> Does the ng_hub cause the packet to be copied? If so you've > still got the same number of copies as vanilla BPF.
ng_hub does copy a packets. But, this does not explain the test results. the benchmark works like this: 1. connect ng_mmq node to ng_hub 2. run benchmark for mmq 3. open pcap device (mmq node still connected) 4. run benchmark for pcap (mmq node still connected) so, ng_mmq and ng_hub are working during pcap benchmark, so additional copies do not explain it. the strange thing is: why bpf, which does context switches, works more efficiently than grabbing packets directly from memory mapped chunk ? did I overlook something significant ? I was thinking that while application spins awaiting data, scheduler may detach it from the CPU, and then ringbuffer may be overflown. I increased the priority to ridiculous values, and increased ringbuffer size to as large as 32 Megabytes. The best I got is the same results as pcap. Can anybody explain this ? Example test, moderate traffic generated by the ping -f: # ./benchmark rl0 /dev/mmq16 10000 desc rcvd dropped seen totlen pps time (sec) mmq 10784 770 10000 13420000 10076 1.070 pcap 10016 0 10000 13420000 9093 1.102 _______________________________________________ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[EMAIL PROTECTED]"
