REORG to reduce segment size new DBD

Floramq · New User Joined: 18 May 2017 Posts: 4 Location: CAnada

Hi, does anyone know how to reduce the segment size using User exit in the REORG ?
both old and new DBD have the segment defined as Fixed length. I want to reduce from 472 to 120 bytes

First:I tried running just unload with old DBD and reload with new DBD, hoping IMS would just truncate the extra data. I kept getting S0C4 in HPSRIOIN offset 469E

Next:I tried to create a user exit in the UNLOAD where I would modify the segments to smaller length. This just seems to go into a loop, no error is returned.. Then I've read this is basically not allowed because it is defined as Fixed Length in DBD

Should the first idea work, but maybe some change in parameters needed ?
Thanks in advance !
Flora

PeterHolland · Posted: Thu Oct 15, 2020 4:04 pm

DBDGEN/ACBGEN????

Floramq · New User Joined: 18 May 2017 Posts: 4 Location: CAnada

Hi Peter, thanks for this.. I am an application programmer working with the IMS DBA and he took care of the DBDGEN/ACBGEN etc... what we determined (after contacting IBM) was that the High Performance Utilities did not work for this scenario..
When we use the vanilla IBM Unload/ Reload it works without any User Exit
The unload wrote out the segments at the longer length (using OLD DBD) and the RELOAD read them in , truncated and created the IMS Segments with the correct length in the new DBD. (the last part is exactly what the manual says it should do, but it doesn't wok in HPUNLOAD utility version, gets S0C4. )
Thanks very much for answering.
Flora