Re: What's cooking in git.git (Nov 2023, #04; Thu, 9)

[Taylor Blau <me@ttaylorr.com>]

On Thu, Nov 09, 2023 at 02:40:28AM +0900, Junio C Hamano wrote:
> * tb/merge-tree-write-pack (2023-10-23) 5 commits
>  - builtin/merge-tree.c: implement support for `--write-pack`
>  - bulk-checkin: introduce `index_tree_bulk_checkin_incore()`
>  - bulk-checkin: introduce `index_blob_bulk_checkin_incore()`
>  - bulk-checkin: generify `stream_blob_to_pack()` for arbitrary types
>  - bulk-checkin: extract abstract `bulk_checkin_source`
>
>  "git merge-tree" learned "--write-pack" to record its result
>  without creating loose objects.
>
>  Comments?
>  source: <cover.1698101088.git.me@ttaylorr.com>

This series received a couple of LGTMs from you and Patrick:

  - https://lore.kernel.org/git/xmqqo7go7w63.fsf@gitster.g/#t
  - https://lore.kernel.org/git/ZTjKmcV5c_EFuoGo@tanuki/

Johannes had posted some comments[1] about instead using a temporary
object store where objects are written as loose that would extend to git
replay. Like Peff mentions[2] below in that thread, that approach would
still involve writing loose objects, and it is the goal of my series to
avoid doing so.

I demonstrated in a follow-up thread[3] that my approach of using the
bulk-checkin and tmp-objdir APIs does extend straightforwardly to 'git
replay'. This works by writing out one pack per replay step in a
temporary object directory, and then running 'git repack -adf' on that
temporary object directory before migrating a single pack containing all
new objects back into the main object store.

I am fairly confident that tb/merge-tree-write-pack is ready to go. I'll
spin off a separate thread based on that branch and cc/git-replay as a
non-RFC series that extends this approach to 'git replay', so we'll be
ready to go there once Christian's series progresses.

[1]: https://lore.kernel.org/git/0ac32374-7d52-8f0c-8583-110de678291e@gmx.de/
[2]: https://lore.kernel.org/git/20231107034224.GA874199@coredump.intra.peff.net/
[3]: https://lore.kernel.org/git/cover.1699381371.git.me@ttaylorr.com/

Thanks,
Taylor