On Tue, 2007-12-04 at 21:09, Christopher Ekberg wrote: > (Embedded Sequoia.) > > I have a periodic process that creates a backup, compares the number > of backups to a maximum, and deletes any more than the maximum. It > then tries to truncate the recovery log to the point of the oldest > backup we have. This way, I can always install a new server by > restoring the backup and I don't need to keep unneeded statements > around. > > To truncate the recovery log, I'm calling deleteLogUpToCheckpoint > (checkpointNameOfOldestBackup). That function calls > deleteLogEntriesBeforeCheckpoint, which figures out the log id > associated with the backup, and deletes statements and checkpoints > between -1 and that. The problem is, if no statements have come in > since my last backup, the checkpoints for my other dumps will get > deleted, since they'd have the same log id.
I have near-identical processing but I take care that there has been some inserts into the recovery log since by the last backup / log purge. If no statements have been logged there is little point in doing another backup. > Am I doing something wrong? Calling the wrong function? I don't see > another good alternative. If this is a sequoia bug, you might change > the behavior of deleteLogEntriesAndCheckpointBetween to not delete > checkpoints that are still referenced by the dump table. What you are probably seeing is that more checkpoints than you are expecting are disappearing when you truncate the log. This is because checkpoints that share the same log identifier are considered to be *aliases* and are all removed when one checkpoint is removed. For me, this is more of an application level problem. Don't delete checkpoints that are in use by a dump that you still need. It might be that the customer wants 'hourly backups' (or whatever period) of the virtual database, but this is more a case of convincing the customer that it's not always appropriate. > Thanks, > Chris Regards, Nick p.s. Have you had problems _______________________________________________ Sequoia mailing list [email protected] https://forge.continuent.org/mailman/listinfo/sequoia
