On Wed, Jun 20, 2007 at 09:24:16PM -0400, Arnaud Bergeron wrote: > I have a problem where I need to know how much traffic has passed on a > given interface. I don't need it broken down by IPs, protocols or > whatever of the sort. > > After a bit of research I discovered the SIOCGIFDATA ioctl that seems > to do what I want. > > I built myself a little test application to try it out (see at the end > of the mail for the code). The number it reports for my egress > interface are weird though: > > $ ./ifbw pppoe0 > bandwidth: 802865637b up 1907983523b down > reduced: 765.67MiB up 1.78GiB down > > I am certain I downloaded at least 2.6GB in the last few days and > uploaded at least 3.2GB. Also, for the outbound traffic shaping queue > I have over this interface pftop reports 33Gb of traffic. > > So I have questions for the network gurus. Am I doing something > incorrectly with my code below? > If not, are the counters just out of whack and it's normal? > > Also, if anybody knows a better way to do this, please tell me. >
The if_data counters are defined as u_long which wrap at around 4.5GB. You need to use your own absolute counter and poll if_data from time to time. Switching to 64bit counters is not trivial but it will happen. -- :wq Claudio
