SANtricity 11.8 Solutions

A resource-provisioned volume is a thick volume in an SSD volume group or pool, where drive capacity is allocated (assigned to the volume) when the volume is created, but the drive blocks are deallocated (unmapped). By comparison, in a traditional thick volume, all drive blocks are mapped or allocated during a background volume initialization operation in order to initialize the Data Assurance protection information fields and to make data and RAID parity consistent in each RAID stripe. With a resource provisioned volume, there is no time-bound background initialization. Instead, each RAID stripe is initialized upon the first write to a volume block in the stripe.

Resource-provisioned volumes are supported only on SSD volume groups and pools, where all drives in the group or pool support the NVMe Deallocated or Unwritten Logical Block Error Enable (DULBE) error recovery capability. When a resource-provisioned volume is created, all drive blocks assigned to the volume are deallocated (unmapped). In addition, hosts can deallocate logical blocks in the volume using the NVMe Dataset Management command. Deallocating blocks can improve SSD wear life and increase maximum write performance. The improvement varies with each drive model and capacity.

Resource provisioning is enabled by default on systems where the drives support DULBE. You can disable that default setting from Pools & Volume Groups. Disabling resource provisioning is a permanent action for existing volumes and cannot be reversed (i.e., you cannot re-enable resource provisioning for these volume groups and pools).

However, if you want to re-enable resource provisioning again for any new volumes you create, you can do so from Settings > System. Be aware that when you re-enable resource provisioning, only newly created volume groups and pools are affected. Any existing volume groups and pools will remain unchanged. If desired, you can also disable resource provisioning again from Settings > System.