github.com/mckael/restic@v0.8.3/doc/cache.rst (about) 1 Local Cache 2 =========== 3 4 In order to speed up certain operations, restic manages a local cache of data. 5 This document describes the data structures for the local cache with version 1. 6 7 Versions 8 -------- 9 10 The cache directory is selected according to the `XDG base dir specification 11 <http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html>`__. 12 Each repository has its own cache sub-directory, consting of the repository ID 13 which is chosen at ``init``. All cache directories for different repos are 14 independent of each other. 15 16 The cache dir for a repo contains a file named ``version``, which contains a 17 single ASCII integer line that stands for the current version of the cache. If 18 a lower version number is found the cache is recreated with the current 19 version. If a higher version number is found the cache is ignored and left as 20 is. 21 22 Snapshots, Data and Indexes 23 --------------------------- 24 25 Snapshot, Data and Index files are cached in the sub-directories ``snapshots``, 26 ``data`` and ``index``, as read from the repository. 27 28 Expiry 29 ------ 30 31 Whenever a cache directory for a repo is used, that directory's modification 32 timestamp is updated to the current time. By looking at the modification 33 timestamps of the repo cache directories it is easy to decide which directories 34 are old and haven't been used in a long time. Those are probably stale and can 35 be removed. 36