Dear Benoit, there's a lot of local matching and translation between layer2 and layer3 in your case. I wounder if it is related to the apr cache size and garbage parameters. I found [http://linux.die.net/man/7/arp]:
gc_interval (since Linux 2.2) How frequently the garbage collector for neighbor entries should attempt to run. Defaults to 30 seconds. gc_stale_time (since Linux 2.2) Determines how often to check for stale neighbor entries. When a neighbor entry is considered stale, it is resolved again before sending data to it. Defaults to 60 seconds. gc_thresh1 (since Linux 2.2) The minimum number of entries to keep in the ARP cache. The garbage collector will not run if there are fewer than this number of entries in the cache. Defaults to 128. gc_thresh2 (since Linux 2.2) The soft maximum number of entries to keep in the ARP cache. The garbage collector will allow the number of entries to exceed this for 5 seconds before collection will be performed. Defaults to 512. gc_thresh3 (since Linux 2.2) The hard maximum number of entries to keep in the ARP cache. The garbage collector will always run if there are more than this number of entries in the cache. Defaults to 1024. This still seems to be the default on recent kernels, on a box with 3.3.5 I found root@bladerunner9 ~ # cat /proc/sys/net/ipv4/neigh/default/gc* 30 60 128 512 1024 If the ARP cache get's exhausted, there must be continous additional ARP resolution traffic and latency. May you check this theory? Greetings Guido On 2013-04-23 23:34, Benoit Lourdelet wrote: > Hello, > > Forwarding throughput is decreasing gradually as I add containers. I don't > see any sudden drop. > > I we consider aggregated forwarding performance with 100 containers to be > 1, here are the measurements for > > # containers Aggregated throughput > ------------------------------------ > 100 1 > 500 .71 > 1000 .27 > 1100 .23 ------------------------------------------------------------------------------ Try New Relic Now & We'll Send You this Cool Shirt New Relic is the only SaaS-based application performance monitoring service that delivers powerful full stack analytics. Optimize and monitor your browser, app, & servers with just a few lines of code. Try New Relic and get this awesome Nerd Life shirt! http://p.sf.net/sfu/newrelic_d2d_apr _______________________________________________ Lxc-users mailing list Lxc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/lxc-users