As follow up to the Exadata as Code post, today I’m going to focus on one of the latest features added to our automation: PDB Snapshot Cloning.
PDB snapshot cloning is one of the best development options to offers in a CI/CD project. In an Exadata environment there are special requirements to implement before start using this technology: Sparse Grid Disks and Sparse ASM Disk Group ( description and step-by-step example is available here).
On Exadata, the PDB Snapshot beneficial of all Smart features including offload capabilities, with in addition space- and time-efficient provisioning.
After this brief introduction let’s see how the PDB Snapshot Cloning has been implemented on our Exadata as Code automation.
Exadata Sparse Storage Automation
Select the Oracle Container Database (CDB) where the PDB Snapshot Cloning should be activated, and with One-clickprovisioning the Sparse Grid disks and Sparse ASM disk group are created.
After the initial provisioning, the automation starts monitoring the space usage, automatically resizing it (increasing/decreasing) when necessary.
PDB Snapshot Cloning Automation
Same principle applies to the different PDB actions: One-click Provisioning/Decommissioning of the PDB Test Master and PDB Snapshot.
Those features are exposed via UI or API to the application developers, making them autonomous on the management of such space efficient database environment.
ASM remains the preferred option to achieve the best I/O performance, while ACFS introduces interesting features like DB snapshot to quickly and space efficiently provision new databases.
The performance gap between the two solutions is not negligible as reported below by the AWR – TOP Timed Events sections of two PDBs, sharing the same infrastructure, executing the same workload but respectively using ASM and ACFS storage:
PDBASM: Pluggable Database stored on ASM Disk Group
PDBACFS:Pluggable Database stored on ACFS File System
PDBASM AWR – TOP Timed Events and Other Stats
PDBACFS AWR – TOP Timed Events and Other Stats
Due to the different characteristics and results when ASM or ACFS is in use, it is not possible to give a generic recommendation. But case by case the choise should be driven by business needs like maximum performance versus fast and efficient database clone.