A program can use checkpoint/restart while it has one or more entries
for a data space on its access list (DU-AL or PASN-AL). If the program
has specified on the ALESERV macro that the system is to ignore entries
made to the access list for the data space for checkpoint/restart
processing (CHKPT=IGNORE), the CHKPT macro processes successfully.
A program that specifies CHKPT=IGNORE assumes full responsibility
for managing the data space storage. Managing the data space storage
includes the following:
- If any program depends on the contents of the data space and the
data cannot be recreated or obtained elsewhere, the responsible program
must save the contents of the data space prior to the checkpoint operation.
- Once the checkpoint operation has completed, the responsible program
must perform the following during restart processing to successfully
manage the data space storage.
- Ensure that the data space exists. The original data space might
or might not exist. If the original data space does not exist, the
responsible program must issue DSPSERV CREATE to recreate the data
space.
- Issue ALESERV ADD of the data space, original or recreated, to
the program's access list to obtain a new ALET.
- If, in addition to having a dependency on the data space, any
program also depends on the contents of the data space storage, the
responsible program must refresh the contents of the data space storage.
The program must use the new ALET to reference the data space.
- The responsible program must make the new ALET available to any
program that has a dependency on the data space. The STOKEN, changed
or unchanged, must be made available to any program that needs to
issue ALESERV ADD to access the data space.
See z/OS DFSMSdfp Checkpoint/Restart information
about the CHKPT macro.