Hi, On Sun, Oct 2, 2011 at 8:29 PM, Arnaud Lacombe <lacom...@gmail.com> wrote: > Hi, > > On Sun, Oct 2, 2011 at 12:08 PM, Jack Vogel <jfvo...@gmail.com> wrote: >> On what hardware? >> > Only the 82574 is using em(4)'s MSI-X. > FWIW, I'm not seeing this issue on a 82574 box I've access to:
result of the following command: # ping -nqt 30 -f <ip> The two box are connected on an old 10/100 switch MSI-X enabled: 239361 packets transmitted, 239358 packets received, 0.0% packet loss round-trip min/avg/max/stddev = 0.090/0.117/2.488/0.027 ms MSI-X disabled: 233122 packets transmitted, 233119 packets received, 0.0% packet loss round-trip min/avg/max/stddev = 0.096/0.120/2.589/0.027 ms On another interface (same boxes involved, but through a 10/100/1000 switch): MSI-X enabled: 240080 packets transmitted, 240079 packets received, 0.0% packet loss round-trip min/avg/max/stddev = 0.090/0.116/0.175/0.008 ms MSI-X disabled: 207310 packets transmitted, 207309 packets received, 0.0% packet loss round-trip min/avg/max/stddev = 0.095/0.136/0.310/0.044 ms However, there seem to be a performance drop with MSI-X disabled and Gigabit link. - Arnaud >> 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" >> > _______________________________________________ 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"
