#VCP #Storage #Concept VAAI provides APIs which interact directly with the storage to offload certain tasks like copying,moving,zeroing etc. The tasks are handled by the storage and it's hardware, therefore it is usually faster than having the ESXi host executing those commands and results in a lower CPU utilization on the ESXi hosts. ## Offloading commands - Atomic Test & Sets(ATS) - performing metadata updates like locking overheads etc. - usually only heavily used when using thin disks & Snapshots - Extended Copy (full copy, copy offload, XCOPY) - copy operations for transferring data inside the same storage array. - can dramatically increase operations like Storage vMotion, cloning etc. - Block zeroing (Write Same) - for zeroing blocks like when creating eager-zeroed thick disks - or when writing to lazy-zeroed thick disks - Dead space reclamation (UNMAP) - conveys to storage which blocks are no longer in use - on thin provisioned on the array side this can allow storage array hardware to reuse no-longer needed blocks ## 🔗Resources