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 ?
> > _______________________________________________
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