From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from [208.74.158.174] (helo=mail3.candelatech.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hRMhB-0002xj-Mm for ath10k@lists.infradead.org; Thu, 16 May 2019 20:09:43 +0000 Subject: Re: Problem with 9984 in routed mode with 512b frames. References: <10ed4e39-4364-c8ef-2b38-15ea7672ad94@candelatech.com> <2ec6f626-6391-f9b5-918c-99ad7e6b3e31@newmedia-net.de> <55b50a9a-49f4-d669-22d4-84e2efabf451@candelatech.com> From: Ben Greear Message-ID: Date: Thu, 16 May 2019 13:09:40 -0700 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "ath10k" Errors-To: ath10k-bounces+kvalo=adurom.com@lists.infradead.org To: Adrian Chadd Cc: Sebastian Gottschall , ath10k On 5/16/19 12:55 PM, Adrian Chadd wrote: > You can totally go down to OFDM yeah but you then need to send it at > 20MHz and non-AMPDU. > > Is it maybe the retry code + rate control code is retagging an AMPDU > at a lower rate and it's transitioning down to CCK/OFDM without > breaking the AMPDU apart? It was sending a one-frame AMPDU, and one frame AMSDU for that matter. Maybe there is some bit in the tx descriptor that needed to be twiddled as well to make OFDM able to work, but I don't know what that would be. Is there any advantage of (any) OFDM over MCS0 HT 20Mhz as far as range or SNR goes? The chart I found made it look like there was not, and if not, then why bother at all with OFDM if peer advertises HT/VHT rates? Thanks, Ben > > > -a > > On Thu, 16 May 2019 at 12:40, Ben Greear wrote: >> >> On 5/15/19 6:00 AM, Ben Greear wrote: >>> On 5/15/19 5:26 AM, Sebastian Gottschall wrote: >>>> >>>> Am 15.05.2019 um 14:20 schrieb Ben Greear: >>>>> On 05/14/2019 09:26 PM, Sebastian Gottschall wrote: >>>>>> can you send me a detailed instruction for testing this on my devices? so which commands have been used for generating the traffic etc. (iperf3?) >>>>> >>>>> I am using our own traffic generator, but I imagine iperf3 should work fine too. >>>>> >>>>> I am testing on x86-64 and so forth. Maybe you can test with UDP small-packet load on your platform >>>>> in routed mode (ie, external iperf generator through your AP) and see if you see issues? >>>> thats the plan. can you do a test with iperf3 to see if its reproduceable. i mean i will test it on ipq based boards and x64. but to make sure that the scenario >>>> is identical which raised up your issue, it would be find if we have identical software for testing including the same options >> >> I think I found the issue. The rate-ctrl logic in the firmware allows a transition from HT/VHT 20 MCS0 down to OFDM rates. >> It seems the hardware does not like to see an AMPDU with an OFDM rate for 20Mhz and a VHT rate for 80Mhz (or maybe just the >> single OFDM rate is the fault). >> >> If you can edit firmware, then setting this to 0 probably fixes the issue. >> >> g_rc_cck_rate_allowed >> >> I think to reproduce you'd need to send high speed traffic in a situation where the >> RF environment is going to make rate-ctrl fail quite a bit. (Slow speed should >> work too, but it would likely take a lot longer). >> >> And, it is always possible that whatever I saw when testing mostly-stock FW is different >> from what I eventually debugged to in my firmware. Still, from looking at MCS vs SNR >> charts, there seems to be no advantage to trying OFDM vs MCS0 for 20Mhz. >> >> Thanks, >> Ben >> >> -- >> Ben Greear >> Candela Technologies Inc http://www.candelatech.com >> >> >> _______________________________________________ >> ath10k mailing list >> ath10k@lists.infradead.org >> http://lists.infradead.org/mailman/listinfo/ath10k > -- Ben Greear Candela Technologies Inc http://www.candelatech.com _______________________________________________ ath10k mailing list ath10k@lists.infradead.org http://lists.infradead.org/mailman/listinfo/ath10k