[PATCH] fetch-pack: trace packfile URI downloads
- From
Ted Nyman <tnyman@openai.com>
- Date
- Jul 26, 2026, 08:33 UTC
- Message-ID
- <20260726083310.16180-2-tnyman@openai.com>
When a protocol v2 fetch includes packfile URIs, the client downloads each advertised pack in a separate http-fetch process. Existing Trace2 regions cover negotiation, but not the time spent downloading these packs or the number of advertised URIs.
Add a Trace2 region around the packfile URI download loop and record the number of URIs. This makes the cost of downloading external packs visible without emitting an event for each pack.
Extend the existing packfile URI test to verify the region and count.
Signed-off-by: Ted Nyman <tnyman@openai.com> --- fetch-pack.c | 12 ++++++++++++ t/t5702-protocol-v2.sh | 7 ++++++- 2 files changed, 18 insertions(+), 1 deletion(-)
diff --git a/fetch-pack.c b/fetch-pack.c index 29c41132ee..701a23f808 100644 --- a/fetch-pack.c +++ b/fetch-pack.c @@ -1886,6 +1886,13 @@ static struct ref *do_fetch_pack_v2(struct fetch_pack_args *args, } } + if (packfile_uris.nr) { + trace2_region_enter("fetch-pack", "packfile-uris", + the_repository); + trace2_data_intmax("fetch-pack", the_repository, + "packfile-uris/count", packfile_uris.nr); + } + for (i = 0; i < packfile_uris.nr; i++) { int j; struct child_process cmd = CHILD_PROCESS_INIT; @@ -1936,6 +1943,11 @@ static struct ref *do_fetch_pack_v2(struct fetch_pack_args *args, repo_get_object_directory(the_repository), packname)); } + + if (packfile_uris.nr) + trace2_region_leave("fetch-pack", "packfile-uris", + the_repository); + string_list_clear(&packfile_uris, 0); strvec_clear(&index_pack_args); diff --git a/t/t5702-protocol-v2.sh b/t/t5702-protocol-v2.sh index 74a2b7730b..537deff7b3 100755 --- a/t/t5702-protocol-v2.sh +++ b/t/t5702-protocol-v2.sh @@ -1223,7 +1223,7 @@ configure_exclusion () { test_expect_success 'part of packfile response provided as URI' ' P="$HTTPD_DOCUMENT_ROOT_PATH/http_parent" && - rm -rf "$P" http_child log && + rm -rf "$P" http_child log trace2 && git init "$P" && git -C "$P" config "uploadpack.allowsidebandall" "true" && @@ -1238,10 +1238,15 @@ test_expect_success 'part of packfile response provided as URI' ' configure_exclusion "$P" other-blob >h2 && GIT_TRACE=1 GIT_TRACE_PACKET="$(pwd)/log" GIT_TEST_SIDEBAND_ALL=1 \ + GIT_TRACE2_EVENT="$(pwd)/trace2" \ git -c protocol.version=2 \ -c fetch.uriprotocols=http,https \ clone "$HTTPD_URL/smart/http_parent" http_child && + test_grep \"event\":\"region_enter\".*\"label\":\"packfile-uris\" trace2 && + test_grep \"key\":\"packfile-uris/count\",\"value\":\"2\" trace2 && + test_grep \"event\":\"region_leave\".*\"label\":\"packfile-uris\" trace2 && + # Ensure that my-blob and other-blob are in separate packfiles. for idx in http_child/.git/objects/pack/*.idx do