In repository having large number of refs, lstat for non-existing loose
objects makes `git fetch` slow.
This patch stores existing loose objects in hashmap beforehand and use
it to check existence instead of using lstat.
With this patch, the number of lstat calls in `git fetch` is reduced
from 411412 to 13794 for chromium repository.
I took time stat of `git fetch` disabling quickfetch for chromium
repository 3 time on linux with SSD.
* with this patch
8.105s
8.309s
7.640s
avg: 8.018s
* master
12.287s
11.175s
12.227s
avg: 11.896s
On my MacBook Air which has slower lstat.
* with this patch
14.501s
* master
1m16.027s
`git fetch` on slow disk will be improved largely.
Signed-off-by: Takuto Ikuta <tikuta@xxxxxxxxxxxx>
---
cache.h | 2 ++
fetch-pack.c | 22 +++++++++++++++++++---
sha1_file.c | 3 +++
3 files changed, 24 insertions(+), 3 deletions(-)
diff --git a/cache.h b/cache.h
index d06932ed0..db38db40e 100644
--- a/cache.h
+++ b/cache.h
@@ -1773,6 +1773,8 @@ struct object_info {
#define OBJECT_INFO_SKIP_CACHED 4
/* Do not retry packed storage after checking packed and loose storage */
#define OBJECT_INFO_QUICK 8
+/* Do not check loose object */
+#define OBJECT_INFO_SKIP_LOOSE 16
extern int sha1_object_info_extended(const unsigned char *, struct object_info *, unsigned flags);
/*
diff --git a/fetch-pack.c b/fetch-pack.c
index d97461296..1658487f7 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -711,6 +711,15 @@ static void mark_alternate_complete(struct object *obj)
mark_complete(&obj->oid);
}
+static int add_loose_objects_to_set(const struct object_id *oid,
+ const char *path,
+ void *data)
+{
+ struct oidset* set = (struct oidset*)(data);
+ oidset_insert(set, oid);
+ return 0;
+}
+
static int everything_local(struct fetch_pack_args *args,
struct ref **refs,
struct ref **sought, int nr_sought)
@@ -719,16 +728,21 @@ static int everything_local(struct fetch_pack_args *args,
int retval;
int old_save_commit_buffer = save_commit_buffer;
timestamp_t cutoff = 0;
+ struct oidset loose_oid_set = OIDSET_INIT;
+
+ for_each_loose_object(add_loose_objects_to_set, &loose_oid_set, 0);
save_commit_buffer = 0;
for (ref = *refs; ref; ref = ref->next) {
struct object *o;
+ unsigned int flag = OBJECT_INFO_QUICK;
- if (!has_object_file_with_flags(&ref->old_oid,
- OBJECT_INFO_QUICK))
- continue;
+ if (!oidset_contains(&loose_oid_set, &ref->old_oid))
+ flag |= OBJECT_INFO_SKIP_LOOSE;
+ if (!has_object_file_with_flags(&ref->old_oid, flag))
+ continue;
o = parse_object(&ref->old_oid);
if (!o)
continue;
@@ -744,6 +758,8 @@ static int everything_local(struct fetch_pack_args *args,
}
}
+ oidset_clear(&loose_oid_set);
+
if (!args->no_dependents) {
if (!args->deepen) {
for_each_ref(mark_complete_oid, NULL);
diff --git a/sha1_file.c b/sha1_file.c
index 1b94f39c4..c903cbcec 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -1262,6 +1262,9 @@ int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi,
if (find_pack_entry(real, &e))
break;
+ if (flags & OBJECT_INFO_SKIP_LOOSE)
+ return -1;
+
/* Most likely it's a loose object. */
if (!sha1_loose_object_info(real, oi, flags))
return 0;
--
2.16.2
