How can the Dynamic Extend feature be enabled for a Datacom area?
To turn on and enable dynamic extend for a Datacom area, run DDUPDATE and change the DYNAMIC-EXTEND and DYN-EXT-TRACKS attributes in the area. The 1000 ALTER and 1500 transactions can be used to change the attributes directly in the CXX without having to close the database.
For example, to enable dynamic extend for an area with 100 cylinders code the following:
-UPD AREA,area-occurrence-name (PROD)
To enable dynamic extend for the IXX change the DYNAMIC-EXTEND and DYN-EXT-TRACKS attributes in the database entity.
-UPD DATABASE,database-occurrence-name (PROD)
To specify tracks instead of cylinders change the DYNAMIC-EXTEND attribute to specify T instead of C:
To turn off dynamic extend, set the DYNAMIC-EXTEND attribute to N.
The number of extents is limited by the operating system; there is a limit of 16 extents for non-SMS datasets. SMS allows for more extents.
The DYNAMIC_EXTEND console command can be used to run an on-demand Dynamic Extend. Please refer to Knowledge Base article 9503, titled "How to extend a Datacom area while the database is open" for more details.