From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mta02.ornl.gov (mta02.ornl.gov [128.219.177.12]) by dpdk.org (Postfix) with ESMTP id DB7818E85 for ; Tue, 26 Jan 2016 15:23:32 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ornl.gov; i=@ornl.gov; q=dns/txt; s=p20151116; t=1453818212; x=1485354212; h=subject:to:references:from:message-id:date:mime-version: in-reply-to:content-transfer-encoding; bh=+o0Ooqg82vZxg1WNB74jVksVuj2wlZoddecuiBfFf1c=; b=Hny9uS7rE/kLQjmJANTu+wr5T7hvfLMMQik6t3cQog95ANmJuInv2dIJ WCR8XyMEYnuaZcvjN9NL2vKxTpxhcf5mq0ftS6pEPkXydEHB/pLPCwI5H f0Yl8yuQqIzl66BHB6fHoIxvZDRUHwYo/XNJbZSxmvADr2/KgpBmzw8Ip S3/h0oa13tSKS+WU7ASBHA98KRkr/PIlXxuiu9bISnYwuK+aodChzx0Np HiN7pl2F1HbQEYdFgfCDSqdp4HNVxQdMModqmVvx63IIy/ugPZuf2ip7w 79wpRVfnzuxzT/H72kIhwxVyB89lYxE8Thm/5/FBt5OcDBNkOx6QSEe8p w==; X-SG: RELAYLIST X-IronPort-AV: E=Sophos;i="5.22,350,1449550800"; d="scan'208";a="96593989" Received: from emgwy1.ornl.gov ([160.91.254.9]) by iron2.ornl.gov with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 26 Jan 2016 09:23:32 -0500 Received: from [160.91.76.47] (lumos.ornl.gov [160.91.76.47]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by emgwy1.ornl.gov (Postfix) with ESMTPS id 3pqVfX1rTYz7tSf for ; Tue, 26 Jan 2016 09:23:32 -0500 (EST) To: dev@dpdk.org References: <56A6A46C.1050003@chocot.jp> <745DB4B8861F8E4B9849C970520ABBF149852DC7@ORSMSX102.amr.corp.intel.com> From: Lawrence MacIntyre Message-ID: <56A78163.5060500@ornl.gov> Date: Tue, 26 Jan 2016 09:23:31 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 MIME-Version: 1.0 In-Reply-To: <745DB4B8861F8E4B9849C970520ABBF149852DC7@ORSMSX102.amr.corp.intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-dev] rte_mbuf size for jumbo frame X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 26 Jan 2016 14:23:33 -0000 Saurabh: Raising the mbuf size will make the packet handling for large packets slightly more efficient, but it will use much more memory unless the great majority of the packets you are handling are of the jumbo size. Using more memory has its own costs. In order to evaluate this design choice, it is necessary to understand the behavior of the memory subsystem, which is VERY complicated. Before you go down this path, at least benchmark your application using the regular sized mbufs and the large ones and see what the effect is. This one time (01/26/2016 09:01 AM), at band camp, Polehn, Mike A wrote: > Jumbo frames are generally handled by link lists (but called something else) of mbufs. > Enabling jumbo frames for the device driver should enable the right portion of the driver which handles the linked lists. > > Don't make the mbufs huge. > > Mike > > -----Original Message----- > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Masaru OKI > Sent: Monday, January 25, 2016 2:41 PM > To: Saurabh Mishra; users@dpdk.org; dev@dpdk.org > Subject: Re: [dpdk-dev] rte_mbuf size for jumbo frame > > Hi, > > 1. Take care of unit size of mempool for mbuf. > 2. Call rte_eth_dev_set_mtu() for each interface. > Note that some PMDs does not supported change MTU. > > On 2016/01/26 6:02, Saurabh Mishra wrote: >> Hi, >> >> We wanted to use 10400 bytes size of each rte_mbuf to enable Jumbo frames. >> Do you guys see any problem with that? Would all the drivers like >> ixgbe, i40e, vmxnet3, virtio and bnx2x work with larger rte_mbuf size? >> >> We would want to avoid detailing with chained mbufs. >> >> /Saurabh -- Lawrence MacIntyre macintyrelp@ornl.gov Oak Ridge National Laboratory 865.574.7401 Cyber Space and Information Intelligence Research Group