Local Cache
In order to speed up certain operations, restic manages a local cache of data.
The location of the cache directory depends on the operating system and the
environment; see Caching.
Each repository has its own cache sub-directory, consisting of the repository ID
which is chosen at init. All cache directories for different repos are
independent of each other.
Snapshots, Data and Indexes
Snapshot, Data and Index files are cached in the sub-directories snapshots,
data and index, as read from the repository.
Expiry
Whenever a cache directory for a repo is used, that directory’s modification
timestamp is updated to the current time. By looking at the modification
timestamps of the repo cache directories it is easy to decide which directories
are old and haven’t been used in a long time. Those are probably stale and can
be removed.