From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Donecker Date: Wed, 13 Jun 2012 19:37:12 -0700 Subject: [ath9k-devel] Very large datagram loss Message-ID: <4FD94E58.4070503@ahmct.ucdavis.edu> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ath9k-devel@lists.ath9k.org Hi, I am experiencing very high datagram loss between two identical cards communicating over a single spacial stream in adhoc mode. Using minstrel_ht rate control the tx bitrate settles at MCS7 150Mbps, and I get the following iperf results. # iperf -c 192.168.11.2 -p 7777 -u -b 150m -t 10 -i 1 ------------------------------------------------------------ Client connecting to 192.168.11.2, UDP port 7777 Sending 1470 byte datagrams UDP buffer size: 160 KByte (default) ------------------------------------------------------------ [ 3] local 192.168.11.1 port 43287 connected with 192.168.11.2 port 7777 [ ID] Interval Transfer Bandwidth [ 3] 0.0- 1.0 sec 16.1 MBytes 135 Mbits/sec [ 3] 1.0- 2.0 sec 16.3 MBytes 137 Mbits/sec [ 3] 2.0- 3.0 sec 16.3 MBytes 137 Mbits/sec [ 3] 3.0- 4.0 sec 15.9 MBytes 133 Mbits/sec [ 3] 4.0- 5.0 sec 16.4 MBytes 138 Mbits/sec [ 3] 5.0- 6.0 sec 16.0 MBytes 134 Mbits/sec [ 3] 6.0- 7.0 sec 16.2 MBytes 136 Mbits/sec [ 3] 7.0- 8.0 sec 16.0 MBytes 135 Mbits/sec [ 3] 8.0- 9.0 sec 16.2 MBytes 136 Mbits/sec [ 3] 0.0-10.0 sec 161 MBytes 135 Mbits/sec [ 3] Sent 115053 datagrams [ 3] Server Report: [ 3] 0.0-10.0 sec 92.0 MBytes 77.0 Mbits/sec 0.262 ms 49459/115052 (43%) [ 3] 0.0-10.0 sec 1 datagrams received out-of-order When I set minstrel_ht to fixed_rate MCS7 I get the following iperf results. # iperf -c 192.168.11.2 -p 7777 -u -b 150m -t 10 -i 1 ------------------------------------------------------------ Client connecting to 192.168.11.2, UDP port 7777 Sending 1470 byte datagrams UDP buffer size: 160 KByte (default) ------------------------------------------------------------ [ 3] local 192.168.11.1 port 55776 connected with 192.168.11.2 port 7777 [ ID] Interval Transfer Bandwidth [ 3] 0.0- 1.0 sec 17.4 MBytes 146 Mbits/sec [ 3] 1.0- 2.0 sec 17.4 MBytes 146 Mbits/sec [ 3] 2.0- 3.0 sec 17.6 MBytes 147 Mbits/sec [ 3] 3.0- 4.0 sec 17.4 MBytes 146 Mbits/sec [ 3] 4.0- 5.0 sec 17.5 MBytes 147 Mbits/sec [ 3] 5.0- 6.0 sec 17.6 MBytes 148 Mbits/sec [ 3] 6.0- 7.0 sec 17.4 MBytes 146 Mbits/sec [ 3] 7.0- 8.0 sec 17.4 MBytes 146 Mbits/sec [ 3] 8.0- 9.0 sec 17.8 MBytes 149 Mbits/sec [ 3] 0.0-10.0 sec 175 MBytes 147 Mbits/sec [ 3] Sent 124930 datagrams [ 3] Server Report: [ 3] 0.0-10.2 sec 10.2 MBytes 8.39 Mbits/sec 4.527 ms 117609/124920 (94%) [ 3] 0.0-10.2 sec 1 datagrams received out-of-order In either case the overall throughput and datagram loss percentages are terrible. I believe overall the datagram loss should be less than a few percent. Any ideas how I can determine where the packets are getting lost? Thanks, -Stephen -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.ath9k.org/pipermail/ath9k-devel/attachments/20120613/c1b0d529/attachment-0001.htm