Hi are you setting the flush flag to 1 when calling pfring_send()? Alfredo
> On 26 Oct 2017, at 18:42, Charles-Antoine Mathieu > <[email protected]> wrote: > > Hi, > > I'm trying to implement that, but my results looks odd. I'm trying to > ping a bunch of ~20 hosts with a latency of ~1.77 ms every 5 seconds. > > I capture time right after pfring_send and pfring_recv. For every batch > I get around the same latency for every host but the latency range from > 1ms to 300ms. > > 37.187.9.32 : 11.532119ms > 37.187.9.245 : 11.54512ms > 37.187.9.124 : 11.525933ms > ... 5 sec later the next batch ... > 37.187.9.14 : 107.540483ms > 37.187.9.17 : 107.519064ms > 37.187.9.32 : 107.505375ms > > I wonder if you are aware of some kind of buffering that might happen > in the process to yield such results. > > The ring is opened in ZC mode > NIC model is Intel Corporation 82599ES 10-Gigabit SFI/SFP+ Network > Connection (rev 01) > > I'm using gopacket and ARISTA's nanotime package to capture a monotonic > time which rely upon CLOCK_MONOTONIC, it seems more reliable and > lightweight that time.Now() to me. > https://github.com/aristanetworks/goarista/blob/master/monotime/nanotim > e.go > > On Fri, 2017-10-06 at 16:38 +0200, Alfredo Cardigliano wrote: >> Hi >> in ZC mode kernel is bypassed, thus you should send the packet and >> call clock_gettime() >> immediately after in order to compute latency (the same function is >> used for RX in this case). >> >> Alfredo >> >>> >>> On 6 Oct 2017, at 16:34, Charles-Antoine Mathieu <charles-antoine.m >>> [email protected]> wrote: >>> >>> Hello, >>> >>> I have a process that sends and receive ICMP packets using PF_RING. >>> >>> I'd like to capture send and received packets to be able to compute >>> the >>> latency. When I'm not in ZC mode I get the send and the received >>> packet >>> in the capture. However in ZC mode I only get the received packets >>> in >>> the capture. >>> >>> Is there a way go get the same behaviour in ZC mode ? >>> _______________________________________________ >>> Ntop mailing list >>> [email protected] >>> http://listgateway.unipi.it/mailman/listinfo/ntop >> _______________________________________________ >> Ntop mailing list >> [email protected] >> http://listgateway.unipi.it/mailman/listinfo/ntop > _______________________________________________ > Ntop mailing list > [email protected] > http://listgateway.unipi.it/mailman/listinfo/ntop
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