undef/git-commit-vandalism
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

fsck: avoid reading every object twice

Browse Source 
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>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Nguyễn Thái Ngọc Duy 2011-11-07 09:59:25 +07:00 committed by Junio C Hamano
parent 473935188c
commit c9486eb04d
3 changed files with 39 additions and 21 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

42
builtin/fsck.c
View File

@ -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;

13
pack-check.c
View File

@ -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;
@ -120,6 +121,12 @@ static int verify_packfile(struct packed_git *p,
else if (check_sha1_signature(entries[i].sha1, data, size, typename(type)))
err = error("packed %s from %s is corrupt",
sha1_to_hex(entries[i].sha1), p->pack_name);
else if (fn) {
int eaten = 0;
fn(entries[i].sha1, type, size, data, &eaten);
if (eaten)
data = NULL;
}
free(data);
}
free(entries);
@ -150,7 +157,7 @@ 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;
@ -159,7 +166,7 @@ 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;

5
pack.h
View File

@ -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 *);