On Thu, 28 Aug 2025 at 19:05, Junio C Hamano [off-list ref] wrote:

Daniele Sassoli [off-list ref] writes:

quoted

When reading the output `git count-objects -v` there is a `garbage` field. At
first I thought this would highlight objects that are considered "garbage", i.e.
could be garbage collected. However, I kept noticing that this wasn't the case,
despite my repository having plenty of dangling objects (that where removed once
I run `git gc --prune=now`), garbage kept being 0.

count-objects is about quick housekeeping stats and does not (and
should never) analyze reachability like fsck does, which is required
to tell which objects are dangling.

Totally agree with this.

quoted

I then turned to reading the docs, which state:
garbage: the number of files in the object database that are neither
valid loose objects nor valid packs

I don't think I've ever seen a definition of an invalid object?
I tried adding random chars to an object, effectively corrupting
the repository(which `git fsck` correctly picked up), but
count-objects kept returning 0 at the garbage field.

count-objects is about quick housekeeping stats and does not (and
should never) analyze object contents like fsck does, which is
required to tell which objects are corrupt.

quoted

The only way I've been able to get count-objects to report some garbage is by
creating files in the packs directory (or in any of the sub-directories of
`objects` folder) with random names, like "test", or sometimes I've seen it
report the existence of lock files or even preserved files.

So my question is, am I fundamentally misunderstanding what garbage means, are
the docs simply unclear or is the functionality not working as expected?

Thanks for taking the time to read this and respond.
Dani

You are fundamentally understanding correctly.  The command tells
you it found a garbage when you do this:

    $ mkdir -p .git/objects/00 && >.git/objects/00/tmp-garbage
    $ git count-objects -v
    warning: garbage found: .git/objects/00/tmp-garbage

Do you both agree that the term garbage is somewhat misleading? I've spoken
about this both on Discord[1] and in person at the recent Git Mini Summit, and
both times people expected to see garbage-collectable objects being reported by
this field (which, as Junio says, wouldn't be correct, but that's what people
think of).
Other users also seem to be confused by this as shown by [2].

At the very least, I believe the documentation could do with some clarification
and maybe we should even look at changing the wording of the field.
I wanted to triple check my understand was correct before submitting a patch.

Thanks for your feedback.

[1]https://discord.com/channels/1042895022950994071/1156706741875130499/1408738703156973640
[2]https://stackoverflow.com/questions/30999879/git-garbage-size-out-of-control-need-understanding