenarios?
Finally, I came across a strange error message in my OS X VM running under ESXi 5 when using the ls -lcommand on the /Volumes directory of the OS X VM:
ls: VMware Shared Folders: Input/output error
total 8
lrwxr-xr-x 1 root admin 1 Feb 8 13:02 Macintosh HD -> /
drwxrwxr-x 9 root wheel 374 Feb 8 10:08 Recovery HD
I tried to google this error, and the only thing I can find is a reference to VMware Fusion and a bug in VMware Utilities. I actually installed VMware Utilities from the vSphere's Client into this OS X VM. So, it appears this actually could be the same issue, but my question is about the message itself. There's no concept of "Shared Folders" in ESXi because there's no host OS, correct? So, why is this error even displayed? Is this an example of VMware Utilities for OS X being ported from Fusion to ESXi?
Thanks!