Yeah, that's a weird one. I wonder whether the partial clone filter
setting should also imply a config shutting off diffstats?
 - Emily

On Thu, Sep 22, 2022 at 7:24 AM Derrick Stolee [off-list ref] wrote:

On 9/21/2022 7:36 PM, Elijah Newren wrote:

quoted

On Wed, Sep 21, 2022 at 8:22 AM ZheNing Hu [off-list ref] wrote:

quoted

Here, we do have an object download, which occurred after the merge
completed, so there must be something happening after the merge which
needs the extra blob; if we keep reading...

quoted

 project1/file1 | 10 ++++++++++
 1 file changed, 10 insertions(+)

Ah, the 'helpful' diffstat.  It downloads blobs from a promisor remote
just so we can see what has changed, including in the area of the
project we don't care about.

(This is yet another reason it'd be nice to have a --restrict mode for
grep/diff/log/etc. for sparse-checkout uses, and an ability to make it
the default in some repo, so you could get just the diffstat within
the region of the project that you care about.  We're discussing such
an idea, but it isn't implemented yet.)

quoted

warning: This repository uses promisor remotes. Some objects may not be loaded.
blob_count1=11
blob_count2=11
blob_count3=12

The result shows that blob count doesn't change in git fetch, but in git merge.

If you add --no-stat to your merge command (or set merge.stat to
false), the extra blob will not be downloaded.

This is an interesting find! I wonder how many people are hitting this
in the wild. Perhaps merge.stat should be added to the optional, but
recommended config options in scalar.c.

Thanks,
-Stolee