borg analyze

borg [common options] analyze [options]

Common options
Archive filters — Archive filters can be applied to repository targets.
	-a PATTERN, --match-archives PATTERN	only consider archives matching all patterns. see “borg help match-archives”.
	--sort-by KEYS	Comma-separated list of sorting keys; valid keys are: timestamp, archive, name, id, tags, host, user; default is: timestamp
	--first N	consider first N archives after other filters were applied
	--last N	consider last N archives after other filters were applied
	--oldest TIMESPAN	consider archives between the oldest archive’s timestamp and (oldest + TIMESPAN), e.g. 7d or 12m.
	--newest TIMESPAN	consider archives between the newest archive’s timestamp and (newest - TIMESPAN), e.g. 7d or 12m.
	--older TIMESPAN	consider archives older than (now - TIMESPAN), e.g. 7d or 12m.
	--newer TIMESPAN	consider archives newer than (now - TIMESPAN), e.g. 7d or 12m.

Description

Analyze archives to find “hot spots”.

Borg analyze relies on the usual archive matching options to select the archives that should be considered for analysis (e.g. -a series_name). Then it iterates over all matching archives, over all contained files and collects information about chunks stored in all directories it encountered.

It considers chunk IDs and their plaintext sizes (we don’t have the compressed size in the repository easily available) and adds up added/removed chunks’ sizes per direct parent directory and outputs a list of “directory: size”.

You can use that list to find directories with a lot of “activity” - maybe some of these are temporary or cache directories you did forget to exclude.

To not have these unwanted directories in your backups, you could carefully exclude these in borg create (for future backups) or use borg recreate to re-create existing archives without these.