Location of buffer pools and compatibility of exit routines
IMS High Performance Unload always allocates buffer pools above the 16-MB line.
In DBT 2.2 HSSR, buffer pools are allocated above the 16-MB line only for VSAM data sets. In DBT 2.3 HSSR buffer pools are allocated above the 16-MB line for OSAM data sets also only when DFSMS 1.1 or later is used.
Because of these differences, you might need to link-edit your FABHURG1 exit routine or FABHFSU exit routine with the 31-bit addressing mode. For details, see the following topics: