Re: [PATCH] pack-objects: trace pack bytes written

From: Friel <redacted>

We want to measure how compression settings affect push performance on
the client. Different settings can produce different-sized packs from
the same objects. Trace2 records the object count, but we also need the
pack size to compare those settings.

Add a write_pack_file/wrote_bytes Trace2 datum alongside
write_pack_file/wrote. Count packs written to stdout or disk, including
each pack's header and trailing checksum. When pack.packSizeLimit splits
the output, report the sum of the pack sizes.

Signed-off-by: Friel <redacted>
---
 builtin/pack-objects.c |  7 +++++++
 t/t5300-pack-object.sh | 24 ++++++++++++++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 1ec5b6f206..bbf1adb437 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c

@@ -1337,6 +1337,7 @@ static void write_pack_file(void)
 	uint32_t nr_remaining = nr_result;
 	time_t last_mtime = 0;
 	struct object_entry **write_order;
+	off_t bytes_written = 0;
 
 	if (progress > pack_to_stdout)
 		progress_state = start_progress(the_repository,

@@ -1347,6 +1348,7 @@ static void write_pack_file(void)
 	do {
 		unsigned char hash[GIT_MAX_RAWSZ];
 		char *pack_tmp_name = NULL;
+		off_t pack_bytes;
 
 		if (pack_to_stdout) {
 			/*

@@ -1389,6 +1391,8 @@ static void write_pack_file(void)
 			display_progress(progress_state, written);
 		}
 
+		pack_bytes = hashfile_total(f) +
+			the_repository->hash_algo->rawsz;
 		if (pack_to_stdout) {
 			/*
 			 * We never fsync when writing to stdout since we may

@@ -1419,6 +1423,7 @@ static void write_pack_file(void)
 				write_bitmap_index = 0;
 			}
 		}
+		bytes_written += pack_bytes;