The IDMS CV startup can fail with error message DC390003 INSUFFICIENT REGION SIZE, STARTUP ABORTED and abend code U3994. Depending on what stage of the startup the error occurs, you may instead get error message DC390001 INSUFFICIENT REGION DETECTED AT STARTUP. This can happen after upgrading IDMS to a new release or after making SYSGEN changes.
The problem is caused by IDMS being unable to obtain enough storage. It is is most likely due to insufficient storage below the line but it could also be due to insufficient XA storage.
To resolve the problem check the following:
- The REGION parameter in the EXEC or JOB card may be too small, try increasing it.
- The FREESTG parameter in the PARM statement may be too high, try reducing it. When modifying the FREESTG parm, reduce it gradually until the CV comes up. Too small a value can cause problems with storage fragmentation later on.
- The storage pools or program pools in the SYSGEN may be too high, try reducing these in the SYSTEM statement.
- The XA storage pools may be too high in the SYSGEN, try reducing them.
- The CV may be picking up a mixture of CA IDMS modules from different releases, check the STEPLIB and LINKLIST datasets point to the correct release loadlib.
- Changes may have been made to the SYSGEN and not generated successfully, regenerate the system.