your end goal is to have a 10+2 configuration. that is where your column count requirement comes from.
New-VirtualDisk -StoragePoolFriendlyName MetroPlex -FriendlyName DualParity -ResiliencySettingName Parity -ProvisioningType Thin -PhysicalDiskRedundancy 2 -WriteCacheSize 100GB -Size 27TB -NumberOfColumns 12
Yup I've been running them with the /k and /x switches, and the equivalent for Optimize-Volume to no effect.run defrag /x (file consolidation) as well as defrag /k
defrag /k (slab consolidation) is not 100% effective.
this is also why I was recommending a temp 6 column migration vdisk. to free up more space from the 1st vdisk.
Chris
New-VirtualDisk -StoragePoolFriendlyName MetroPlex -FriendlyName DualParity -ResiliencySettingName Parity -ProvisioningType Thin -WriteCacheSize 100GB -Size 27.3TB -NumberOfColumns 12 -PhysicalDiskRedundancy 2