From: Patrick Steinhardt Date: Tue, 21 Oct 2025 14:13:22 GMT Subject: [PATCH v2 0/9] builtin/maintenance: introduce "geometric" strategy Message-ID: <20251021-pks-maintenance-geometric-strategy-v2-0-f0d727832b80@pks.im> In-Reply-To: <20251016-pks-maintenance-geometric-strategy-v1-0-18943d474203@pks.im> Hi, by default, git-maintenance(1) uses git-gc(1) to perform repository housekeeping. This tool has a couple of shortcomings, most importantly that it regularly does all-into-one repacks. This doesn't really work all that well in the context of monorepos, where you really want to avoid repacking all objects regularly. An alternative maintenance strategy is the "incremental" strategy, but this strategy has two downsides: - Strategies in general only apply to scheduled maintenance. So if you run git-maintenance(1), you still end up with git-gc(1). - The strategy is designed to not ever delete any data, but a full replacment for git-gc(1) needs to also prune reflogs, rereree caches and vanished worktrees. This patch series aims to fix both of these issues. First, the series introduces a new "geometric" maintenance task, which makes use of geometric repacking as exposed by git-repack(1) in the general case. In the case where a geometric repack ends up merging all packfiles into one we instead do an all-into-one repack with cruft packs so that we can still phase out objects over time. Second, the series extends maintenance strategies to also cover normal maintenance. If the user has configured the "geometric" strategy, we'll thus use it for both manual and scheduled maintenance. For backwards compatibility, the "incremental" strategy is changed so that it uses git-gc(1) for manual maintenance and the other tasks for scheduled maintenance. The series is built on top of b660e2dcb9 (Sync with 'maint', 2025-10-14) with tb/incremental-midx-part-3.1 at c886af90f8 (SQUASH??? play well with other topics by preemptively including "repository.h", 2025-09-29) merged into it. Changes in v2: - Make the geometric factor configurable via "maintenance.geometric-repack.splitFactor". - Wrap some overly long lines in our tests. - Link to v1: https://lore.kernel.org/r/20251016-pks-maintenance-geometric-strategy-v1-0-18943d474203@pks.im Thanks! Patrick --- Patrick Steinhardt (9): builtin/gc: remove global `repack` variable builtin/gc: make `too_many_loose_objects()` reusable without GC config builtin/maintenance: introduce "geometric-repack" task builtin/maintenance: make the geometric factor configurable builtin/maintenance: don't silently ignore invalid strategy builtin/maintenance: run maintenance tasks depending on type builtin/maintenance: extend "maintenance.strategy" to manual maintenance builtin/maintenance: make "gc" strategy accessible builtin/maintenance: introduce "geometric" strategy Documentation/config/maintenance.adoc | 49 +++++- builtin/gc.c | 278 ++++++++++++++++++++++++++++------ t/t7900-maintenance.sh | 246 ++++++++++++++++++++++++++++++ 3 files changed, 515 insertions(+), 58 deletions(-) Range-diff versus v1: 1: d16d9ac4f01 = 1: f14cf90529d builtin/gc: remove global `repack` variable 2: 2beb7edfdc1 = 2: 64fde2d3fb0 builtin/gc: make `too_many_loose_objects()` reusable without GC config 3: e4bcc347e76 ! 3: 9ba24540238 builtin/maintenance: introduce "geometric-repack" task @@ t/t7900-maintenance.sh: test_expect_success 'maintenance.incremental-repack.auto + rm -f "trace2.txt" && + GIT_TRACE2_EVENT="$(pwd)/trace2.txt" \ + git maintenance run --task=geometric-repack 2>/dev/null && -+ test_subcommand git repack -d -l --geometric=2 --quiet --write-midx packfiles && @@ t/t7900-maintenance.sh: test_expect_success 'maintenance.incremental-repack.auto + run_and_verify_geometric_pack 2 && + + # Both packfiles have 3 objects, so the next run would cause us -+ # to merge both packfiles together. This should be turned into ++ # to merge all packfiles together. This should be turned into + # an all-into-one-repack. + GIT_TRACE2_EVENT="$(pwd)/all-into-one-repack.txt" \ + git maintenance run --task=geometric-repack 2>/dev/null && @@ t/t7900-maintenance.sh: test_expect_success 'maintenance.incremental-repack.auto + +test_geometric_repack_needed () { + NEEDED="$1" -+ AUTO_LIMIT="$2" && ++ GEOMETRIC_CONFIG="$2" && + rm -f trace2.txt && + GIT_TRACE2_EVENT="$(pwd)/trace2.txt" \ -+ git ${AUTO_LIMIT:+-c maintenance.geometric-repack.auto=$AUTO_LIMIT} maintenance run --auto --task=geometric-repack && ++ git ${GEOMETRIC_CONFIG:+-c maintenance.geometric-repack.$GEOMETRIC_CONFIG} \ ++ maintenance run --auto --task=geometric-repack 2>/dev/null && + case "$NEEDED" in + true) + test_grep "\[\"git\",\"repack\"," trace2.txt;; @@ t/t7900-maintenance.sh: test_expect_success 'maintenance.incremental-repack.auto + # An empty repository does not need repacking, except when + # explicitly told to do it. + test_geometric_repack_needed false && -+ test_geometric_repack_needed false 0 && -+ test_geometric_repack_needed false 1 && -+ test_geometric_repack_needed true -1 && ++ test_geometric_repack_needed false auto=0 && ++ test_geometric_repack_needed false auto=1 && ++ test_geometric_repack_needed true auto=-1 && + + test_oid_init && + @@ t/t7900-maintenance.sh: test_expect_success 'maintenance.incremental-repack.auto + test_commit "$(test_oid blob17_1)" && + test_geometric_repack_needed false && + test_commit "$(test_oid blob17_2)" && -+ test_geometric_repack_needed false 257 && -+ test_geometric_repack_needed true 256 && ++ test_geometric_repack_needed false auto=257 && ++ test_geometric_repack_needed true auto=256 && + + # Force another repack. + test_commit first && + test_commit second && -+ test_geometric_repack_needed true -1 && ++ test_geometric_repack_needed true auto=-1 && + + # We now have two packfiles that would be merged together. As + # such, the repack should always happen unless the user has + # disabled the auto task. -+ test_geometric_repack_needed false 0 && -+ test_geometric_repack_needed true 9000 ++ test_geometric_repack_needed false auto=0 && ++ test_geometric_repack_needed true auto=9000 + ) +' + -: ----------- > 4: d1b805004b9 builtin/maintenance: make the geometric factor configurable 4: c9a6e576299 = 5: d6fa70640c2 builtin/maintenance: don't silently ignore invalid strategy 5: 3c82a91f152 = 6: 37f7793dab9 builtin/maintenance: run maintenance tasks depending on type 6: 78502ad6868 = 7: 4b15eac845c builtin/maintenance: extend "maintenance.strategy" to manual maintenance 7: 59a5450c44f = 8: eb75881b6ae builtin/maintenance: make "gc" strategy accessible 8: 51065b109fa = 9: 5c011e7a7e2 builtin/maintenance: introduce "geometric" strategy --- base-commit: 0bb2c786c2349dd6700727153c13d81cbfb41710 change-id: 20251015-pks-maintenance-geometric-strategy-580c58581b01