Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755116AbdCWKvb (ORCPT ); Thu, 23 Mar 2017 06:51:31 -0400 Received: from mx08-00178001.pphosted.com ([91.207.212.93]:63766 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752056AbdCWKva (ORCPT ); Thu, 23 Mar 2017 06:51:30 -0400 Subject: Re: stmmac: Performance regression after commit aff3d9eff843 "net: stmmac: enable multiple buffers" To: Joao Pinto , Corentin Labbe References: <20170323100828.GC16625@Red> <68200e05-04fd-1cc1-f6d6-f77e9e6f1d9d@synopsys.com> <20170323102037.GD16625@Red> <465dc72e-8a1f-b41f-105f-add2164df6d5@st.com> CC: , , , From: Giuseppe CAVALLARO Message-ID: <5c305629-0b61-88e5-5c48-4616cd687d9f@st.com> Date: Thu, 23 Mar 2017 11:51:00 +0100 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.1.0 MIME-Version: 1.0 In-Reply-To: <465dc72e-8a1f-b41f-105f-add2164df6d5@st.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.75.127.46] X-ClientProxiedBy: SFHDAG2NODE2.st.com (10.75.127.5) To SFHDAG4NODE1.st.com (10.75.127.10) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-03-23_09:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1233 Lines: 40 On 3/23/2017 11:48 AM, Giuseppe CAVALLARO wrote: > Hello > > On 3/23/2017 11:20 AM, Corentin Labbe wrote: >>> I have a 4.21 QoS Core with 4 RX + 4 TX and detected no regression. >>> >Could you please share the iperf cmds you are using in order for me >>> to reproduce >>> >in my side? > > Joao, you have a really powerful HW integration with multiple channels > for both RX and TX. > Often this is not the same for other setup where, usually just a DMA0 > is present or, sometime, there > is just one RX extra channel. > > My question is, what happens on this kind of configurations? Are we > still guarantying the best performances? > > Also we have to guarantee, that the TSO and SG are always working. > Another point is the buffer sizes that > can be different among platforms. > > The problem below reported by Corentin push me to think that there is > a bug, so we should > understand when this has been introduced and if likely fixed by some > configuration we are > not take care right now. > > ndesc_get_rx_status: Oversized frame spanned multiple buffers" I wonder if this could be easily triggered by getting a big file via FTP. So not properly related on performance benchs peppe > > > Best Regards > Peppe >