> > Here is my list of points, hoping that the others will add theirs, too: > > * would be good to have a standardised set of scripts, > for > comparison/benchmarking > > * the built-in VoIP module only works for UDP -- is it possible > to > port this to DCCP? > > * as per previous email, more complex traffic scenarios would be > good, > in particular > - switching on/off background traffic at times to > observe > TCP/flow-friendliness > - running multiple DCCP flows in parallel and at overlapping times > The scenario that I mostly use is limiting the bandwidth with a middlebox running TBF. However, all of the recent trees except 2.6.20final_dccp (2.6.20 patched with Ian's modifications) that I have tested fail to achieve acceptable transfer rates. Test setup is as follows, unless otherwise mentioned: - Two Linux boxes are connected through another Linux box (middlebox) running netem. The boxes at the edge are identical machines with P4 2.4GHz and 512MB memory. Middlebox is a P4 2.6GHz with 512MB memory. - TBF is used to limit the bandwidth. TBF buffer is set as 10000 bytes and the limit is 30000 bytes. - 20ms constant delay is present in both sender->receiver and receiver->sender directions. - iperf in bytestream mode is used in these tests, and the streaming duration is set as 60 seconds. - DCCPv4 is used in the tests. Below are the results of the two different trees: Kernel: 2.6.20final_dccp (2.6.20 davem tree with Ian's patches - except for the best_packet_next patch. The patches applied are not the latest ones which are updated at 2nd of December, but the ones before the latest.) Results: Bottleneck=1000Kbps, tx_qlen=5: 0.0-60.3 sec 6.86 MBytes 955 Kbits/sec Bottleneck=2000Kbps, tx_qlen=5: 0.0-60.1 sec 13.3 MBytes 1.86 Kbits/sec Bottleneck=5000Kbps, tx_qlen=5: 0.0-60.0 sec 27.2 MBytes 3.80 Kbits/sec Bottleneck=10000Kbps, limit=50000bytes, tx_qlen=5: 0.0-60.0 sec 43.6 MBytes 6.09 Kbits/sec Kernel: 2.6.24-rc4 (Gerrit's latest tree): Results (Bottleneck bandwidth, tx_qlen: iperf server output): Bottleneck=1000Kbps, tx_qlen=5: 0.0-168.2 sec 107 KBytes 5.21 Kbits/sec Bottleneck=1000Kbps, tx_qlen=0: 0.0-147.8 sec 157 KBytes 8.71 Kbits/sec Bottleneck=2000Kbps, tx_qlen=5: 0.0-89.0 sec 138 KBytes 12.7 Kbits/sec Bottleneck=2000Kbps, tx_qlen=0: 0.0-103.9 sec 203 KBytes 16.0 Kbits/sec Bottleneck=5000Kbps, tx_qlen=5: 0.0-66.6 sec 222 KBytes 27.3 Kbits/sec Bottleneck=5000Kbps, tx_qlen=0: 0.0-100.2 sec 314 KBytes 25.7 Kbits/sec Bottleneck=10000Kbps, tx_qlen=5: 0.0-60.5 sec 1.30 MBytes 181 Kbits/sec Bottleneck=10000Kbps, tx_qlen=0: 0.0-65.3 sec 922 KBytes 116 Kbits/sec While writing this mail, I noticed that Ian has updated his patch set for 2.6.20. I will use this set and repeat the tests this week, hopefully. Moreover, I also tested Ian's patches for other trees (2.6.22 and 2.6.24) but the results were not as good as 2.6.20final_dccp results, if I remember correctly. I can go over them again, if necessary. > > Gerrit > - Burak - To unsubscribe from this list: send the line "unsubscribe dccp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
