Enabling read/write access to your data

To enable SHRLEVEL CHANGE

1. Make sure that a currently supported version of SUF (also known as XBM) (as described inOperational-considerationsSystem-requirements) is installed and available to CHECK PLUS.
2. SUF (also known as XBM) require a started task.
3. Create and activate the SUF (also known as XBM) configuration that contains the appropriate cache attributes.
4. Create and activate the SUF (also known as XBM) configuration that contains the appropriate cache attributes.
   For proper CHECK PLUS performance, make sure that SUF (also known as XBM) contain sufficient cache for the number of concurrent snapshots and the level of Db2 update activity at your site. For specific cache configuration information, see the SNAPSHOT UPGRADE FEATURE for DB2 documentation.
5. Specify the SHRLEVEL CHANGE option on your CHECK command statement.
6.  Specify the appropriate SUF (also known as XBM) subsystem ID with either the XBMID installation option (see XBMID=) or the XBMID command option.

SUF (also known as XBM)

To enable read and write access to your data during check processing, CHECK PLUS uses the snapshot-processing features of SUF (also known as XBM) to make a consistent image of the data. CHECK PLUS checks this image while your data remains available.

SUF (also known as XBM) are licensed, installed, and maintained separately from CHECK PLUS. You can use either SUF (also known as XBM), depending on the license that you have obtained:

• A license for the full version of the SUF (also known as XBM) product authorizes you to use both the I/O caching and snapshot-processing features of SUF (also known as XBM).
• A license for SUF (also known as XBM) authorizes you to use only the snapshot-processing features of SUF (also known as XBM).

For detailed information about SUF (also known as XBM), see the SNAPSHOT UPGRADE FEATURE for DB2 documentation.