我有四个虚拟机，其中两个连接在一起。VM1 和 VM2 已连接，VM3 和 VM4 已连接。
我使用 iperf3 来测试吞吐量。
VM1 和 VM2 统计数据正常，但 VM3 和 VM4 统计数据会突然出现吞吐量下降。如何找到根本原因并调整网络吞吐量？
下面是 VM1 TX 和 VM3 TX 上的 iperf3 吞吐量统计。
我的问题是为什么 VM3（471Mbps->198Mbps）会出现抖动或吞吐量突然下降，但是在 VM1 上，吞吐量是稳定的。
请注意，四个虚拟机之间的所有配置都是相同的。它应该有相同的结果。
VM1 和 VM2：
VM1 上的命令：
iperf3 -c 10.10.10.158 -u -B 10.10.10.157 -tinf -l 1472 -b 1000M
VM2 上的命令：
iperf3 -s -u -B 10.10.10.158
VM1 TX 上的 iperf 结果：
[ ID] Interval Transfer Bitrate Total Datagrams
[ 6] 30.00-31.00 sec 56.1 MBytes 470 Mbits/sec 39944
[ 6] 31.00-32.00 sec 54.2 MBytes 454 Mbits/sec 38594
[ 6] 32.00-33.00 sec 54.6 MBytes 458 Mbits/sec 38862
[ 6] 33.00-34.00 sec 56.0 MBytes 470 Mbits/sec 39877
[ 6] 34.00-35.00 sec 56.1 MBytes 471 Mbits/sec 39973
[ 6] 35.00-36.00 sec 55.8 MBytes 468 Mbits/sec 39783
[ 6] 36.00-37.00 sec 56.7 MBytes 476 Mbits/sec 40419
[ 6] 37.00-38.00 sec 56.2 MBytes 472 Mbits/sec 40052
[ 6] 38.00-39.00 sec 56.2 MBytes 471 Mbits/sec 40014
[ 6] 39.00-40.00 sec 55.9 MBytes 469 Mbits/sec 39796
[ 6] 40.00-41.00 sec 56.0 MBytes 469 Mbits/sec 39868
[ 6] 41.00-42.00 sec 56.0 MBytes 470 Mbits/sec 39894
[ 6] 42.00-43.00 sec 56.8 MBytes 477 Mbits/sec 40488
[ 6] 43.00-44.00 sec 56.4 MBytes 473 Mbits/sec 40196
[ 6] 44.00-45.00 sec 56.8 MBytes 477 Mbits/sec 40496
[ 6] 45.00-46.00 sec 56.1 MBytes 471 Mbits/sec 39987
[ 6] 46.00-47.00 sec 56.4 MBytes 473 Mbits/sec 40141
[ 6] 47.00-48.00 sec 55.4 MBytes 465 Mbits/sec 39492
[ 6] 48.00-49.00 sec 56.8 MBytes 476 Mbits/sec 40427
[ 6] 49.00-50.00 sec 56.3 MBytes 472 Mbits/sec 40112
[ 6] 50.00-51.00 sec 56.7 MBytes 476 Mbits/sec 40386
[ 6] 51.00-52.00 sec 56.6 MBytes 475 Mbits/sec 40303
[ 6] 52.00-53.00 sec 55.8 MBytes 468 Mbits/sec 39762
[ 6] 53.00-54.00 sec 56.5 MBytes 474 Mbits/sec 40251
[ 6] 54.00-55.00 sec 56.2 MBytes 471 Mbits/sec 40017
[ 6] 55.00-56.00 sec 55.6 MBytes 466 Mbits/sec 39603
[ 6] 56.00-57.00 sec 56.7 MBytes 476 Mbits/sec 40388
VM3 和 VM4：
VM3 上的命令：
iperf3 -c 10.10.10.222 -u -B 10.10.10.221 -tinf -l 1472 -b 1000M
VM4 上的命令：
iperf3 -s -u -B 10.10.10.222
VM3 TX 上的 iperf3 结果
[ ID] Interval Transfer Bitrate Total Datagrams
[ 6] 200.00-201.00 sec 55.6 MBytes 467 Mbits/sec 39622
[ 6] 201.00-202.00 sec 56.0 MBytes 470 Mbits/sec 39915
[ 6] 202.00-203.00 sec 55.7 MBytes 467 Mbits/sec 39655
[ 6] 203.00-204.00 sec 51.7 MBytes 434 Mbits/sec 36851
[ 6] 204.00-205.00 sec 24.5 MBytes 206 Mbits/sec 17483
[ 6] 205.00-206.00 sec 23.9 MBytes 201 Mbits/sec 17060
[ 6] 206.00-207.00 sec 23.4 MBytes 196 Mbits/sec 16680
[ 6] 207.00-208.00 sec 23.7 MBytes 199 Mbits/sec 16890
[ 6] 208.00-209.00 sec 23.6 MBytes 198 Mbits/sec 16836
[ 6] 209.00-210.00 sec 23.1 MBytes 194 Mbits/sec 16486
[ 6] 210.00-211.00 sec 23.6 MBytes 198 Mbits/sec 16824
[ 6] 211.00-212.00 sec 23.7 MBytes 199 Mbits/sec 16884
[ 6] 212.00-213.00 sec 23.2 MBytes 194 Mbits/sec 16506