Compaction
15. Backup compactions. Time Machine may compact its files on the backup volume, which should recover free space and provide sufficient for it to continue to make backups. T2M2 will detect this, and in the following two entries tells you how many times it has started these compactions, and how many have completed:
started 1 compactions to recover free space,
completed 1 compactions,
If no compaction is started or completed, no mention is made of compactions in the output.
Compaction tends to be triggered when free disk space on the backup volume is becoming low. Check the figures given for free space, and consider deleting old backups or backing up to a larger volume.
➜ Backups cancelled and errors
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