From patchwork Tue Dec 2 23:41:06 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Siobhan Butler X-Patchwork-Id: 1740 Return-Path: X-Original-To: patchwork@dpdk.org Delivered-To: patchwork@dpdk.org Received: from [92.243.14.124] (localhost [IPv6:::1]) by dpdk.org (Postfix) with ESMTP id 59B808045; Wed, 3 Dec 2014 00:41:30 +0100 (CET) Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by dpdk.org (Postfix) with ESMTP id 3F7137E75 for ; Wed, 3 Dec 2014 00:41:26 +0100 (CET) Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga103.jf.intel.com with ESMTP; 02 Dec 2014 15:38:02 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.04,691,1406617200"; d="scan'208";a="492598260" Received: from irvmail001.ir.intel.com ([163.33.26.43]) by orsmga003.jf.intel.com with ESMTP; 02 Dec 2014 15:37:57 -0800 Received: from sivswdev02.ir.intel.com (sivswdev02.ir.intel.com [10.237.217.46]) by irvmail001.ir.intel.com (8.14.3/8.13.6/MailSET/Hub) with ESMTP id sB2NfBAZ004794; Tue, 2 Dec 2014 23:41:11 GMT Received: from sivswdev02.ir.intel.com (localhost [127.0.0.1]) by sivswdev02.ir.intel.com with ESMTP id sB2NfBcV016731; Tue, 2 Dec 2014 23:41:11 GMT Received: (from sabutler@localhost) by sivswdev02.ir.intel.com with id sB2NfBZx016727; Tue, 2 Dec 2014 23:41:11 GMT From: Siobhan Butler To: dev@dpdk.org Date: Tue, 2 Dec 2014 23:41:06 +0000 Message-Id: <1417563667-16686-2-git-send-email-siobhan.a.butler@intel.com> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1417563667-16686-1-git-send-email-siobhan.a.butler@intel.com> References: <1417563667-16686-1-git-send-email-siobhan.a.butler@intel.com> Subject: [dpdk-dev] [PATCH 1/2] doc: updated i40e enabling additonal fnct in gsg 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: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Updated the i40e Enabling Additional Functionality section (5.7) of DPDK Getting Started Guide. Signed-off-by: Siobhan Butler Signed-off-by: Helin Zhang Acked-by: Bernard Iremonger --- doc/guides/linux_gsg/enable_func.rst | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/doc/guides/linux_gsg/enable_func.rst b/doc/guides/linux_gsg/enable_func.rst index ac12d51..00c6d9e 100644 --- a/doc/guides/linux_gsg/enable_func.rst +++ b/doc/guides/linux_gsg/enable_func.rst @@ -171,6 +171,10 @@ Please note that while using iommu=pt is compulsory for igb_uio driver, the vfio High Performance of Small Packets on 40G NIC -------------------------------------------- +As there might be firmware fixes for performance enhancement in latest version +of firmware image, the firmware update might be needed for getting high performance. +Check with the local Intel's Network Division application engineers for firmware updates. + Enabling Extended Tag and Setting Max Read Request Size ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ @@ -198,3 +202,13 @@ Use 16 Bytes RX Descriptor Size As i40e PMD supports both 16 and 32 bytes RX descriptor sizes, and 16 bytes size can provide helps to high performance of small packets. Configuration of CONFIG_RTE_LIBRTE_I40E_16BYTE_RX_DESC in config files can be changed to use 16 bytes size RX descriptors. + +High Performance and per Packet Latency Tradeoff +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Due to the hardware design, the interrupt signal inside NIC is needed for per +packet descriptor write-back. The minimum interval of interrupts could be set +at compile time by CONFIG_RTE_LIBRTE_I40E_ITR_INTERVAL in configuration files. +Though there is a default configuration, the interval could be tuned by the +users with that configuration item depends on what the user cares about more, +performance or per packet latency.