diff options
author | Eric Wong <e@80x24.org> | 2021-07-08 02:10:17 +0300 |
---|---|---|
committer | Junio C Hamano <gitster@pobox.com> | 2021-07-08 07:27:58 +0300 |
commit | 33f379eee63a0529f85079857598ac6325d3aec5 (patch) | |
tree | 010f6c4d388fbdeabfc5ba2e29cb9c7996004bab | |
parent | 407532f82d3fdfd18d4ec276ddeb359e7c724aa6 (diff) |
make object_directory.loose_objects_subdir_seen a bitmap
There's no point in using 8 bits per-directory when 1 bit
will do. This saves us 224 bytes per object directory, which
ends up being 22MB when dealing with 100K alternates.
Signed-off-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
-rw-r--r-- | object-file.c | 11 | ||||
-rw-r--r-- | object-store.h | 2 |
2 files changed, 9 insertions, 4 deletions
diff --git a/object-file.c b/object-file.c index 2dd70ddf3a..91ded8c22a 100644 --- a/object-file.c +++ b/object-file.c @@ -2461,12 +2461,17 @@ struct oid_array *odb_loose_cache(struct object_directory *odb, { int subdir_nr = oid->hash[0]; struct strbuf buf = STRBUF_INIT; + size_t word_bits = bitsizeof(odb->loose_objects_subdir_seen[0]); + size_t word_index = subdir_nr / word_bits; + size_t mask = 1 << (subdir_nr % word_bits); + uint32_t *bitmap; if (subdir_nr < 0 || - subdir_nr >= ARRAY_SIZE(odb->loose_objects_subdir_seen)) + subdir_nr >= bitsizeof(odb->loose_objects_subdir_seen)) BUG("subdir_nr out of range"); - if (odb->loose_objects_subdir_seen[subdir_nr]) + bitmap = &odb->loose_objects_subdir_seen[word_index]; + if (*bitmap & mask) return &odb->loose_objects_cache[subdir_nr]; strbuf_addstr(&buf, odb->path); @@ -2474,7 +2479,7 @@ struct oid_array *odb_loose_cache(struct object_directory *odb, append_loose_object, NULL, NULL, &odb->loose_objects_cache[subdir_nr]); - odb->loose_objects_subdir_seen[subdir_nr] = 1; + *bitmap |= mask; strbuf_release(&buf); return &odb->loose_objects_cache[subdir_nr]; } diff --git a/object-store.h b/object-store.h index 6077065d90..ab6d469970 100644 --- a/object-store.h +++ b/object-store.h @@ -22,7 +22,7 @@ struct object_directory { * * Be sure to call odb_load_loose_cache() before using. */ - char loose_objects_subdir_seen[256]; + uint32_t loose_objects_subdir_seen[8]; /* 256 bits */ struct oid_array loose_objects_cache[256]; /* |