tcprstat hangs with 100% cpu load

[Uli Stärk]

# uname -a
Linux hostname 2.6.18.xs4.0.1.900.5799 #2 SMP Mon Aug 13 13:56:47 UTC 2007 i686 GNU/Linux

I start tcprstat with the following command line:
./tcprstat-static -t 1 -n 0 -p 80

As long as no traffic is captured, everything works fine. But when I do a couple of clicks, the program hangs and uses 100% cpu time on one core.

timestamp count max min avg med stddev 95_max 95_avg 95_std 99_max 99_avg 99_std
1283356401 0 0 0 0 0 0 0 0 0 0 0 0
1283356402 0 0 0 0 0 0 0 0 0 0 0 0
1283356403 0 0 0 0 0 0 0 0 0 0 0 0
*hangs*

If you press CTRL+C a final line gets flushed - up to the stddev column (excluded):
1283356404 7 301574 546 44728 672

This is reproducable every time.

[wesam80 (wesamd)]

Any solution plz?

[Baron Schwartz (baron-xaprb)]

I can reproduce this. I hope that someone can contribute a patch to
solve it, because it isn't affecting any of my customers so they
aren't interested in paying for a fix.

[Alex Samorukov (samm-os2)]

I found a bug. it hanging in sqrt function (endless loop), which is tricky and processor depended. I switched to the OS one and it works for me. Please try my patch.

[Baron Schwartz (baron-xaprb)]

Great, thank you for finding the problem. I think it is a good idea
to use standard math.h functions when we can, so we should use your
patch.