From mboxrd@z Thu Jan 1 00:00:00 1970 From: Johannes Deleu Date: Thu, 22 Jun 2006 12:41:42 +0000 Subject: mail voor linux mailinglist Message-Id: <449A9006.9030608@intec.ugent.be> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: dccp@vger.kernel.org Hi, for a project, we're interested in using DCCP. As such, I did some performance measurements with the latest version of the DCCP implementation. To my opinion, they are not really what I expected. Could you give some ideas or maybe some information about the current status of the implementation (e.g. is packet loss detection planned for implementation, when ?) ? Results of similar tests are also interesting to see if they compare. For the tests, I used an impairment node (based on linux, which introduced some packet loss). Measurements where performed with the patched iperf on linux-2.6.16.20 and I came to the following table: TCP DCCP-CCID3 (Send/Recv) No drop 94 Mbps 93.3 Mbps 93.2 Mbps Drop 1% 83.4 Mbps 93.3 Mbps 92.3 Mbps Drop 5% 16.6 Mbps 93.3 Mbps 88.6 Mbps Drop 10% 3.25 Mbps 93.3 Mbps 83.9 Mbps The transmitter does not detect the packet loss and doesnt slow down, instead it keeps sending . As CCID3 is TFRC, I expected similar results for TCP and DCCP-CCID3. When i tried out linux-2.6.17.1 (no packet drop) the receiver seems to stop sending feedback packets after a while and the transmitter slows down. The receiving process doesnt receive any data (recv doesnt return). [ 3] local 10.0.1.3 port 3743 connected with 10.0.1.1 port 5001 [ 3] 0.0- 1.0 sec 11.0 MBytes 92.5 Mbits/sec [ 3] 1.0- 2.0 sec 10.9 MBytes 91.6 Mbits/sec [ 3] 2.0- 3.0 sec 10.9 MBytes 91.6 Mbits/sec [ 3] 3.0- 4.0 sec 10.9 MBytes 91.6 Mbits/sec [ 3] 4.0- 5.0 sec 10.9 MBytes 91.6 Mbits/sec [ 3] 5.0- 6.0 sec 10.9 MBytes 91.6 Mbits/sec [ 3] 6.0- 7.0 sec 6.86 MBytes 57.5 Mbits/sec [ 3] 7.0- 8.0 sec 194 KBytes 1.59 Mbits/sec [ 3] 8.0- 9.0 sec 100 KBytes 819 Kbits/sec [ 3] 9.0-10.0 sec 100 KBytes 819 Kbits/sec [ 3] 10.0-11.0 sec 100 KBytes 819 Kbits/sec [ 3] 11.0-12.0 sec 100 KBytes 819 Kbits/sec [ 3] 12.0-13.0 sec 100 KBytes 819 Kbits/sec best regards, Johannes