[PATCH 3/4] fsck: avoid reading every object twice
- From
Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
- Date
- Nov 4, 2011, 15:47 UTC
- Message-ID
- <1320421670-518-4-git-send-email-pclouds@gmail.com>
- In-Reply-To
- <1320421670-518-1-git-send-email-pclouds@gmail.com>
During verify_pack() all objects are read for SHA-1 check. Then fsck_sha1() is called on every object, which read the object again (fsck_sha1 -> parse_object -> read_sha1_file).
Avoid reading an object twice, do fsck_sha1 while we have an object uncompressed data in verify_pack.
On git.git, with this patch I got:
$ /usr/bin/time ./git fsck >/dev/null 98.97user 0.90system 1:40.01elapsed 99%CPU (0avgtext+0avgdata 616624maxresident)k 0inputs+0outputs (0major+194186minor)pagefaults 0swaps
Without it:
$ /usr/bin/time ./git fsck >/dev/null 231.23user 2.35system 3:53.82elapsed 99%CPU (0avgtext+0avgdata 636688maxresident)k 0inputs+0outputs (0major+461629minor)pagefaults 0swaps
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> --- builtin/fsck.c | 42 +++++++++++++++++++++++++----------------- pack-check.c | 13 ++++++++++--- pack.h | 5 ++++- 3 files changed, 39 insertions(+), 21 deletions(-)
diff --git a/builtin/fsck.c b/builtin/fsck.c index 4ead98d..0603f64 100644 --- a/builtin/fsck.c +++ b/builtin/fsck.c @@ -282,14 +282,8 @@ static void check_connectivity(void) } } -static int fsck_sha1(const unsigned char *sha1) +static int fsck_obj(struct object *obj) { - struct object *obj = parse_object(sha1); - if (!obj) { - errors_found |= ERROR_OBJECT; - return error("%s: object corrupt or missing", - sha1_to_hex(sha1)); - } if (obj->flags & SEEN) return 0; obj->flags |= SEEN; @@ -332,6 +326,29 @@ static int fsck_sha1(const unsigned char *sha1) return 0; } +static int fsck_sha1(const unsigned char *sha1) +{ + struct object *obj = parse_object(sha1); + if (!obj) { + errors_found |= ERROR_OBJECT; + return error("%s: object corrupt or missing", + sha1_to_hex(sha1)); + } + return fsck_obj(obj); +} + +static int fsck_obj_buffer(const unsigned char *sha1, enum object_type type, + unsigned long size, void *buffer, int *eaten) +{ + struct object *obj; + obj = parse_object_buffer(sha1, type, size, buffer, eaten); + if (!obj) { + errors_found |= ERROR_OBJECT; + return error("%s: object corrupt or missing", sha1_to_hex(sha1)); + } + return fsck_obj(obj); +} + /* * This is the sorting chunk size: make it reasonably * big so that we can sort well.. @@ -627,17 +644,8 @@ int cmd_fsck(int argc, const char **argv, const char *prefix) prepare_packed_git(); for (p = packed_git; p; p = p->next) /* verify gives error messages itself */ - if (verify_pack(p)) + if (verify_pack(p, fsck_obj_buffer)) errors_found |= ERROR_PACK; - - for (p = packed_git; p; p = p->next) { - uint32_t j, num; - if (open_pack_index(p)) - continue; - num = p->num_objects; - for (j = 0; j < num; j++) - fsck_sha1(nth_packed_object_sha1(p, j)); - } } heads = 0; diff --git a/pack-check.c b/pack-check.c index e33ea79..372d6b2 100644 --- a/pack-check.c +++ b/pack-check.c @@ -42,7 +42,8 @@ int check_pack_crc(struct packed_git *p, struct pack_window **w_curs, } static int verify_packfile(struct packed_git *p, - struct pack_window **w_curs) + struct pack_window **w_curs, + verify_fn fn) { off_t index_size = p->index_size; const unsigned char *index_base = p->index_data; @@ -129,6 +130,12 @@ static int verify_packfile(struct packed_git *p, free(data); break; } + if (fn) { + int eaten = 0; + fn(entries[i].sha1, type, size, data, &eaten); + if (eaten) + data = NULL; + } free(data); } free(entries); @@ -159,7 +166,7 @@ int verify_pack_index(struct packed_git *p) return err; } -int verify_pack(struct packed_git *p) +int verify_pack(struct packed_git *p, verify_fn fn) { int err = 0; struct pack_window *w_curs = NULL; @@ -168,7 +175,7 @@ int verify_pack(struct packed_git *p) if (!p->index_data) return -1; - err |= verify_packfile(p, &w_curs); + err |= verify_packfile(p, &w_curs, fn); unuse_pack(&w_curs); return err; diff --git a/pack.h b/pack.h index 722a54e..70f3c29 100644 --- a/pack.h +++ b/pack.h @@ -70,10 +70,13 @@ struct pack_idx_entry { off_t offset; }; + +typedef int (*verify_fn)(const unsigned char*, enum object_type, unsigned long, void*, int*); + extern const char *write_idx_file(const char *index_name, struct pack_idx_entry **objects, int nr_objects, const struct pack_idx_option *, unsigned char *sha1); extern int check_pack_crc(struct packed_git *p, struct pack_window **w_curs, off_t offset, off_t len, unsigned int nr); extern int verify_pack_index(struct packed_git *); -extern int verify_pack(struct packed_git *); +extern int verify_pack(struct packed_git *, verify_fn fn); extern void fixup_pack_header_footer(int, unsigned char *, const char *, uint32_t, unsigned char *, off_t); extern char *index_pack_lockfile(int fd); extern int encode_in_pack_object_header(enum object_type, uintmax_t, unsigned char *);
-- 1.7.4.74.g639db