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1// SPDX-License-Identifier: GPL-2.02// Test of slow start when not application-limited, so that3// the cwnd continues to grow.4// In this variant, the receiver sends one ACK per 4 packets.5 6// Set up config. To keep things simple, disable the7// mechanism that defers sending in order to send bigger TSO packets.8`./defaults.sh9sysctl -q net.ipv4.tcp_tso_win_divisor=100`10 11 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 312 +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 013 +0 bind(3, ..., ...) = 014 +0 listen(3, 1) = 015 16 +.1 < S 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 7>17 +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>18 +.1 < . 1:1(0) ack 1 win 25719 +0 accept(3, ..., ...) = 420 +0 setsockopt(4, SOL_SOCKET, SO_SNDBUF, [200000], 4) = 021 22 +0 write(4, ..., 30000) = 3000023 +0 > P. 1:10001(10000) ack 124 +0 %{ assert tcpi_snd_cwnd == 10, tcpi_snd_cwnd }%25 26 +.11 < . 1:1(0) ack 4001 win 25727 +0 > P. 10001:18001(8000) ack 128 29 +.01 < . 1:1(0) ack 8001 win 25730 +0 > P. 18001:26001(8000) ack 131 32+.005 < . 1:1(0) ack 10001 win 25733 +0 > P. 26001:30001(4000) ack 134 35 +0 %{ assert tcpi_snd_cwnd == 20, tcpi_snd_cwnd }%36