From a quick look at the vlan code, I can identify a few cases that might cause that counter to increment:
1) Error from the underlying ixgbe device. Does "netstat -dI ix0" show that the driver has been dropping packets? 2) Link down events on the underlying NIC. I believe that link flaps will be logged to /var/log/messages and dmesg; do you see anything there that might correspond to the time of the packet drops? 3) If VLAN_HWTAGGING is disabled through ifconfig on the port, then in theory a low memory event could cause the packet to be dropped. Does "netstat -m" show that "requests for mbufs denied" increasing? On Wed, Apr 27, 2016 at 2:41 PM, Zé Claudio Pastore <zclau...@bsd.com.br> wrote: > Hello, > > On a BGP border router I help manage, we run FreeBSD 10.1-STABLE, > version r281235 and it works fine for several years now. > > We have around 4Gbit/s and 1.8Mpps routed on peak while per port interface > we peak at 300Kpps. > > Our quality metrics are measured with: > > ping -s 1472 -i 0.1 <our-other-ibgp-router> > > As well as iperf bidirecional. > > This metric is similar to what Speedy Test and SIMET tests are done and our > customers reference. > > Systems working w/o problem: > - 10.1-STABLE / r281235 > > Systems tested with drops: > - 10.2-STABLE / r292035M > - 10.3-STABLE / r298705 > - 11.0-CURRENT / r295683 (downloaded snapshot from ftp.freebsd.org) > - 11.0-CURRENT Melifaro Routing Branch / r297731M > > While testing, when errors happen I can see output errs on the vlan port on > the output from "netstat -w1 -I vlan6" > > input vlan6 output > packets errs idrops bytes packets errs bytes colls > 1 0 0 66 30557 2 33310968 0 > 1 0 0 105 31458 3 33912219 0 > 2 0 0 2954 32001 8 34983986 0 > 1 0 0 1512 33150 6 35942558 0 > 1 0 0 1512 33654 4 37311862 0 > 1 0 0 1512 34825 3 38213793 0 > 3 0 0 1683 35376 4 39488912 0 > 5 0 0 7280 32423 3 35551869 0 > > Problems may happen under high load (~200Kpps) or low load (~30Kpps) on a > vlan port. The observed frame loss never happens on untagged ports, only > vlan related. The observed loss happens with packets sized 900 bytes and > above but noticeably loss rate is higher with packets close to 1400 (1472 > is my reference size). > > Loss rate on all listed systems different from r281235 is 9-19% with > ping(1) and iperf, while it's 0% on r281235. > > First I believed it to be a Intel driver error on systems newer than 10.1. > My reference card are dual port 82599EB 10-Gigabit SFI/SFP+ Network > Connection (2x2 on x8 PCIe bus, total 4x10G). But yesterday I replaced > Intel by Chelsio T5 and the problem is still exactly the same, so it's not > related to card vendor. > > I always test the very same hardware, I have two SSD drives in this router, > one for the 10.1 which just runs fine and the other disk to test the > various versions of FreeBSD. > > Only minor loader and sysctl confs are tweaked: > > kern.hz=2000 > net.inet.ip.redirect=1 # do not send IP redirects > net.inet.ip.accept_sourceroute=0 # drop source routed packets since > they ca > net.inet.ip.sourceroute=0 # if source routed packets are > accepted th > net.inet.tcp.drop_synfin=1 # SYN/FIN packets get dropped on > initial c > net.inet.udp.blackhole=1 # drop udp packets destined for > closed soc > net.inet.tcp.blackhole=2 # drop tcp packets destined for > closed por > security.bsd.see_other_uids=0 > > Can anyone suggest what might be a fix/tuning for this behavior? Was there > any relevant change on vlan code from particular revisions close to the one > I run on 10.1 and later which would lead to such a big difference? > _______________________________________________ > 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"
