We have a 9 TB RDM.
Only 3.13 TB of that is being used.
VMware Guest is Windows 2012 R2.
The "volume" in the OS is a single 9 TB volume.
So, when we convert the RDM to VMDK (either live via Storage vMotion, or we can do cold migrate/convert as well):
The KB indicates that the contents of the RDM are copied to a new underlying VMDK (on the destination).
What's not clear is:
a) Assuming we leave everything as-is, does this make one large 9 TB VMDK?
b) If so, what type? Thick? Thin? Guessing Thick?
c) Anyway to "shrink" the actual VMDK to say, 3.5 TB during the conversion/migrate process?
Unfortunately the data set is millions upon millions of 1-2kb files, so an OS file copy will take weeks.
I briefly wondered about using some sort of partition software to shrink the partition/volume (although Windows can do this natively AFAIK) to say, 3.5 TB, but that doesn't change the RDM size.