Now that `refs_for_each_fullref_in()` has the ability to avoid
enumerating references matching certain pattern(s), use that to avoid
visiting hidden refs when constructing the ref advertisement via
receive-pack.
Note that since this exclusion is best-effort, we still need
`show_ref_cb()` to check whether or not each reference is hidden or not
before including it in the advertisement.
As was the case when applying this same optimization to `upload-pack`,
`receive-pack`'s reference advertisement phase can proceed much quicker
by avoiding enumerating references that will not be part of the
advertisement.
(Below, we're still using linux.git with one hidden refs/pull/N ref per
commit):
$ hyperfine -L v ,.compile 'git{v} -c transfer.hideRefs=refs/pull receive-pack --advertise-refs .git'
Benchmark 1: git -c transfer.hideRefs=refs/pull receive-pack --advertise-refs .git
Time (mean ± σ): 89.1 ms ± 1.7 ms [User: 82.0 ms, System: 7.0 ms]
Range (min … max): 87.7 ms … 95.5 ms 31 runs
Benchmark 2: git.compile -c transfer.hideRefs=refs/pull receive-pack --advertise-refs .git
Time (mean ± σ): 4.5 ms ± 0.2 ms [User: 0.5 ms, System: 3.9 ms]
Range (min … max): 4.1 ms … 5.6 ms 508 runs
Summary
'git.compile -c transfer.hideRefs=refs/pull receive-pack --advertise-refs .git' ran
20.00 ± 1.05 times faster than 'git -c transfer.hideRefs=refs/pull receive-pack --advertise-refs .git'
Signed-off-by: Taylor Blau <me@xxxxxxxxxxxx>
---
builtin/receive-pack.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index 1a8472eddc..bd5bcc375f 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -337,7 +337,8 @@ static void write_head_info(void)
{
static struct oidset seen = OIDSET_INIT;
- for_each_ref(show_ref_cb, &seen);
+ refs_for_each_fullref_in(get_main_ref_store(the_repository), "",
+ hidden_refs.v, show_ref_cb, &seen);
for_each_alternate_ref(show_one_alternate_ref, &seen);
oidset_clear(&seen);
if (!sent_capabilities)
--
2.41.0.44.gf2359540d2
