Release Notes

Optimize an SC Series array for an Oracle data warehouse
19 Optimizing Dell EMC SC Series Storage for Oracle OLAP Processing | 2009-M-BP-O
Volume space allocation statistics
3.4.5 Thin provisioning compared to preallocating storage
By default, all SC Series volumes are thin provisioned (the SC Series array allocates pages to the volume as
data is written to it). Alternatively, the whole volume can be preallocated at the time of creation. However,
regardless of the actual space consumption, the full volume size is reserved as used and cannot be
reassigned to other volumes.
Note: In most use cases, Dell EMC recommends thin provisioning volumes because it allows the array to
adapt to the actual space consumption.
Administrators can override this behavior on a per-volume basis. To allow preallocation of volume space, in
DSM, edit the SC Series settings, and under Preferences, check Allow Preallocate Storage Selection.
When creating a volume, a server must be selected before the Preallocate Storage option becomes
available.
Note: The preallocation operation is irreversible. To release the space, create a new thin provisioned volume,
migrate the data over, and delete the previously prellocated volume.
To realize the benefit of these thin-provisioned volumes, avoid preallocating storage on Oracle data files.
When creating the tablespaces and data files on these ASM disk groups, administrators can set an initial size
of each data file and specify the autoextend clause to include an autoextend size on each data file. This
allows SC Series array to allocate storage for the initial data file size. When the data files are full, additional
space will be allocated by the amount of autoextend size.