From mboxrd@z Thu Jan 1 00:00:00 1970 From: Subash Abhinov Kasiviswanathan Subject: Re: [PATCH net-next v2 05/10] net: qualcomm: rmnet: Set pacing rate Date: Thu, 04 Jan 2018 15:43:28 -0700 Message-ID: <154e3adaf0825906fa3240f3b15247eb@codeaurora.org> References: <1515015787-6713-1-git-send-email-subashab@codeaurora.org> <1515015787-6713-6-git-send-email-subashab@codeaurora.org> <1515016918.131759.2.camel@gmail.com> <8bd76556945c563980a72009f9c86a13@codeaurora.org> <1515051890.131759.6.camel@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Cc: davem@davemloft.net, netdev@vger.kernel.org, lkp@intel.com To: Eric Dumazet Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:35750 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752552AbeADWn3 (ORCPT ); Thu, 4 Jan 2018 17:43:29 -0500 In-Reply-To: <1515051890.131759.6.camel@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: >> The real device over which the rmnet devices are installed also >> aggregate multiple IP packets and sends them as a single large >> aggregate >> frame to the hardware. > > It would be nice to give some details about this in the changelog. > > Also what results you get with different values for the shift (10, 9, > 8) > > My fear is that people might be tempted to blindly use the > sk_pacing_shift_update() just because a single TCP flow gets 'better' > results. > > bufferbloat is a serious issue, we do not want to allow a single TCP > flow to fill a fifo. > > Otherwise, we could remove TCP Small queues overhead from the kernel > and be happy. > > Thanks. The test was run with iperf single stream TCP TX for a duration of 30s. Pacing shift | Observed data rate (Mbps) 10 | 9 9 | 140 8 | 146 I will update all of this in the commit text in v3. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project