On Fri, 28 Oct 2005 21:33:39 +0000 "Josh Burke" <kernelbridgeissue@xxxxxxxxx> wrote: > (originally filed as a bug in Fedora's bugzilla, see https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=171933) > > Greetings, > > Using Fedora Core 4 on a Dell PE 420sc. Malfunctioning kernel is smp-2.6.13-1.1532_FC4. Properly functioning kernels included smp-2.6.12-1.1456_FC4. > > Network performance is extremely poor when using bridged network interfaces. When not using brctl, the interface gives ~800kbps. When using brctl to bridge two interfaces, the speed drops to ~1.0kbps. > > Reverting to kernel-smp-2.6.12-1.1456_FC4 returns the speed to normal. > > The two interfaces have IP addresses when not bridged. They do not have IP addresses when they are bridged. (As expected.) > > No unusual output in dmesg. > > Traffic is not slowed that originates on a bridge interfaces and goes out a bridge interface, only traffic from the host that the bridge is on, is slowed. > > Making these connections unbridged returns normal traffic performance. Reverting to 2.6.12 also returns normal performance. > > Tcpdump indicates increasing pauses returning packets. (From bridge host to the outside. Bridge host is a web server, though even SSH connections are slow.) > > For example: > 14:25:53.387001 IP 192.168.0.1.https > 10.0.0.1.32752: tcp 1260 > 14:25:53.648768 IP 10.0.0.1.32752 > 192.168.0.1.https: tcp 0 > 14:25:53.648817 IP 192.168.0.1.https > 10.0.0.1.32752: tcp 1260 > 14:25:53.648859 IP 192.168.0.1.https > 10.0.0.1.32752: tcp 1260 > 14:25:53.770239 IP 10.0.0.1.32752 > 192.168.0.1.https: tcp 0 > 14:26:03.242674 IP 192.168.0.1.https > 10.0.0.1.32752: tcp 1260 > 14:26:03.462594 IP 10.0.0.1.32752 > 192.168.0.1.https: tcp 0 > 14:26:03.462675 IP 192.168.0.1.https > 10.0.0.1.32752: tcp 1260 > 14:26:03.462714 IP 192.168.0.1.https > 10.0.0.1.32752: tcp 1260 > 14:26:03.581169 IP 10.0.0.1.32752 > 192.168.0.1.https: tcp 0 > 14:26:22.526025 IP 192.168.0.1.https > 10.0.0.1.32752: tcp 1260 > 14:26:22.784218 IP 10.0.0.1.32752 > 192.168.0.1.https: tcp 0 > 14:26:22.784325 IP 192.168.0.1.https > 10.0.0.1.32752: tcp 1260 > 14:26:22.784379 IP 192.168.0.1.https > 10.0.0.1.32752: tcp 1260 > 14:26:22.895638 IP 10.0.0.1.32752 > 192.168.0.1.https: tcp 0 > 14:27:00.780762 IP 192.168.0.1.https > 10.0.0.1.32752: tcp 1260 > 14:27:01.045112 IP 10.0.0.1.32752 > 192.168.0.1.https: tcp 0 > 14:27:01.045209 IP 192.168.0.1.https > 10.0.0.1.32752: tcp 1260 > 14:27:01.045263 IP 192.168.0.1.https > 10.0.0.1.32752: tcp 1260 > 14:27:01.160083 IP 10.0.0.1.32752 > 192.168.0.1.https: tcp 0 > (192.168.0.1 = bridge host, 10.0.0.1 = external host. This happened while trying to download a text file.) > > Any suggestions, or places to look for information, is appreciated. What kind of ethernet interfaces. The bridge code changes have been very small. I would suspect the TSO changes in the base stack are causing problems. Try turning TSO off on the interfaces. Another possibility is netfilter. -- Stephen Hemminger <shemminger@xxxxxxxx> OSDL http://developer.osdl.org/~shemminger
