On Tue, Aug 31 2021, Taylor Blau wrote: > This pair of patches fixes a race where the .idx is moved into place > before the .rev file, allowing the pack to be in a state where it > appears a .rev file wasn't generated. > > This can cause Git to inadvertently take the slow "generate the > reverse index on-the-fly", which does not impact correctness, but is > unnecessarily slow when compared to reading the .rev file. > > The race is fixed by moving the .idx into place only after all other > pack-related files have already been written. The first patch fixes > the direct `pack-objects` case, and the second patch fixes `repack` > (which also renames pack files around). > > Thanks in advance for your review. > > Taylor Blau (2): > pack-write.c: rename `.idx` file into place last > builtin/repack.c: move `.idx` files into place last > > builtin/repack.c | 2 +- > pack-write.c | 12 ++++++------ > 2 files changed, 7 insertions(+), 7 deletions(-) I've reviewed this to the point of coming up with my own series on top of it, but it can be considered separately: https://lore.kernel.org/git/cover-0.3-00000000000-20210907T193600Z-avarab@xxxxxxxxx/ The only change (if any) would be to perhaps update the commit message(s) to note that the *.bitmap case is left, and that the promise of "closing the race" is still subject to the vagaries of our non-use of fsync() here, so pedantically speaking the race is still there. But even without those suggested changes: Reviewed-by: Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx>
