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Message-ID: <53BD5D98.1030605@gmail.com> Date: Wed, 09 Jul 2014 11:19:52 -0400 From: Vlad Yasevich <vyasevich@...il.com> To: David Laight <David.Laight@...LAB.COM>, 'Daniel Borkmann' <dborkman@...hat.com> CC: "'davem@...emloft.net'" <davem@...emloft.net>, "'geirola@...il.com'" <geirola@...il.com>, "'netdev@...r.kernel.org'" <netdev@...r.kernel.org>, "'linux-sctp@...r.kernel.org'" <linux-sctp@...r.kernel.org> Subject: Re: [PATCH net-next 2/5] net: sctp: implement rfc6458, 5.3.4. SCTP_SNDINFO cmsg support On 07/09/2014 10:57 AM, David Laight wrote: >>> My 'other' test system in running 2.6.26 and probably sends multiple sacks >>> for packets containing a lot of data chunks. >>> >>> David >> >> That shouldn't happen even in 2.6.26. SACKs were always per packet, not per chunk > > There seem to be a lot of SACKs at the bottom of the trace below. > Maybe they are being sent as the application reads the data off the > socket, rather than directly in response to the received data. > Looks more of less correct if you correlate cum ack values to the data tsns. > tcpdump output edited to shorten the lines. > All the [SACK] have [#gap acks] [#dup tsns 0] > All the [DATA] have [PPIDx3] > A lot of earlier trace deleted, it all looks much the same. > > Trace taken on the sending system (dsl-a) running a 3.15(ish) kernel, > ss7-3 is runnin 2.6.18. > > 10:14:49.663034 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 622] [SID: 3] [SSEQ 2507] > 10:14:49.663038 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 623] [SID: 4] [SSEQ 2507] > 10:14:49.663040 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 624] [SID: 1] [SSEQ 2508] > 10:14:49.663041 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 625] [SID: 2] [SSEQ 2508] > 10:14:49.663043 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 626] [SID: 3] [SSEQ 2508] > 10:14:49.663044 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 627] [SID: 4] [SSEQ 2508] > 10:14:49.663045 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 628] [SID: 1] [SSEQ 2509] > 10:14:49.663118 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 629] [SID: 2] [SSEQ 2509] > 10:14:49.663123 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 630] [SID: 3] [SSEQ 2509] > 10:14:49.663125 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 631] [SID: 4] [SSEQ 2509] > 10:14:49.663126 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 632] [SID: 1] [SSEQ 2510] > 10:14:49.663173 ss7-3 > dsl-a: [SACK] [cum ack 568] [a_rwnd 62020] > 10:14:49.663189 ss7-3 > dsl-a: [SACK] [cum ack 570] [a_rwnd 62020] > 10:14:49.663197 ss7-3 > dsl-a: [SACK] [cum ack 572] [a_rwnd 61724] > 10:14:49.663210 ss7-3 > dsl-a: [SACK] [cum ack 574] [a_rwnd 61428] > 10:14:49.663217 ss7-3 > dsl-a: [SACK] [cum ack 576] [a_rwnd 61132] > 10:14:49.663229 ss7-3 > dsl-a: [SACK] [cum ack 578] [a_rwnd 60836] > 10:14:49.663246 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 633] [SID: 2] [SSEQ 2510] > 10:14:49.663250 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 634] [SID: 3] [SSEQ 2510] > 10:14:49.663251 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 635] [SID: 4] [SSEQ 2510] > 10:14:49.663252 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 636] [SID: 1] [SSEQ 2511] > 10:14:49.663254 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 637] [SID: 2] [SSEQ 2511] > 10:14:49.663255 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 638] [SID: 3] [SSEQ 2511] > 10:14:49.663257 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 639] [SID: 4] [SSEQ 2511] > 10:14:49.663305 ss7-3 > dsl-a: [SACK] [cum ack 579] [a_rwnd 62464] > 10:14:49.663331 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 