When you prune any of the repositories, still needs to download all existing snapshot files for all repositories (not the whole data, just the chunks which store each revision details – the meta chunks). The
/cache/chunks/ folder is used to store only these meta chunks that make up the snapshots.
If there are very many revisions or if some repositories contain large number of files, then the
/cache/chunks/ folder can grow to a surprisingly large size, reaching even more than 150GB.
This is recommended to run
prune from only a single repository, and use the
duplicacy prune -all -keep 0:365 -keep 30:70 -keep: 7:14 -keep 1:1 -threads 30