[PATCH 0/3] Simple reftable backend

This series comes from a conversation with Patrick Steinhardt at Gitlab, who have an interest in a more scalable ref storage system.

I unfortunately don't have business reasons to spend much time on this project anymore, and the original, sweeping migration has too many open questions.

I thought of an alternate approach, and I wanted to show it as input to discussions at the contributor summit.

I think the first part ("refs: push lock management into packed backend") is a good improvement overall, and could be landed separately without much tweaking.

The second part ("refs: alternate reftable ref backend implementation") is something open for discussion: the alternative "packed storage" is based on reftable, but it could conceivably be a different type of database/file format too. I think it's attractive to use reftable here, because over time more data (symrefs, reflog) could be moved into reftable.

Han-Wen Nienhuys (3):
  refs: push lock management into packed backend
  refs: move is_packed_transaction_needed out of packed-backend.c
  refs: alternate reftable ref backend implementation

 Makefile                        |    1 +
 config.mak.uname                |    2 +-
 contrib/workdir/git-new-workdir |    2 +-
 refs.c                          |    8 +
 refs/debug.c                    |   15 +
 refs/files-backend.c            |  182 +++-
 refs/packed-backend.c           |  150 +--
 refs/packed-backend.h           |   19 -
 refs/refs-internal.h            |    6 +
 refs/reftable-backend.c         | 1745 +++++++++++++++++++++++++++++++
 refs/reftable-backend.h         |    8 +
 11 files changed, 1941 insertions(+), 197 deletions(-)
 create mode 100644 refs/reftable-backend.c
 create mode 100644 refs/reftable-backend.h

base-commit: bda494f4043963b9ec9a1ecd4b19b7d1cd9a0518
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-1574%2Fhanwen%2Fsimple-reftable-backend-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-1574/hanwen/simple-reftable-backend-v1
Pull-Request: https://github.com/git/git/pull/1574