Robert, Please review and consider this patch to iperf to fix the segfault. Looks like in function byte_snprintf() when calculating SUM, where SUM is in terabyte, we go past the kLabel_Byte/kLabel_bit array limit (by increment of conv past kConv_Giga) and this causes iperf to segfault because suffix is pointing past the array bounds. The attached patch addresses this issue. -- Before patch -- $ iperf -c 192.168.120.2 -P10 -w 130k -t 1200 ------------------------------------------------------------ Client connecting to 192.168.120.2, TCP port 5001 TCP window size: 254 KByte (WARNING: requested 127 KByte) ------------------------------------------------------------ [ 12] local 192.168.120.3 port 47668 connected with 192.168.120.2 port 5001 [ 10] local 192.168.120.3 port 47664 connected with 192.168.120.2 port 5001 [ 11] local 192.168.120.3 port 47666 connected with 192.168.120.2 port 5001 [ 8] local 192.168.120.3 port 47662 connected with 192.168.120.2 port 5001 [ 5] local 192.168.120.3 port 47656 connected with 192.168.120.2 port 5001 [ 4] local 192.168.120.3 port 47650 connected with 192.168.120.2 port 5001 [ 6] local 192.168.120.3 port 47654 connected with 192.168.120.2 port 5001 [ 9] local 192.168.120.3 port 47660 connected with 192.168.120.2 port 5001 [ 7] local 192.168.120.3 port 47658 connected with 192.168.120.2 port 5001 [ 3] local 192.168.120.3 port 47652 connected with 192.168.120.2 port 5001 [ ID] Interval Transfer Bandwidth [ 12] 0.0-1200.0 sec 73.3 GBytes 525 Mbits/sec [ 10] 0.0-1200.0 sec 164 GBytes 1.17 Gbits/sec [ 11] 0.0-1200.0 sec 219 GBytes 1.57 Gbits/sec [ 8] 0.0-1200.0 sec 73.3 GBytes 525 Mbits/sec [ 5] 0.0-1200.0 sec 164 GBytes 1.18 Gbits/sec [ 4] 0.0-1200.0 sec 165 GBytes 1.18 Gbits/sec [ 6] 0.0-1200.0 sec 109 GBytes 784 Mbits/sec [ 9] 0.0-1200.0 sec 165 GBytes 1.18 Gbits/sec [ 7] 0.0-1200.0 sec 109 GBytes 783 Mbits/sec [ 3] 0.0-1200.0 sec 73.3 GBytes 525 Mbits/sec Segmentation fault (core dumped) -- After patch -- $ src/iperf -c 192.168.120.2 -P10 -w 130k -t 1200 ------------------------------------------------------------ Client connecting to 192.168.120.2, TCP port 5001 TCP window size: 254 KByte (WARNING: requested 127 KByte) ------------------------------------------------------------ [ 12] local 192.168.120.3 port 47626 connected with 192.168.120.2 port 5001 [ 8] local 192.168.120.3 port 47616 connected with 192.168.120.2 port 5001 [ 10] local 192.168.120.3 port 47622 connected with 192.168.120.2 port 5001 [ 3] local 192.168.120.3 port 47610 connected with 192.168.120.2 port 5001 [ 9] local 192.168.120.3 port 47620 connected with 192.168.120.2 port 5001 [ 4] local 192.168.120.3 port 47608 connected with 192.168.120.2 port 5001 [ 7] local 192.168.120.3 port 47614 connected with 192.168.120.2 port 5001 [ 11] local 192.168.120.3 port 47624 connected with 192.168.120.2 port 5001 [ 5] local 192.168.120.3 port 47612 connected with 192.168.120.2 port 5001 [ 6] local 192.168.120.3 port 47618 connected with 192.168.120.2 port 5001 [ ID] Interval Transfer Bandwidth [ 3] 0.0-1200.0 sec 142 GBytes 1.02 Gbits/sec [ 9] 0.0-1200.0 sec 120 GBytes 862 Mbits/sec [ 11] 0.0-1200.0 sec 121 GBytes 867 Mbits/sec [ 5] 0.0-1200.0 sec 122 GBytes 874 Mbits/sec [ 12] 0.0-1200.0 sec 120 GBytes 856 Mbits/sec [ 8] 0.0-1200.0 sec 122 GBytes 871 Mbits/sec [ 10] 0.0-1200.0 sec 146 GBytes 1.04 Gbits/sec [ 4] 0.0-1200.0 sec 141 GBytes 1.01 Gbits/sec [ 7] 0.0-1200.0 sec 122 GBytes 873 Mbits/sec [ 6] 0.0-1200.0 sec 143 GBytes 1.02 Gbits/sec [SUM] 0.0-1200.0 sec 1299 GBytes 9.30 Gbits/sec