Seen on a RedHat-7.3 and a Debian-Woody system:

When running iftop-0.16, you can press "o" (letter o) to freeze the order. From that moment, the "total" column is counting much more than it should. Also the displayed bandwidth in the other columns is incorrect.

I hope you can reproduce it, if not I can give you access to one of the machines.

Richard.

/root/.iftoprc:

interface: eth0 dns-resolution: no port-resolution: no filter-code: not udp port 53 show-bars: yes promiscuous: yes port-display: on hide-source: no hide-destination: no use-bytes: no #sort: 2s #sort: 10s sort: 40s #sort: source #sort: destination line-display: one-line-both #line-display: two-line #line-display: one-line-sent #line-display: one-line-received show-totals: yes log-scale: no max-bandwidth: 2048k #net-filter: net/mask #screen-filter: regexp