In do_fetch_pack_v2(), the "sought" array is sorted by name, and it is
not subsequently reordered (within the function). Therefore,
receive_wanted_refs() can assume that "sought" is sorted, and can thus
use a binary search when storing wanted-refs retrieved from the server.
Replace the existing linear search with a binary search. This improves
performance significantly when mirror cloning a repository with more
than 1 million refs.
Signed-off-by: Jonathan Tan <jonathantanmy@xxxxxxxxxx>
---
fetch-pack.c | 19 ++++++++++---------
1 file changed, 10 insertions(+), 9 deletions(-)
diff --git a/fetch-pack.c b/fetch-pack.c
index e69993b2eb..e8266bd45a 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -1298,6 +1298,11 @@ static void receive_shallow_info(struct fetch_pack_args *args,
}
}
+static int cmp_name_ref(const void *name, const void *ref)
+{
+ return strcmp(name, (*(struct ref **)ref)->name);
+}
+
static void receive_wanted_refs(struct packet_reader *reader,
struct ref **sought, int nr_sought)
{
@@ -1305,20 +1310,16 @@ static void receive_wanted_refs(struct packet_reader *reader,
while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
struct object_id oid;
const char *end;
- int i;
+ struct ref **found;
if (parse_oid_hex(reader->line, &oid, &end) || *end++ != ' ')
die(_("expected wanted-ref, got '%s'"), reader->line);
- for (i = 0; i < nr_sought; i++) {
- if (!strcmp(end, sought[i]->name)) {
- oidcpy(&sought[i]->old_oid, &oid);
- break;
- }
- }
-
- if (i == nr_sought)
+ found = bsearch(end, sought, nr_sought, sizeof(*sought),
+ cmp_name_ref);
+ if (!found)
die(_("unexpected wanted-ref: '%s'"), reader->line);
+ oidcpy(&(*found)->old_oid, &oid);
}
if (reader->status != PACKET_READ_DELIM)
--
2.21.0.197.gd478713db0
