From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by dpdk.org (Postfix) with ESMTP id 0078AFFA for ; Tue, 7 Feb 2017 17:32:59 +0100 (CET) Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga101.jf.intel.com with ESMTP; 07 Feb 2017 08:32:58 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.33,346,1477983600"; d="scan'208";a="1104234838" Received: from irsmsx102.ger.corp.intel.com ([163.33.3.155]) by fmsmga001.fm.intel.com with ESMTP; 07 Feb 2017 08:32:57 -0800 Received: from irsmsx111.ger.corp.intel.com (10.108.20.4) by IRSMSX102.ger.corp.intel.com (163.33.3.155) with Microsoft SMTP Server (TLS) id 14.3.248.2; Tue, 7 Feb 2017 16:32:56 +0000 Received: from irsmsx101.ger.corp.intel.com ([169.254.1.112]) by irsmsx111.ger.corp.intel.com ([169.254.2.109]) with mapi id 14.03.0248.002; Tue, 7 Feb 2017 16:32:56 +0000 From: "Trahe, Fiona" To: "dev@dpdk.org" CC: "De Lara Guarch, Pablo" , "Mrozowicz, SlawomirX" , "Jain, Deepak K" , "Trahe, Fiona" , "Griffin, John" , "Doherty, Declan" Thread-Topic: [PATCH] doc: add limitations section to cryptoperf guide Thread-Index: AdKBX84FoGDRP6tsRlG8mt7btOkE1g== Date: Tue, 7 Feb 2017 16:32:55 +0000 Message-ID: <348A99DA5F5B7549AA880327E580B43589182FE2@IRSMSX101.ger.corp.intel.com> Accept-Language: en-IE, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiYzI4ZDhkYWYtNjQyZi00OWFkLTgzMTYtZGJmZjQwMzQyNzdmIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX0lDIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE1LjkuNi42IiwiVHJ1c3RlZExhYmVsSGFzaCI6IjF3eWRuZWMxR0Qxc0FiQVNkWUNjNm9naSt0QXJUZHlaY0dzY1JhbzUzZzQ9In0= x-ctpclassification: CTP_IC x-originating-ip: [163.33.239.182] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: [dpdk-dev] [PATCH] doc: add limitations section to cryptoperf guide 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: Tue, 07 Feb 2017 16:33:00 -0000 Add limitations to use of the dpdk-test-crypto-perf=20 tool for hardware accelerator measurements Signed-off-by: Fiona Trahe --- doc/guides/tools/cryptoperf.rst | 16 ++++++++++++++++ 1 files changed, 16 insertions(+), 0 deletions(-) diff --git a/doc/guides/tools/cryptoperf.rst b/doc/guides/tools/cryptoperf.= rst index 6832312..af58e78 100644 --- a/doc/guides/tools/cryptoperf.rst +++ b/doc/guides/tools/cryptoperf.rst @@ -41,6 +41,22 @@ chain mode have to be specified in the command line as a= pplication parameters. These parameters are checked using device capabilities structure. =20 +Limitations: +------------ +On hardware devices the cycle-count doesn't always represent the actual of= fload +cost. The cycle-count only represents the offload cost when the hardware +accelerator is not fully loaded, when loaded the cpu cycles freed up by th= e +offload are still consumed by the test tool and included in the cycle-coun= t. +These cycles are consumed by retries and inefficient API calls enqueuing a= nd +dequeuing smaller bursts than specified by the cmdline parameter. This res= ults +in a larger cycle-count measurement and should not be interpreted as an of= fload +cost measurement. + +On hardware devices the throughput measurement is not necessarily the maxi= mum +possible for the device, e.g. it may be necessary to use multiple cores to= keep +the hardware accelerator fully loaded and so measure maximum throughput. + + Compiling the Application ------------------------- =20 --=20 1.7.0.7