ac/bitmap-lookup-table, was Re: What's cooking in git.git (Aug 2022, #09; Fri, 26)
- From
Jeff King <peff@peff.net>
- Date
- Aug 28, 2022, 12:50 UTC
- Message-ID
- <YwtkqmPSEikWPLv5@coredump.intra.peff.net>
- In-Reply-To
- <xmqqbks6ya5d.fsf@gitster.g>
On Fri, Aug 26, 2022 at 02:20:30PM -0700, Junio C Hamano wrote:
Show 15 quoted lines
> * ac/bitmap-lookup-table (2022-08-26) 6 commits > (merged to 'next' on 2022-08-26 at 7914c141eb) > + bitmap-lookup-table: add performance tests for lookup table > + pack-bitmap: prepare to read lookup table extension > + pack-bitmap-write: learn pack.writeBitmapLookupTable and add tests > + pack-bitmap-write.c: write lookup table extension > + bitmap: move `get commit positions` code to `bitmap_writer_finish` > + Documentation/technical: describe bitmap lookup table extension > > The pack bitmap file gained a bitmap-lookup table to speed up > locating the necessary bitmap for a given commit. > > Will merge to 'next'? > cf. <Ywf01YqJKNsGfffx@nand.local> > source: <pull.1266.v6.git.1660496112.gitgitgadget@gmail.com>
We may want this on top:
-- >8 -- Subject: pack-bitmap-write: drop unused pack_idx_entry parameters
Our write_selected_commits_v1() function takes an array of pack_idx_entry structs. We used to need them for computing commit positions, but since aa30162559 (bitmap: move `get commit positions` code to `bitmap_writer_finish`, 2022-08-14), the caller passes in a separate array of positions for us. We can drop the unused array (and its matching length parameter).
Likewise, when we added write_lookup_table() in 93eb41e240 (pack-bitmap-write.c: write lookup table extension, 2022-08-14), it receives the same array of positions. So its "index" parameter was never used at all.
Signed-off-by: Jeff King <peff@peff.net> --- pack-bitmap-write.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)
diff --git a/pack-bitmap-write.c b/pack-bitmap-write.c index 2cfc92f287..a213f5eddc 100644 --- a/pack-bitmap-write.c +++ b/pack-bitmap-write.c @@ -649,8 +649,6 @@ static const struct object_id *oid_access(size_t pos, const void *table) } static void write_selected_commits_v1(struct hashfile *f, - struct pack_idx_entry **index, - uint32_t index_nr, uint32_t *commit_positions, off_t *offsets) { @@ -685,8 +683,6 @@ static int table_cmp(const void *_va, const void *_vb, void *_data) } static void write_lookup_table(struct hashfile *f, - struct pack_idx_entry **index, - uint32_t index_nr, uint32_t *commit_positions, off_t *offsets) { @@ -808,10 +804,10 @@ void bitmap_writer_finish(struct pack_idx_entry **index, commit_positions[i] = commit_pos; } - write_selected_commits_v1(f, index, index_nr, commit_positions, offsets); + write_selected_commits_v1(f, commit_positions, offsets); if (options & BITMAP_OPT_LOOKUP_TABLE) - write_lookup_table(f, index, index_nr, commit_positions, offsets); + write_lookup_table(f, commit_positions, offsets); if (options & BITMAP_OPT_HASH_CACHE) write_hash_cache(f, index, index_nr);
-- 2.37.2.1039.gebf11fa8a3