640] [SID: 1] [SSEQ 2512] > 10:14:49.663335 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 641] [SID: 2] [SSEQ 2512] > 10:14:49.663336 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 642] [SID: 3] [SSEQ 2512] > 10:14:49.663337 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 643] [SID: 4] [SSEQ 2512] > 10:14:49.663435 ss7-3 > dsl-a: [SACK] [cum ack 581] [a_rwnd 62168] > 10:14:49.663447 ss7-3 > dsl-a: [SACK] [cum ack 583] [a_rwnd 61872] > 10:14:49.663454 ss7-3 > dsl-a: [SACK] [cum ack 585] [a_rwnd 61872] > 10:14:49.663465 ss7-3 > dsl-a: [SACK] [cum ack 587] [a_rwnd 61872] > 10:14:49.663473 ss7-3 > dsl-a: [SACK] [cum ack 589] [a_rwnd 61576] > 10:14:49.663485 ss7-3 > dsl-a: [SACK] [cum ack 591] [a_rwnd 61280] > 10:14:49.663498 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 644] [SID: 1] [SSEQ 2513] > 10:14:49.663505 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 645] [SID: 2] [SSEQ 2513] > 10:14:49.663507 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 646] [SID: 3] [SSEQ 2513] > 10:14:49.663510 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 647] [SID: 4] [SSEQ 2513] > 10:14:49.663512 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 648] [SID: 1] [SSEQ 2514] > 10:14:49.663514 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 649] [SID: 2] [SSEQ 2514] , > (2) [DATA] (B)(E) [TSN: 650] [SID: 3] [SSEQ 2514] , > (3) [DATA] (B)(E) [TSN: 651] [SID: 4] [SSEQ 2514] , > (4) [DATA] (B)(E) [TSN: 652] [SID: 1] [SSEQ 2515] > 10:14:49.663515 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 653] [SID: 2] [SSEQ 2515] , > (2) [DATA] (B)(E) [TSN: 654] [SID: 3] [SSEQ 2515] , > (3) [DATA] (B)(E) [TSN: 655] [SID: 4] [SSEQ 2515] , > (4) [DATA] (B)(E) [TSN: 656] [SID: 1] [SSEQ 2516] > 10:14:49.663517 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 657] [SID: 2] [SSEQ 2516] , > (2) [DATA] (B)(E) [TSN: 658] [SID: 3] [SSEQ 2516] , > (3) [DATA] (B)(E) [TSN: 659] [SID: 4] [SSEQ 2516] , > (4) [DATA] (B)(E) [TSN: 660] [SID: 1] [SSEQ 2517] > 10:14:49.663519 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 661] [SID: 2] [SSEQ 2517] , > (2) [DATA] (B)(E) [TSN: 662] [SID: 3] [SSEQ 2517] , > (3) [DATA] (B)(E) [TSN: 663] [SID: 4] [SSEQ 2517] , > (4) [DATA] (B)(E) [TSN: 664] [SID: 1] [SSEQ 2518] > 10:14:49.663523 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 665] [SID: 2] [SSEQ 2518] , > (2) [DATA] (B)(E) [TSN: 666] [SID: 3] [SSEQ 2518] , > (3) [DATA] (B)(E) [TSN: 667] [SID: 4] [SSEQ 2518] , > (4) [DATA] (B)(E) [TSN: 668] [SID: 1] [SSEQ 2519] > 10:14:49.663524 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 669] [SID: 2] [SSEQ 2519] , > (2) [DATA] (B)(E) [TSN: 670] [SID: 3] [SSEQ 2519] , > (3) [DATA] (B)(E) [TSN: 671] [SID: 4] [SSEQ 2519] , > (4) [DATA] (B)(E) [TSN: 672] [SID: 1] [SSEQ 2520] > 10:14:49.663627 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 673] [SID: 2] [SSEQ 2520] , > (2) [DATA] (B)(E) [TSN: 674] [SID: 3] [SSEQ 2520] , > (3) [DATA] (B)(E) [TSN: 675] [SID: 4] [SSEQ 2520] , > (4) [DATA] (B)(E) [TSN: 676] [SID: 1] [SSEQ 2521] > 10:14:49.663631 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 677] [SID: 2] [SSEQ 2521] , > (2) [DATA] (B)(E) [TSN: 678] [SID: 3] [SSEQ 2521] > 10:14:49.663632 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 679] [SID: 4] [SSEQ 2521] , > (2) [DATA] (B)(E) [TSN: 680] [SID: 1] [SSEQ 2522] , > (3) [DATA] (B)(E) [TSN: 681] [SID: 2] [SSEQ 2522] , > (4) [DATA] (B)(E) [TSN: 682] [SID: 3] [SSEQ 2522] > 10:14:49.663633 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 683] [SID: 4] [SSEQ 2522] , > (2) [DATA] (B)(E) [TSN: 684] [SID: 1] [SSEQ 2523] , > (3) [DATA] (B)(E) [TSN: 685] [SID: 2] [SSEQ 2523] , > (4) [DATA] (B)(E) [TSN: 