| // SPDX-License-Identifier: GPL-2.0 |
| // Test of slow start after idle |
| // This test expects tso size to be at least initial cwnd * mss |
| |
| `./defaults.sh |
| ./set_sysctls.py /proc/sys/net/ipv4/tcp_slow_start_after_idle=1 \ |
| /proc/sys/net/ipv4/tcp_min_tso_segs=10` |
| |
| 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 65535 <mss 1000,sackOK,nop,nop,nop,wscale 7> |
| +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8> |
| +.1 < . 1:1(0) ack 1 win 511 |
| +0 accept(3, ..., ...) = 4 |
| +0 setsockopt(4, SOL_SOCKET, SO_SNDBUF, [200000], 4) = 0 |
| |
| +0 write(4, ..., 26000) = 26000 |
| +0 > P. 1:5001(5000) ack 1 |
| +0 > P. 5001:10001(5000) ack 1 |
| +0 %{ assert tcpi_snd_cwnd == 10, tcpi_snd_cwnd }% |
| |
| +.1 < . 1:1(0) ack 10001 win 511 |
| +0 %{ assert tcpi_snd_cwnd == 20, tcpi_snd_cwnd }% |
| +0 > P. 10001:20001(10000) ack 1 |
| +0 > P. 20001:26001(6000) ack 1 |
| |
| +.1 < . 1:1(0) ack 26001 win 511 |
| +0 %{ assert tcpi_snd_cwnd == 36, tcpi_snd_cwnd }% |
| |
| +2 write(4, ..., 20000) = 20000 |
| // If slow start after idle works properly, we should send 5 MSS here (cwnd/2) |
| +0 > P. 26001:31001(5000) ack 1 |
| +0 %{ assert tcpi_snd_cwnd == 10, tcpi_snd_cwnd }% |
| |
| // Reset sysctls |
| `/tmp/sysctl_restore_${PPID}.sh` |
