Space reclamation on 3PAR Thin Volumes using the Oracle ASRU utility

[ToddPrice]

The HPE 3PAR Storage Array provides Automatic Data Reduction features like Thin Volumes, Compression and Deduplication. This quick blog post is to cover a utility that can be used for freeing data on Thin Volumes back to the 3PAR Storage Array. Oracle Automatic Storage Reclamation Utility is a free download from Oracle.

As tables and other objects are populated in an Oracle database with 3PAR Storage, the array dynamically allocates the space as needed. This allocation of space can happen through normal transactions or the migration of data to the Oracle 3PAR Volumes.  

When databases and database objects are removed from the Oracle installation there is old data stranded in the 3PAR Storage Array. When the HPE 3PAR detects blocks with a zero value through the ASIC, those blocks get returned to the free pool and are made available for use by other provisioned volumes on the array.  See the video below which will demonstrate a step by step approach how the Oracle ASRU utility works. Also see the links below to Oracle’s ASRU whitepaper for more details, the link to download the ASRU utility and documented bug scenarios by Oracle..

ASRU Demo Video

 ASRU Demo

ASRU Demo Video

Link for the Oracle ASRU whitepaper:  Oracle Automatic Storage Management and Thin Reclamation

Link to download utility:  ASRU for Oracle Database - Enterprise Edition - Version 11.2.0.2 and later   (requires Oracle MySupport Account login)

The tool is supported by Oracle. Be aware of the following bugs:  (requires Oracle MySupport Account login)

Bug 11904676 - ASRU RESIZE WAS NOT SUCCESSFUL WHEN ASM ALLOCATION UNIT SIZE IS 32MB

Bug 13871861 - ASRU operates on the incorrect disks after a DISKGROUP is cloned
Bug 11904746 - data corruption is observed after the ASRU operation

General discussion is ALWAYS welcome!

Best Regards

Todd – HPE Technical Marketing Engineering – Oracle Solutions