cacheback-snapshot 0.0.1

File system snapshotting tool that prioritizes speed and reducing redundant storage.

File system snapshot tool that prioritizes snapshot speed and reducing redundant storage.

How it works

cacheback achieves its goals of quick snapshots and minimized snapshot storage size by using hardlink features of modern filesystems for files whose contents are unchanged between snapshots. This is similar to how git tracks objects in a repository by storing a file's data based on its content hash. To further improve speed, a cache of the previous snapshot scan is stored which stores each file's last modification timestamp and these timestamps are compared before computing the file content hash. If the timestamp is unchanged, it is assumed that the file has not changed since the previous snapshot and is linked to the existing content stored on disk.

Here is a diagram visualizing this concept of files within snapshots being pointers to stored data based on content hash:

If a file is unchanged between multiple snapshots, each file will point to the same hash-named object and therefore the literal file content is only stored on disk one time. If snapshots are deleted and a given hashed content is no longer pointed to by any files in any snapshots, then the --gargbage-collect flag will prompt cacheback to purge these unused hash-named files to recover storage space.

Install

pip install cacheback