I have a Dell server with four bonded, gigabit interfaces. Bonding mode is 802.3ad, xmit_hash_policy=layer3+4. When testing this setup with iperf, I never get more than a total of about 3Gbps throughput. Is there anything to tweak to get better throughput? Or am I running into other limits (e.g. was reading about tcp retransmit limits for mode 0).
The iperf test was run with iperf -s on the server, and iperf -c server on four clients connected to the same switch.
------------------------------------------------------------ Server listening on TCP port 5001 TCP window size: 85.3 KByte (default) ------------------------------------------------------------ [ 4] local 10.10.15.193 port 5001 connected with 10.10.15.184 port 48588 [ 5] local 10.10.15.193 port 5001 connected with 10.10.15.187 port 49231 [ 6] local 10.10.15.193 port 5001 connected with 10.10.15.188 port 53197 [ 7] local 10.10.15.193 port 5001 connected with 10.10.15.189 port 55309 [ ID] Interval Transfer Bandwidth [ 4] 0.0-10.0 sec 1.10 GBytes 941 Mbits/sec [ 5] 0.0-10.0 sec 872 MBytes 728 Mbits/sec [ 6] 0.0-10.0 sec 318 MBytes 267 Mbits/sec [ 7] 0.0-10.0 sec 1.10 GBytes 939 Mbits/sec [ 8] local 10.10.15.193 port 5001 connected with 10.10.15.184 port 48589 [ 4] local 10.10.15.193 port 5001 connected with 10.10.15.187 port 49234 [ 5] local 10.10.15.193 port 5001 connected with 10.10.15.188 port 38864 [ 6] local 10.10.15.193 port 5001 connected with 10.10.15.189 port 55311 [ 8] 0.0-10.0 sec 1.10 GBytes 941 Mbits/sec [ 4] 0.0-10.0 sec 862 MBytes 721 Mbits/sec [ 5] 0.0-10.0 sec 322 MBytes 270 Mbits/sec [ 6] 0.0-10.0 sec 1.10 GBytes 939 Mbits/sec
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