Preparing to use shared data tables support

To use SDT support, you must perform the following tasks. Some of them will already have been done for an installation that currently uses function shipping and/or data tables.

Load modules

Table 2 shows the load modules to be installed in your CICS system in order to use SDT.

Table 2. Load modules in SDT
Load module Load library How loaded Description
DFHDTINS SDFHLOAD CICS load above the 16MB line Initialization
DFHDTSVC SDFHLINK MVS LOAD above the 16MB line from link-list Performs all functions that need MVS authorization
DFHDTFOR SDFHAUTH MVS LOAD above the 16MB line Data table FOR module
DFHDTAM SDFHAUTH MVS LOAD into subpool 252 storage above the 16MB line Data table access manager. It includes code that is executed in cross-memory mode from an AOR
DFHDTAOR SDFHAUTH MVS LOAD above the 16MB line Data table AOR module
DFHDTCV SDFHLINK MVS LOAD into ECSA from link-list Connection validation (AOR)
DFHDTXS SDFHAUTH MVS LOAD into ECSA Connection security checking (FOR)
DFHMVRMS SDFHLINK MVS LOAD above the 16MB line from link-list Resource manager EOT/EOM interface code

Storage occupancy

The total size of the modules that occupy storage above the 16MB line is about 41KB. For modules that are in ECSA storage, about 1.5KB are required for each logged-on FOR, and about 0.5KB for each AOR.

The modules are all eligible for inclusion in the link pack area (LPA), but only DFHDTFOR, DFHDTAM, DFHDTAOR, and possibly DFHDTCV are used sufficiently frequently to be worth considering.

Related concepts
MVS JCL requirements when using shared data tablesPlanning to use data tables
Performance benefits of data tables
Selecting files for use as data tables
Security checking for data tables
Shared data tables support on different releases of CICS
[[ Contents Previous Page | Next Page Index ]]