From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail04.ics.ntt-tx.co.jp (mail05.ics.ntt-tx.co.jp [210.232.35.69]) by dpdk.org (Postfix) with ESMTP id E3E766C9B for ; Fri, 2 Nov 2018 02:39:15 +0100 (CET) Received: from gwchk03.silk.ntt-tx.co.jp (gwchk03.silk.ntt-tx.co.jp [10.107.0.111]) by mail04.ics.ntt-tx.co.jp (unknown) with ESMTP id wA21dCQP015254; Fri, 2 Nov 2018 10:39:13 +0900 Received: (from root@localhost) by gwchk03.silk.ntt-tx.co.jp (unknown) id wA21dCVs003699; Fri, 2 Nov 2018 10:39:12 +0900 Received: from gwchk.silk.ntt-tx.co.jp [10.107.0.110] by gwchk03.silk.ntt-tx.co.jp with ESMTP id LAA03698; Fri, 2 Nov 2018 10:39:12 +0900 Received: from imss06.silk.ntt-tx.co.jp (localhost [127.0.0.1]) by ccmail04.silk.ntt-tx.co.jp (unknown) with ESMTP id wA21dCxn022900; Fri, 2 Nov 2018 10:39:12 +0900 Received: from imss06.silk.ntt-tx.co.jp (localhost [127.0.0.1]) by imss06.silk.ntt-tx.co.jp (unknown) with ESMTP id wA21dCa4028626; Fri, 2 Nov 2018 10:39:12 +0900 Received: from ccmail04 (smtp03.silk.ntt-tx.co.jp [10.107.0.135]) by imss06.silk.ntt-tx.co.jp (unknown) with SMTP id wA21dCqJ028623; Fri, 2 Nov 2018 10:39:12 +0900 Date: Fri, 02 Nov 2018 10:38:23 +0900 From: Hideyuki Yamashita In-Reply-To: References: <201810310822.w9V8MaA1017463@ccmail04.silk.ntt-tx.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.74 [ja] X-CCMail7: CC-Mail-V7.0.2-Client-Relayed Message-Id: <201811020139.wA21cx3s022715@ccmail04.silk.ntt-tx.co.jp> X-TM-AS-MML: No X-CC-Mail-RelayStamp: CC-Mail-V5.14-Server To: "Zhao1, Wei" Cc: "dev@dpdk.org" Subject: Re: [dpdk-dev] Question about jumbo frame support on ixgbe X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 02 Nov 2018 01:39:16 -0000 Hi Thanks for your answering to my question. Please see inline. > Hi, Hideyuki Yamashita > > > > -----Original Message----- > > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Hideyuki Yamashita > > Sent: Wednesday, October 31, 2018 4:22 PM > > To: dev@dpdk.org > > Subject: [dpdk-dev] Question about jumbo frame support on ixgbe > > > > Hi, > > > > I have a very basic question about jumbo frame support for ixgbe. > > > > I understand that some drivers support jumbo frame and if it receive jumbo > > packet (greater than 1500 byte), it creates mbuf chains and pass it to DPDK > > application through e.g. rte_eth_rx_burst. > > > > However it looks that ixgbe driver does not support jumbo frame. > > > > Q1. Is my understanding above correct? > > Q2. If A1 equals YES, then are there any future plan to support jumbo frame > > on ixgbe? > > Your understanding above correct, but 82599 and x550 has support jumbo frame receive by now! > In order to use this feature on ixgbe, you need do the following steps: > > 1. you must set dev_conf.rxmode. max_rx_pkt_len to a big number, eg. 9500, when doing port start, for example when start port in API rte_eth_dev_start(). > ixgbe_dev_rx_init() will chose a scatter receive function if the max_rx_pkt_len is larger than the mbuf size, you do not need to set DEV_RX_OFFLOAD_SCATTER bit in > dev_conf.rxmode.offloads, this is the work of PMD driver when it detect jumbo frame is needed to be supported. Thanks for your info. > 2. set dev_conf.txmode.offloads bit of DEV_TX_OFFLOAD_MULTI_SEGS to 1 when doing rte_eth_tx_queue_setup() or , this is very important!! > If you not do this, you may only receive JUMBO frame but not forward out. Because as you say, > the receive packets maybe has a mbuf chains(depending on the size relationship of mbuf size and the max_rx_pkt_len). > But in ixgbe PMD for setting tx function, it is confusing in ixgbe_set_tx_function(), you need to take care of it, it is based on queue offloads bit! What will happen if DEV_TX_OFFLOAD_MULTI_SEGS is set to 1. Packets are sent fragmented or re-built as a Jumbo frame and sent to network? (My guess is former(packet will be sent fragmented though)) > 3. enable it using CLI "port config mtu " if you are using testpmd or using API rte_eth_dev_set_mtu() for your own APP. > The mtu number is just what you need to update for a large number. I want to know the relationship between 1,2 and 3. Do I have to do all 3 steps to send/receive jumbo frame? Or, when I relalize jumbo frame support programatically execute 1 and 2, if I do not modify program and just change setting via CLI then execute 3? Thanks and BR, Hideyuki Yamashita NTT TechnoCross > And all my discussion is based on pf port, if you are using vf, we can have a further discussion. > Please feel free to contact me if necessary. > > > > > BR, > > Hideyuki Yamashita > > NTT TechnoCross >