The save-active-time for an object can be useful when you determine which recovery procedures to use after you restore objects from the media. All of the changes made to the object before the save active timestamp will be present for the object on the save-while-active media. The changes made to the object after the save active timestamp will not be present for the object on the save-while-active media.
If you specify UPDHST(*YES) on the save command, the server records the date and time that it performs a save operation for an object. The server takes the timestamp early during the save preprocessing phase. The timestamp identifies when the save operation started for the object. This timestamp is the save-time for the object. Multiple objects that you save with one save request will have the same save time if they all reside in the same library. This timestamp displays in the save date/time field when you use the Display Object Description (DSPOBJD) command displays.
The save-while-active function introduces an additional timestamp that relates to save processing. This additional timestamp is the save-active-time for an object. The save-active-time identifies the time an object that you saved with the save-while-active function object reached the checkpoint. The save-active-time is the same for all of the objects that reach a checkpoint together.
When you use the Display Object Description (DSPOBJD) command, the save-active-time displays in the save active date/time field. The server only updates the save-active-time for an object if you specify UPDHST(*YES) on the save command when you request the save-while-active operation.
Some objects do not require special save-while-active checkpoint processing. Therefore the save-while-active timestamp is the same time that the object's description is saved. Examples of this are object types *JOBQ and *OUTQ that have only their descriptions saved, not their contents. This is also true for files that do not have any members.
For physical file members, the last save date/time information that the DSPFD command identifies is either the last save-time or the last save-active-time. The information that displays depends on which type of save operation you last performed for each of the members.
The recovery considerations do not apply if you are using the save-while-active function to reduce your save-outage time.
This consideration applies to journaled objects that are saved with the save-while-active function. The start of save journal entry in journal contains both the save-time and save-active-time. The object saved journal entry in the journal also contains both the save-time and save-active-time. Look for the journal entry that identifies when the journaled file member reached the checkpoint. All journal entries after this journal entry for a journaled object will not be reflected in the data that is saved during a save-while-active operation. This information may be useful when you determine what recovery procedures are necessary after restoring journaled objects from the save-while-active media.