Long running transactions that do not commit their changes can fill the journals because the ARCHIVE JOURNAL utility is unable to remove the BFOR images for uncommitted transactions. The ARCHIVE JOURNAL utility generates a warning message when the journal file that is being archived remains nearly full after the process completes. The ARCHIVE_JOURNAL_WARNING_PERCENT SYSIDMS parameter dictates the threshold used to trigger the message. If this message appears, it indicates that the journal files are filling and corrective action may be needed.
When the journals are close to being full, the CA IDMS system halts database activity. To recover from this situation, the task that is filling the journals must be canceled.
To assist in this process, the following message is written for each task that is waiting to write to a full journal file:
DC205024 Journal Write waiting on full Journal
The message will be repeated every few seconds until tasks are no longer waiting on a full journal.
To recover from this situation, the task that is filling the journal files must be identified and aborted. To assist in this effort, CA IDMS will display message DC205030 showing details of the task causing the journal swap. This is most likely the task causing excessive journaling activity, although it may not be. To determine if this is the offending task, display detailed transaction information by issuing DCMT DISPLAY TRANSACTION commands or using the transaction detail function of the real time monitor within CA IDMS Performance Monitor.
Look for the transaction that has written the largest number of BFOR journal images. Cancel its associated task by issuing a DCMT VARY ACTIVE TASK command.
When the cancelled task has terminated, issue a DCMT VARY JOURNAL command to force the central version to swap to a new active journal file allowing the full file to be offloaded and condensed by ARCHIVE JOURNAL. It is likely that DCMT VARY JOURNAL will need to be issued more than once, since several journal files may have filled and require offloading.
Once the system swaps back to the first journal file on which tasks waited, processing should continue without the need for further intervention.
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