On Mon, Jun 11, 2012 at 06:14:17PM +0500, Junaid Khalid wrote: > With the following are the platform specifications: > > OVS version: 1.4.0 > traffic type: MTU size UDP packets @7000packets per second, generating > 50,000 flows by changing UDP src Ports. > OS: Fedora release 12, Linux 2.6.31.5-127.fc12.i686.PAE > CPU: Intel Core i3 @ 2100 GHz > Controller: NOX, simple IP based switching application. > > > If I generate 50,000 flows in two chunks, for example, first I generate > traffic with src Port from 1 to 20,000 for few seconds then change the src > Port range to 20,001 to 50,000, I get the following warnings: > > Jun 11 16:41:06|00019|dpif|WARN|system@br0: recv failed (No buffer space > available) > Jun 11 16:41:19|00020|dpif|WARN|system@br0: recv failed (No buffer space > available) > Jun 11 16:41:22|00021|dpif|WARN|system@br0: recv failed (No buffer space > available) > Jun 11 16:41:24|00022|dpif|WARN|system@br0: recv failed (No buffer space > available) > > Following is the output of "ovs-dpctl show br0" > > system@br0: > lookups: hit:491818 missed:603323 lost:116749 > flows: 28559 > > Moreover, if I generate 50,000 flows in one go, without any pause, then I > do not get any error. > > How to diagnose the problem? Has anyone else experienced such problem with > reactive flow writing?
The problem is that packets are being dropped in the kernel-to-user buffers. You can try Open vSwitch from the "master" or "branch-1.7" branches, which should handle this workload much better. If your controller is receiving the first packet of every UDP flow, I'm surprised that it can keep up. _______________________________________________ discuss mailing list [email protected] http://openvswitch.org/mailman/listinfo/discuss
