Re: [PATCH v3 0/4] pack-objects: support bitmaps and delta-islands with `--path-walk`

[Junio C Hamano <gitster@pobox.com>]

Taylor Blau <me@ttaylorr.com> writes:

> Note to the maintainer:
>
>  * This series is still based on 'ds/path-walk-filters' with Patrick's
>    'ps/clang-w-glibc-2.43-and-_Generic' merged in.
>
> Here is another small reroll of my series to make `--path-walk` work
> with reachability bitmaps and delta-islands.
>
> This round addresses Stolee's request to demonstrate the repack-size
> side of the integration between `--path-walk` and bitmap writing, and
> fixes an errant "grep" in the test suite.
>
> Changes since v2 include:
>
>  * p5311 now forces a fresh repack with '-F' when building its bitmapped
>    test repository. This avoids reusing deltas from a non-'--path-walk'
>    pack when we are trying to measure a pack produced by `--path-walk`.
>
>  * p5311 now records the size of the bitmapped pack, both with and
>    without `--path-walk`, to show that writing bitmaps during a
>    `--path-walk` repack does not lose the pack-size improvement that
>    `--path-walk` provides in repositories where it helps.
>
>  * The second patch's commit message has updated p5311 numbers from a
>    recent fluentui clone, fixing the "pack sizes" typo and documenting
>    the new bitmapped-pack-size comparison.
>
>  * The t5310 grep assertion now uses `test_grep`, as suggested by Junio.
>
> Outside of the above, the series is functionally unchanged.
>
> Thanks in advance for another look.
>
> Taylor Blau (4):
>   t/perf: drop p5311's lookup-table permutation
>   pack-objects: support reachability bitmaps with `--path-walk`
>   pack-objects: extract `record_tree_depth()` helper
>   pack-objects: support `--delta-islands` with `--path-walk`

Very cleanly implemented.  I am not confident that I have followed
the detailed logic around delta islands in the last step but the
earlier three patches looked trivially good.

Thanks.  Will replace.