`$GIT_DIR/refs` directory hierarchy.
A recommended practice to deal with a repository with too many
-refs is to pack its refs with `--all --prune` once, and
-occasionally run `git pack-refs --prune`. Tags are by
+refs is to pack its refs with `--all` once, and
+occasionally run `git pack-refs`. Tags are by
definition stationary and are not expected to change. Branch
heads will be packed with the initial `pack-refs --all`, but
only the currently active branch heads will become unpacked,