Hello,
I am seeing strange behavior recently in iftop on Ubuntu (x64, 12.04 and
13.10). With Port Display disabled, iftop simply uses more CPU than
normal (say, 20% instead of a negligible amount). Then, when Port
Display is enabled, CPU use goes straight to 100% and iftop becomes
unresponsive.
This behavior started sometime in the last few months, and occurs on 2
of the 4 Ubuntu machines that I've tested it on. I compiled iftop 0.17
and 1.0-pre2 from source and observed the same behavior as the
precompiled version (1.0-pre2 from the Ubuntu repo) on these computers.
I cannot figure out what is unique (other than physical hardware) about
the 2 machines that still work, except that they use 3.2 and 3.6 kernels
(vs. 3.5 and 3.11 on the machines that don't work). So maybe there's a
network driver issue? I checked the version numbers of libc6,
libncurses, libpcap, and libtinfo (all the dependencies I know of) and
they are the same on 1 of the working machines vs. 1 of the non-working
ones. And iftop worked properly on all of these machines until some
relatively recent update.
So, iftop is completely unusable on at least 2 of my computers. Can
anyone recommend further troubleshooting steps that I could take to
isolate this problem, preferably without rebooting? Are there any other
library versions I should check?
Thanks,
Alex
