On what hardware? Jack
On Sun, Oct 2, 2011 at 6:42 AM, Hooman Fazaeli <faza...@sepehrs.com> wrote: > > Latest em(4) driver from HEAD seems to have high latency > when MSIX is disabled. > > With MSIX enabled (hw.em.enable_msix=1): > > # ping -c5 192.168.1.83 > PING 192.168.1.83 (192.168.1.83): 56 data bytes > 64 bytes from 192.168.1.83: icmp_seq=0 ttl=64 time=0.055 ms > 64 bytes from 192.168.1.83: icmp_seq=1 ttl=64 time=0.076 ms > 64 bytes from 192.168.1.83: icmp_seq=2 ttl=64 time=0.066 ms > 64 bytes from 192.168.1.83: icmp_seq=3 ttl=64 time=0.051 ms > 64 bytes from 192.168.1.83: icmp_seq=4 ttl=64 time=0.063 ms > > --- 192.168.1.83 ping statistics --- > 5 packets transmitted, 5 packets received, 0.0% packet loss > round-trip min/avg/max/stddev = 0.051/0.062/0.076/0.009 ms > > With MSIX disabled: > > # ping -c5 192.168.1.83 > PING 192.168.1.83 (192.168.1.83): 56 data bytes > 64 bytes from 192.168.1.83: icmp_seq=0 ttl=64 time=0.180 ms > 64 bytes from 192.168.1.83: icmp_seq=1 ttl=64 time=0.164 ms > 64 bytes from 192.168.1.83: icmp_seq=2 ttl=64 time=0.169 ms > 64 bytes from 192.168.1.83: icmp_seq=3 ttl=64 time=0.172 ms > 64 bytes from 192.168.1.83: icmp_seq=4 ttl=64 time=0.167 ms > > --- 192.168.1.83 ping statistics --- > 5 packets transmitted, 5 packets received, 0.0% packet loss > round-trip min/avg/max/stddev = 0.164/0.170/0.180/0.005 ms > > As you see, w/o MSIX, RTT increases by a factor of 3. > > I also tested the following drivers: > - igb(4) from HEAD: OK. > - Stock 7.3-RELEASE: OK. > - Stock 7.4-RELEASE: problem exist. > > Any ideas? > > > > > _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
