1 04/07/86  dm_set_journal_stamps
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 3 Syntax as a command:  dm_set_journal_stamps
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 5 
 6 Function: sets the time stamp for all journals currently in use to the
 7 time at which the command is invoked.
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10 Access required: You need re access to dm_admin_gate_.
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12 
13 Notes: The effect of altering the time to the present subverts the
14 write_ahead_log (WAL) protocol, which guarantees that modified control
15 intervals of protected data management (DM) files are not written to
16 disk until their before images have been safely stored in a before
17 journal.
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19 Without the protection imposed by the time stamp, sync-held pages (as
20 modified control intervals are called when they are detained in main
21 memory) can be flushed to disk prior to their before images.  In the
22 event of a system crash without emergency shutdown (ESD), some before
23 images may not be available on rollback during recovery.
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26 It may be necessary you invoke this command if before journals become
27 damaged, preventing transactions from being committed, or if there is
28 an unusually large number of sync-held pages, stalling system
29 performance.  This command provides a means of keeping the system
30 running instead of shutting it down.  Use this request only as a last
31 resort.