Data capture suppression enhancement

In IMS 15, you can use the Data capture suppression enhancement to prevent the Data Capture exit routine from being called unnecessarily. This enhancement allows you to prevent the Data Capture exit routine from being called for updates from a CCTL or ODBM address space.

Previously, the Data Capture exit routine was always called for application program activity on an IMS database if the exit routine was specified in the database definition (DBD). The exit routine would be called regardless of which program specification block (PSB) was active. Therefore, Data Capture exit routines were global and might have had a performance impact across the entire database system.

With this enhancement, the SUPPDCAPNAME= parameter is introduced to the DFSDFxxx member of the IMS PROCLIB data set. If you specify the job name of a CCTL or ODBM address space on the SUPPDCAPNAME= parameter, database updates invoked by the job are not captured by the Data Capture exit routine, even if the exit routine is specified on the EXIT= parameter of the DBD. Database or database segment updates that are invoked by jobs other than the one that is specified on the SUPPDCAPNAME= parameter continue to be captured by the Data Capture exit routine.

By using this enhancement to suppress database or database segment updates when those updates are made from a CCTL or ODBM address space, you can reduce CPU usage and improve the efficiency with which data is processed in your IMS environment.

This enhancement is delivered with APAR PH00728 (PTFs UI59377 and UI59378).

Do not enable this support in a replication environment if the updates made by the replication are replicated, also known as cascaded, to another system.

Log records

No log record changes were made for this enhancement, and products that use X'99' log data do not need to change if this enhancement is enabled.

Changes to defining IMS

The SUPPDCAPNAME= parameter is introduced to the DATABASE section of the DFSDFxxx member of the IMS PROCLIB data set.

Changes to troubleshooting for IMS

For a list of the messages and codes that are new or changed for this enhancement, see the IMS messages and codes row in the table in Documentation changes.

For a complete list of all of the new, changed, and deleted messages, and abend codes in IMS 15, see Message and code changes in IMS 15.

Documentation changes

The following table lists the publications that contain new or changed topics for the Data capture suppression enhancement. Publications that are not impacted by this enhancement are not included in the table.

Table 1. Links to topics that have new or changed content for this enhancement
Publication	Links to topics
Release planning	General planning information for IMS 15 New messages and codes for IMS 15 IMS 15 enhancements IMS 15 Database Manager continuous delivery functions Data capture suppression enhancement (new) (this topic)
System definition	DATABASE section of the DFSDFxxx member
Database administration	Database types and functions > Optional database functions Data Capture exit routines DBD parameters for Data Capture exit routines Data passed to and captured by the Data Capture exit routine Data Capture call functions Suppressing a Data Capture exit routine (new)
IMS messages and codes	DFS messages DFS4725I (new)
Exit routines	Data Capture exit routine
System utilities	Generation utilities > Database Description (DBD) Generation utility > DBDGEN statements DBD statements SEGM statements