686] [SID: 3] [SSEQ 2523] > 10:14:49.663634 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 687] [SID: 4] [SSEQ 2523] , > (2) [DATA] (B)(E) [TSN: 688] [SID: 1] [SSEQ 2524] , > (3) [DATA] (B)(E) [TSN: 689] [SID: 2] [SSEQ 2524] , > (4) [DATA] (B)(E) [TSN: 690] [SID: 3] [SSEQ 2524] > 10:14:49.663674 ss7-3 > dsl-a: [SACK] [cum ack 593] [a_rwnd 61280] > 10:14:49.663687 ss7-3 > dsl-a: [SACK] [cum ack 595] [a_rwnd 61280] > 10:14:49.663695 ss7-3 > dsl-a: [SACK] [cum ack 597] [a_rwnd 61280] > 10:14:49.663706 ss7-3 > dsl-a: [SACK] [cum ack 599] [a_rwnd 61280] > 10:14:49.663715 ss7-3 > dsl-a: [SACK] [cum ack 601] [a_rwnd 61132] > 10:14:49.663726 ss7-3 > dsl-a: [SACK] [cum ack 603] [a_rwnd 60836] > 10:14:49.663729 ss7-3 > dsl-a: [SACK] [cum ack 605] [a_rwnd 60540] > 10:14:49.663744 dsl-a > ss7-3: [DATA] (B)(E) [TSN: 691] [SID: 4] [SSEQ 2524] > 10:14:49.663834 ss7-3 > dsl-a: [SACK] [cum ack 606] [a_rwnd 62168] > 10:14:49.663928 ss7-3 > dsl-a: [SACK] [cum ack 608] [a_rwnd 62168] > 10:14:49.663939 ss7-3 > dsl-a: [SACK] [cum ack 610] [a_rwnd 62020] > 10:14:49.663946 ss7-3 > dsl-a: [SACK] [cum ack 612] [a_rwnd 61724] > 10:14:49.663957 ss7-3 > dsl-a: [SACK] [cum ack 614] [a_rwnd 61428] > 10:14:49.663964 ss7-3 > dsl-a: [SACK] [cum ack 616] [a_rwnd 61132] > 10:14:49.663976 ss7-3 > dsl-a: [SACK] [cum ack 618] [a_rwnd 61132] > 10:14:49.664183 ss7-3 > dsl-a: [SACK] [cum ack 620] [a_rwnd 61132] Don't see the data for the above so can't tell if they are right or not. > 10:14:49.664194 ss7-3 > dsl-a: [SACK] [cum ack 622] [a_rwnd 61132] > 10:14:49.664200 ss7-3 > dsl-a: [SACK] [cum ack 624] [a_rwnd 61132] > 10:14:49.664209 ss7-3 > dsl-a: [SACK] [cum ack 626] [a_rwnd 61132] > 10:14:49.664215 ss7-3 > dsl-a: [SACK] [cum ack 628] [a_rwnd 60984] > 10:14:49.664224 ss7-3 > dsl-a: [SACK] [cum ack 630] [a_rwnd 60688] > 10:14:49.664232 ss7-3 > dsl-a: [SACK] [cum ack 632] [a_rwnd 60392] > 10:14:49.664320 ss7-3 > dsl-a: [SACK] [cum ack 632] [a_rwnd 62020] > 10:14:49.664429 ss7-3 > dsl-a: [SACK] [cum ack 634] [a_rwnd 62020] > 10:14:49.664439 ss7-3 > dsl-a: [SACK] [cum ack 636] [a_rwnd 62020] > 10:14:49.664446 ss7-3 > dsl-a: [SACK] [cum ack 638] [a_rwnd 61724] > 10:14:49.664457 ss7-3 > dsl-a: [SACK] [cum ack 640] [a_rwnd 61428] > 10:14:49.664463 ss7-3 > dsl-a: [SACK] [cum ack 642] [a_rwnd 61132] > 10:14:49.664473 ss7-3 > dsl-a: [SACK] [cum ack 644] [a_rwnd 60836] > 10:14:49.664479 ss7-3 > dsl-a: [SACK] [cum ack 644] [a_rwnd 62464] > 10:14:49.664676 ss7-3 > dsl-a: [SACK] [cum ack 646] [a_rwnd 62168] > 10:14:49.664687 ss7-3 > dsl-a: [SACK] [cum ack 648] [a_rwnd 61872] All of the above chunks were send as individual packets so they are acked every 2 packets. > 10:14:49.664693 ss7-3 > dsl-a: [SACK] [cum ack 656] [a_rwnd 60688] > 10:14:49.664825 ss7-3 > dsl-a: [SACK] [cum ack 660] [a_rwnd 62316] > 10:14:49.664945 ss7-3 > dsl-a: [SACK] [cum ack 668] [a_rwnd 61280] > 10:14:49.664962 ss7-3 > dsl-a: [SACK] [cum ack 676] [a_rwnd 60096] > 10:14:49.664979 ss7-3 > dsl-a: [SACK] [cum ack 676] [a_rwnd 61724] > 10:14:49.665179 ss7-3 > dsl-a: [SACK] [cum ack 682] [a_rwnd 61724] > 10:14:49.665193 ss7-3 > dsl-a: [SACK] [cum ack 690] [a_rwnd 61724] > 10:14:49.864258 ss7-3 > dsl-a: [SACK] [cum ack 691] [a_rwnd 61724] Starting with TSN 649 you have bundling and the first two packets contains 649-656. Note the first cum ack is 656 in this block. If you look above, the SACKs are still for every other packet. There are a few repeats (like 2 sacks with cum ack 676 where a_rwnd grows). Those are just window update sacks. We did used to send window updates much more often then we do now. -vlad > > > > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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