| // SPDX-License-Identifier: GPL-2.0 |
| // Test of slow start when an outstanding flight of packets is |
| // less than the current cwnd, but still big enough that in slow |
| // start we want to increase our cwnd a little. |
| // |
| // In this variant, the receiver ACKs every other packet, |
| // approximating standard delayed ACKs. |
| |
| // Set up config. |
| `./defaults.sh` |
| |
| 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 |
| +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 |
| +0 bind(3, ..., ...) = 0 |
| +0 listen(3, 1) = 0 |
| |
| +0 < S 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 7> |
| +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8> |
| +0 < . 1:1(0) ack 1 win 257 |
| +0 accept(3, ..., ...) = 4 |
| |
| // Only send 6 packets. |
| +0 write(4, ..., 6000) = 6000 |
| +0 > P. 1:6001(6000) ack 1 |
| +0 %{ assert tcpi_snd_cwnd == 10, tcpi_snd_cwnd }% |
| |
| +0 < . 1:1(0) ack 2001 win 257 |
| +0 %{ assert tcpi_snd_cwnd == 12, 'cwnd=%d' % tcpi_snd_cwnd }% |
| |
| +0 < . 1:1(0) ack 4001 win 257 |
| +0 %{ assert tcpi_snd_cwnd == 12, 'cwnd=%d' % tcpi_snd_cwnd }% |
| |
| +0 < . 1:1(0) ack 6001 win 257 |
| +0 %{ assert tcpi_snd_cwnd == 12, 'cwnd=%d' % tcpi_snd_cwnd }% |
