From 49bee717f7080f99d3405682cc43ad525dde0973 Mon Sep 17 00:00:00 2001 From: "Shawn O. Pearce" Date: Mon, 14 Mar 2011 16:48:39 -0700 Subject: upload-pack: More aggressively send 'ACK %s ready' If a client is merely following the remote (and has not made any new commits itself), all "have %s" lines sent by the client will be common to the server. As all lines are common upload-pack never calls ok_to_give_up() and does not compute if it has a good cut point in the commit graph. Without this computation the following client is going to send all tagged commits, as these were determined to be COMMON_REF during the initial advertisement, but the client does not parse their history to transitively pass the COMMON flag and empty its queue of commits. For git.git with 339 commit tags, it takes clients 11 rounds of negotation to fully send all tagged commits and exhaust its queue of things to send as common. This is pretty slow for a client that has not done any local development activity. Force computing ok_to_give_up() and send "ACK %s ready" at the end of the current round if this round only contained common objects and ok_to_give_up() was therefore not called. This may allow the client to break early, avoiding transmission of the COMMON_REFs. Signed-off-by: Shawn O. Pearce Signed-off-by: Junio C Hamano --- upload-pack.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'upload-pack.c') diff --git a/upload-pack.c b/upload-pack.c index b40a43f27d..11c3849a79 100644 --- a/upload-pack.c +++ b/upload-pack.c @@ -429,6 +429,8 @@ static int get_common_commits(void) static char line[1000]; unsigned char sha1[20]; char last_hex[41]; + int got_common = 0; + int got_other = 0; save_commit_buffer = 0; @@ -437,16 +439,22 @@ static int get_common_commits(void) reset_timeout(); if (!len) { + if (multi_ack == 2 && got_common + && !got_other && ok_to_give_up()) + packet_write(1, "ACK %s ready\n", last_hex); if (have_obj.nr == 0 || multi_ack) packet_write(1, "NAK\n"); if (stateless_rpc) exit(0); + got_common = 0; + got_other = 0; continue; } strip(line, len); if (!prefixcmp(line, "have ")) { switch (got_sha1(line+5, sha1)) { case -1: /* they have what we do not */ + got_other = 1; if (multi_ack && ok_to_give_up()) { const char *hex = sha1_to_hex(sha1); if (multi_ack == 2) @@ -456,6 +464,7 @@ static int get_common_commits(void) } break; default: + got_common = 1; memcpy(last_hex, sha1_to_hex(sha1), 41); if (multi_ack == 2) packet_write(1, "ACK %s common\n", last_hex); -- cgit v1.2.3 From 3e63b21aced116badd30a279c479535449a63560 Mon Sep 17 00:00:00 2001 From: "Shawn O. Pearce" Date: Mon, 14 Mar 2011 17:59:40 -0700 Subject: upload-pack: Implement no-done capability If the client requests both multi_ack_detailed and no-done then upload-pack is free to immediately send a PACK following its first 'ACK %s ready' message. The upload-pack response actually winds up being: ACK %s common ... (maybe more) ... ACK %s ready NAK ACK %s PACK.... the pack stream .... For smart HTTP connections this saves one HTTP RPC, reducing the overall latency for a trivial fetch. For git:// and ssh:// a no-done option slightly reduces latency by removing one server->client->server round-trip at the end of the common ancestor negotiation. Signed-off-by: Shawn O. Pearce Signed-off-by: Junio C Hamano --- upload-pack.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) (limited to 'upload-pack.c') diff --git a/upload-pack.c b/upload-pack.c index 11c3849a79..5924f6f988 100644 --- a/upload-pack.c +++ b/upload-pack.c @@ -27,6 +27,7 @@ static const char upload_pack_usage[] = "git upload-pack [--strict] [--timeout=< static unsigned long oldest_have; static int multi_ack, nr_our_refs; +static int no_done; static int use_thin_pack, use_ofs_delta, use_include_tag; static int no_progress, daemon_mode; static int shallow_nr; @@ -431,6 +432,7 @@ static int get_common_commits(void) char last_hex[41]; int got_common = 0; int got_other = 0; + int sent_ready = 0; save_commit_buffer = 0; @@ -440,10 +442,17 @@ static int get_common_commits(void) if (!len) { if (multi_ack == 2 && got_common - && !got_other && ok_to_give_up()) + && !got_other && ok_to_give_up()) { + sent_ready = 1; packet_write(1, "ACK %s ready\n", last_hex); + } if (have_obj.nr == 0 || multi_ack) packet_write(1, "NAK\n"); + + if (no_done && sent_ready) { + packet_write(1, "ACK %s\n", last_hex); + return 0; + } if (stateless_rpc) exit(0); got_common = 0; @@ -457,9 +466,10 @@ static int get_common_commits(void) got_other = 1; if (multi_ack && ok_to_give_up()) { const char *hex = sha1_to_hex(sha1); - if (multi_ack == 2) + if (multi_ack == 2) { + sent_ready = 1; packet_write(1, "ACK %s ready\n", hex); - else + } else packet_write(1, "ACK %s continue\n", hex); } break; @@ -535,6 +545,8 @@ static void receive_needs(void) multi_ack = 2; else if (strstr(line+45, "multi_ack")) multi_ack = 1; + if (strstr(line+45, "no-done")) + no_done = 1; if (strstr(line+45, "thin-pack")) use_thin_pack = 1; if (strstr(line+45, "ofs-delta")) @@ -628,7 +640,7 @@ static int send_ref(const char *refname, const unsigned char *sha1, int flag, vo { static const char *capabilities = "multi_ack thin-pack side-band" " side-band-64k ofs-delta shallow no-progress" - " include-tag multi_ack_detailed"; + " include-tag multi_ack_detailed no-done"; struct object *o = parse_object(sha1); if (!o) -- cgit v1.2.3