From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olivier Marce Date: Wed, 2 Apr 2014 12:02:36 +0200 Subject: [ath9k-devel] Retry control & iwconfig In-Reply-To: <53394313.40306@ftw.at> References: <5333A700.8070108@gmail.com> <533711D9.4020407@gmail.com> <53394313.40306@ftw.at> Message-ID: <533BE03C.3050005@alcatel-lucent.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ath9k-devel@lists.ath9k.org Hi, thanks Pradeep and Paul. I investigated on this. But as this time, I'm unable to make a link working with no_ack, even if I fix the rate. The environment is crowded, but not so much. With ACK (iw set noack_map 0 to be sure), for a iperf 10 sec long test, I found only 43 retry packets over 19k TCP packets. As soon as I set noack (iw set noack_map 9), the iperf test does not work at all. I'm able to see only 2 packets coming from the iperf client over 15 seconds of capture. The same when fixing the rate (iwconfig rate 11M), the same with 1M rate. The capture done at the 2 ends (AP and STA) are consistent. This is the same with ping, it does not work (98% packet loss) Other observations : - the ACK are well transmitted in the 2 directions - same behaviour if RTS/CTS on or off Did someone make a link with no_ack work ? In which condition ? Regards On 31/03/2014 12:27, Paul Fuxjaeger wrote: > On 29.03.14 19:32, Pradeep Reddy wrote: >> >> I think, fixing the data rates to make it behave better. > > I think so too, maybe minstrel does something very unclever in context > of NO_ACK being set (like sticking to a very high MCS). Or this is > simply what we get when turning off (fast!) mac-layer retransmission in > a busy environment and using TCP over that very leaky pipe then. > > -paul > > -- Olivier Marc? Alcatel-Lucent Bell Labs France