It needs to get fixed.. let me generate a patch for you and you can test it.
> On Nov 5, 2015, at 8:51 AM, el...@sentor.se wrote: > > On Thu, 5 Nov 2015, Alexander V. Chernikov wrote: > >> >> >> 04.11.2015, 19:55, "el...@sentor.se" <el...@sentor.se>: >>> Hi! >>> >>> Question: >>> What do the Recv column in 'netstat -B' show? >>> >>> I thought it was tha amount of packets received, but appaently not so. >>> >>> I send 2000000 packets from a tcpreplay machine to a receiving machine. >>> I do it a few times. >>> >>> On the receiver I see: >>> netstat -in >>> Name Mtu Network Address Ipkts Ierrs Idrop Opkts >>> Oerrs Coll >>> ix0 1500 <Link#1> 0c:c4:7a:58:e2:3c 0 0 0 0 >>> 0 0 >>> ix1 1500 <Link#2> 0c:c4:7a:58:e2:3d 6000000 0 0 0 >>> 0 0 >>> >>> and then >>> netstat -in >>> Name Mtu Network Address Ipkts Ierrs Idrop Opkts >>> Oerrs Coll >>> ix0 1500 <Link#1> 0c:c4:7a:58:e2:3c 0 0 0 0 >>> 0 0 >>> ix1 1500 <Link#2> 0c:c4:7a:58:e2:3d 8000000 0 0 0 >>> 0 0 >>> >>> So 6000000 has increased to 8000000. Good. >>> >>> However, 'netstat -B' show: >>> Pid Netif Flags Recv Drop Match Sblen Hblen Command >>> 25553 mon0 p--s--- 1996862 0 2000000 0 0 tcpdump >>> >>> How can the "Recv" be *lower* than "Match"? >>> 1996862 < 2000000. >>> >>> For every new run (fast and slow) I get the same results, slightly less >>> than 2000000 Recv. >>> >>> What am I missing? >> Well, "Recv" is read from d->bd_rcount which is not per-cpu counter and is >> incrementing unlocked. >> On the other hand, "Match" increases when filter returned match condition >> and we (w)locked bpf descriptor, so this one is accurate. > > Ah. Thanks. > > > Will you make a bugzilla out of this? Or should I? Or is it not interesting > enough to fix? > > /Elof > _______________________________________________ > freebsd-net@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-net > To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org" _______________________________________________ freebsd-net@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
