From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mta01.ornl.gov (mta01.ornl.gov [128.219.177.14]) by dpdk.org (Postfix) with ESMTP id 0306B9253 for ; Tue, 26 Jan 2016 17:50:32 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ornl.gov; i=@ornl.gov; q=dns/txt; s=p20151116; t=1453827033; x=1485363033; h=subject:to:references:cc:from:message-id:date: mime-version:in-reply-to; bh=bmZdO4M1/jO4BttnuPx5wfLrnhkF3glUjegxyP1jCNU=; b=fFp/D4aTeVsrdrGssZ+j7Jy7Hgeb3zZdn2KhffgI1LPEAte30yUJLtCe GthlcxzxxyVFlnWLMjX19ETBppFAa8qToWqC6RC2diKjC+hB5NZEHF7VR Tl4ArqPPfNKYFx95nU7MAXNwh/+8K8x8DD6BSZvHjiAsFQiNy64X7vbcO eqzEHyNtXn3Zv3nyvu2JNE2Wk6nu+/xD4W0BXLdCWAyj55A2CXJnTooKJ DUj7lm8Y6V0DRw+9uHBzNHxIQ39gJ4rKyqzwCh542/eezEFyabfKtTL5D yOrbt7kvR+eorSA5JnPopZmOZzCaPg1thD/DWXjPqF8N8lDCn5enjhZ6b w==; X-SG: RELAYLIST X-IronPort-AV: E=Sophos;i="5.22,350,1449550800"; d="scan'208,217";a="120510892" Received: from emgwy1.ornl.gov ([160.91.254.9]) by iron1.ornl.gov with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 26 Jan 2016 11:50:16 -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 3pqYvr4zXHz7tJr; Tue, 26 Jan 2016 11:50:16 -0500 (EST) To: Saurabh Mishra References: <56A6A46C.1050003@chocot.jp> <745DB4B8861F8E4B9849C970520ABBF149852DC7@ORSMSX102.amr.corp.intel.com> <56A78163.5060500@ornl.gov> From: Lawrence MacIntyre Message-ID: <56A7A3C8.7040200@ornl.gov> Date: Tue, 26 Jan 2016 11:50:16 -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: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Content-Filtered-By: Mailman/MimeDel 2.1.15 Cc: dev@dpdk.org 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 16:50:33 -0000 Saurabh: It sounds like you benchmarked Apache using Jumbo Packets, but not the DPDK app using large mbufs. Those are two entirely different issues. You should be able to write your packet inspection routines to work with the mbuf chains, rather than copying them into a larger buffer (although if there are multiple passes through the data, it could be a bit complicated). Copying the data into a larger buffer will definitely cause the application to be slower. Lawrence This one time (01/26/2016 09:40 AM), at band camp, Saurabh Mishra wrote: > > Hi, > > Since we do full content inspection, we will end up coalescing mbuf > chains into one before inspecting the packet which would require > allocating another buffer of larger size. > > I am inclined towards larger size mbuf for this reason. > > I have benchmarked a bit using apache benchmark and we see 3x > performance improvement over 1500 mtu. Memory is not an issue. > > My only concern is that would all the dpdk drivers work with larger > size mbuf? > > Thanks, > Saurabh > > On Jan 26, 2016 6:23 AM, "Lawrence MacIntyre" > wrote: > > 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 > -- Lawrence MacIntyre macintyrelp@ornl.gov Oak Ridge National Laboratory 865.574.7401 Cyber Space and Information Intelligence Research Group