Sometimes servers retain client-related data in address spaces and dataspaces other than the client's, which means this data will not be in the dump. For this reason, server code can modify the contents of an SVC dump to provide additional problem determination data by creating a tailored SVC dump exit. This feature allows a requestor to specify a dump request without identifying related server address, dataspaces, and storage areas, which could be unknown and dynamic in nature.
The server code provider can create these SVC dump exits without modifying module IEAVTSXT. The CSVDYNEX macro identifies the exit load module and associates it with the IEASDUMP.SERVER resource. The exit is allowed to scan the current dump request and determines if data should be added to the dump. The data is added to the dump by identifying it in the appropriate SDMSE_OUTPUT area. For additional details, see IEASDUMP.SERVER Dynamic Exit Processing in z/OS MVS Programming: Authorized Assembler Services Guide.
The tailored SVC dump exits are not called in any particular order. To ensure that the current requests are presented to an exit, the dump request is updated between exit invocations. If an exit adds data to the dump, every exit is re-invoked until no additional changes are made. Because of the additional processing required, tailored SVC dump exits do not receive control by default for SDUMPX macro requests. To cause the exit processing to take place, you must specify SDATA=SERVERS in the SDUMPX macro.
SDATA=SERVERS is in force for all operator Dump and SLIP SVC dump requests.