git-prune-packed

git prune-packed [-n|--dry-run]

-n, --dry-run
    Do not actually prune, just show what would be pruned.
This is useful for previewing the effects of the command without making any changes to the repository.

git prune-packed is a low-level "plumbing" command in Git used for repository maintenance. Its primary function is to remove loose objects from the .git/objects directory that are already contained within one or more .pack files. When Git packs objects, the original loose objects become redundant. While git gc (garbage collection) usually handles this, sometimes loose objects might remain after a repack operation or if git gc is not thorough enough. This command helps to reclaim disk space by identifying and deleting these unnecessary loose objects, ensuring that only the most efficient representation (packed objects) of the data is kept when possible. It's often run implicitly by other Git commands or scripts rather than directly by end-users.

This is a plumbing command; it's generally not invoked directly by end-users. Higher-level commands like git gc typically handle this pruning implicitly as part of a larger cleanup process.
It only removes loose objects that are packed. It does not prune unreachable loose objects that are not packed (that's git prune).
Care should be taken when using this command directly, although the --dry-run option provides a safe way to preview changes.

While git gc is the primary command for repository maintenance, git prune-packed plays a specific role in ensuring that loose objects which have been successfully included in a pack file are removed. This prevents a repository from accumulating redundant loose objects, which could otherwise waste disk space.

As a "plumbing" command, git prune-packed is designed to be used by other Git commands or scripts rather than directly by an end-user. This makes it a building block for more complex Git operations and maintenance scripts. Users typically interact with git gc, which orchestrates various pruning and packing operations, often including git prune-packed internally.

The git-prune-packed command has been a part of Git since its early days, contributing to its robust object management system. It was designed to address the specific scenario of cleaning up loose objects that become redundant after they've been packed into a .pack file, ensuring efficient disk space usage and maintaining repository hygiene. Its plumbing nature reflects Git's modular design, where lower-level tasks are exposed for scripting and higher-level commands.

git gc(1), git prune(1), git repack(1), git count-objects(1)