Stephen Hemminger <stephen at networkplumber.org> wrote: > Your excess polling consumes PCI bandwidth which is a fixed resource.
I doubt that this is the problem for three reasons: * The poll rate would regulate itself if the PCIe bus was the bottleneck * This problem only occurs with 82599 chips, not with X540 chips (which are virtually identical except for 10GBase-T vs. fiber) * This effect already appears with relatively low poll rates (batch size 1). The overhead would have to be > 128 bytes per poll to saturate the PCIe bus at this rate. (Even if this was the case, my first point still applies) I unfortunately don't have a test system with a CPU that supports PCIe performance counters with a 82599 card. Otherwise I'd measure this since I think this effect is really interesting (I'm a co-authors of the paper linked above). Paul
