From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from alexa-out.qualcomm.com ([129.46.98.28]) by bombadil.infradead.org with esmtps (Exim 4.89 #1 (Red Hat Linux)) id 1eX6fB-00015A-Mg for ath10k@lists.infradead.org; Thu, 04 Jan 2018 14:38:42 +0000 From: Kalle Valo Subject: Re: Bad TCP performance on WLE900VX Date: Thu, 4 Jan 2018 14:38:14 +0000 Message-ID: <87vagh7kq2.fsf@kamboji.qca.qualcomm.com> References: In-Reply-To: (Robert Jones's message of "Tue, 2 Jan 2018 17:47:18 -0800") Content-Language: en-US MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "ath10k" Errors-To: ath10k-bounces+kvalo=adurom.com@lists.infradead.org To: Robert Jones Cc: "ath10k@lists.infradead.org" Robert Jones writes: > Hello Everyone, > > I'm using a custom arm64 board with a Cavium CN8030 CPU and testing > wireless card performance via iperf on Ubuntu 16.02 with a mainline > 4.14 kernel. I have two identical units connected to each other via > 60dB attenuators on all three channels. Channel is set to 161 VHT80. > > With UDP I see throughput upwards of 650Mbits/s, but TCP is > ~24Mbits/s. That seemed odd so I did a little more testing. Switched > to a 4.9 kernel and still saw the poor performance, but not with a > 4.4. Before I went through the trouble of bisecting I thought to ask > if there was something I was missing. > > I did come across this Ubuntu bug thread > [https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1670041] which > appeared to follow the same behavior I was seeing. Switched my TCP > congestion algorithm to reno and saw throughput jump to >330Mbits/s. > Cubic and BBR still ~24. > > My question now, is there a standing bug that I'm not aware of or > could there be some sort of problem with my configuration that is > being worked around with the reno algorithm? There's now support in TCP stack (commit below) to workaround this issue in ath10k. I tried to come up with a patch before holidays but didn't make it, anyone willing to write one? tcp: allow drivers to tweak TSQ logic https://git.kernel.org/linus/3a9b76fd0db9f0d426533f96a68a62a58753a51e -- Kalle Valo _______________________________________________ ath10k mailing list ath10k@lists.infradead.org http://lists.infradead.org/mailman/listinfo/ath10k