How can I enable the Dynamic Extend feature for my Datacom areas?

Document ID : KB000045305
Last Modified Date : 14/02/2018
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Question: 

How can I enable the Dynamic Extend feature for my Datacom areas?

 

Answer: 

To enable dynamic extend for and area you need to 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_name(PROD) 
1000 ALTER 
1500 DYNAMIC-EXTEND,C 
1500 DYN-EXT-TRACKS,100 
 
To enable dynamic extend for the IXX you need to change the DYNAMIC-EXTEND and DYN-EXT-TRACKS attributes in the database entity.
 
-UPD DATABASE,database_name(PROD) 
1000 ALTER 
1500 DYNAMIC-EXTEND,C 
1500 DYN-EXT-TRACKS,100 
 
To specify tracks instead of cylinders change the DYNAMIC-EXTEND attribute to specify T instead of C: 
 
-UPD AREA,area_name(PROD) 
1000 ALTER 
1500 DYNAMIC-EXTEND,T 
1500 DYN-EXT-TRACKS,100 
 
You can't limit the number of extents but the operating system has a limit of 16 extents. 

To turn off dynamic extend,  set the DYNAMIC-EXTEND attribute to N.

-UPD AREA,area_name(PROD) 
1000 ALTER 
1500 DYNAMIC-EXTEND,N 
 
Note you can also use the DYNAMIC_EXTEND console command to run an on-demand Dynamic Extend. See TEC608187 for details.