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| author | Eric Wong <e@80x24.org> | 2021-07-07 23:10:15 (GMT) |
|---|---|---|
| committer | Junio C Hamano <gitster@pobox.com> | 2021-07-08 00:21:12 (GMT) |
| commit | cf2dc1c238c6fd5f93c315a3045ccf95459701cd (patch) | |
| tree | bd576b3137f6943082e9b49f1eb1cc6c86e321f5 /object-store.h | |
| parent | 670b81a890388c60b7032a4f5b879f2ece8c4558 (diff) | |
| download | git-cf2dc1c238c6fd5f93c315a3045ccf95459701cd.zip git-cf2dc1c238c6fd5f93c315a3045ccf95459701cd.tar.gz git-cf2dc1c238c6fd5f93c315a3045ccf95459701cd.tar.bz2 | |
speed up alt_odb_usable() with many alternates
With many alternates, the duplicate check in alt_odb_usable()
wastes many cycles doing repeated fspathcmp() on every existing
alternate. Use a khash to speed up lookups by odb->path.
Since the kh_put_* API uses the supplied key without
duplicating it, we also take advantage of it to replace both
xstrdup() and strbuf_release() in link_alt_odb_entry() with
strbuf_detach() to avoid the allocation and copy.
In a test repository with 50K alternates and each of those 50K
alternates having one alternate each (for a total of 100K total
alternates); this speeds up lookup of a non-existent blob from
over 16 minutes to roughly 2.7 seconds on my busy workstation.
Note: all underlying git object directories were small and
unpacked with only loose objects and no packs. Having to load
packs increases times significantly.
Signed-off-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'object-store.h')
| -rw-r--r-- | object-store.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/object-store.h b/object-store.h index ec32c23..6077065 100644 --- a/object-store.h +++ b/object-store.h @@ -7,6 +7,8 @@ #include "oid-array.h" #include "strbuf.h" #include "thread-utils.h" +#include "khash.h" +#include "dir.h" struct object_directory { struct object_directory *next; @@ -30,6 +32,9 @@ struct object_directory { char *path; }; +KHASH_INIT(odb_path_map, const char * /* key: odb_path */, + struct object_directory *, 1, fspathhash, fspatheq); + void prepare_alt_odb(struct repository *r); char *compute_alternate_path(const char *path, struct strbuf *err); typedef int alt_odb_fn(struct object_directory *, void *); @@ -116,6 +121,8 @@ struct raw_object_store { */ struct object_directory *odb; struct object_directory **odb_tail; + kh_odb_path_map_t *odb_by_path; + int loaded_alternates; /* |