Hi Eric, On Thu, Mar 19, 2009 at 9:50 AM, Eric W. Biederman <ebiederm@xxxxxxxxxxxx> wrote: [snip] > Bridging last I looked uses the least common denominator of hardware > offloads. Which likely explains why adding a veth decreased your > bridging performance. > At least now LRO cannot coexist bridging. So I disable the LRO feature of the myri10ge driver. >>>> Here is my experimental setting: >>>> OS: Ubuntu server 8.10 amd64 >>>> Kernel: 2.6.27-rc8 (checkout from the lxc git repository) >>> >>> I would recommend to use the 2.6.29-rc8 vanilla because this kernel does no >>> longer need patches, a lot of fixes were done in the network namespace and >>> maybe the bridge has been improved in the meantime :) >>> >> I checked out the 2.6.29-rc8 vanilla kernel. >> The performance after issuing lxc-start improved to 8.7 Gbps! >> It's a big improvement, while some performance loss remains. >> Can not we avoid this loss? > > Good question. Any chance you can profile this and see where the > performance loss seems to be coming from? > I found out this issue is caused by decreasing the MTU size. Myri-10G's MTU size is 9000 bytes; the veth' MTU size is 1500 bytes. After bridging veth, MTU size decreases from 9000 to 1500 bytes. I changed the veth's MTU size to 9000 bytes, and then I confirmed the throughput improved to 9.6 Gbps. The throughput between LXC containers also improved to 4.9 Gbps by changing the MTU sizes. So I propose to add lxc.network.mtu into the LXC configuration. How does that sound? > Eric > Best regards, Ryousei Takano _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers
