From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by dpdk.org (Postfix) with ESMTP id 8FF292BA1 for ; Sat, 25 Feb 2017 01:21:24 +0100 (CET) Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 24 Feb 2017 16:21:22 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.35,202,1484035200"; d="scan'208";a="1102058010" Received: from orsmsx101.amr.corp.intel.com ([10.22.225.128]) by orsmga001.jf.intel.com with ESMTP; 24 Feb 2017 16:21:22 -0800 Received: from orsmsx109.amr.corp.intel.com ([169.254.11.220]) by ORSMSX101.amr.corp.intel.com ([169.254.8.118]) with mapi id 14.03.0248.002; Fri, 24 Feb 2017 16:21:22 -0800 From: "Su, David W" To: "Yigit, Ferruh" , "dev@dpdk.org" Thread-Topic: [dpdk-dev] [PATCH] igb_uio: use non-threaded ISR Thread-Index: AQHSc3IiRNCFFY74006DHm7lLodGIKF5LVOA//+UbBA= Date: Sat, 25 Feb 2017 00:21:22 +0000 Message-ID: <3875C02542CA2945BF761013C1F5B8E57F3E7953@ORSMSX109.amr.corp.intel.com> References: <1484953699-3156-1-git-send-email-david.w.su@intel.com> <22f235a0-d991-d4b0-b72d-1a2a3d5bfa82@intel.com> In-Reply-To: <22f235a0-d991-d4b0-b72d-1a2a3d5bfa82@intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiNzBkMjEwZmMtZTIwMy00MDVmLTgyYzQtMGY3M2Q5MzA3ZjdjIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX0lDIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE1LjkuNi42IiwiVHJ1c3RlZExhYmVsSGFzaCI6ImtYXC9kYW5nam01K240ZlF5UEc4a2Y1SUVvMjJNbXppRkxxNVh0WEtFbFprPSJ9 x-ctpclassification: CTP_IC x-originating-ip: [10.22.254.138] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH] igb_uio: use non-threaded ISR 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: Sat, 25 Feb 2017 00:21:25 -0000 >-----Original Message----- >From: Yigit, Ferruh >Sent: Friday, February 24, 2017 9:55 AM >To: Su, David W ; dev@dpdk.org >Subject: Re: [dpdk-dev] [PATCH] igb_uio: use non-threaded ISR > >On 1/20/2017 11:08 PM, David Su wrote: >> This eliminates the overhead of a task switch when an interrupt arrives. > >Hi David, > >Did you test patch with l3fwd-power (or any app that uses Rx >interrupts), is there any performance gain? > Hi Ferruh, The test is a simple l2 forward app and it uses the same idle heuristic as = l3fwd-power, i.e. it enables rx interrupts and goes to sleep after about 30= 0us without receiving a packet. A packet generator is configured to send a= time stamped packet every 400us to ensure the test will go through the sle= ep-wakeup cycle with every inbound packet. The packet generator measures p= acket round trip latency with the timestamps. The average latency is more than 100us on a 2.30GHz Xeon E5-2699 v3 platfor= m with Intel X540-AT2 NIC. The long latency is mostly because the DPDK ixg= be driver enables interrupt throttling in the NIC and sets the minimum inte= r-interrupt interval to about 500us. With this patch alone, there is no si= gnificant change to the average latency, the maximum latency is reduced fro= m 418us to 392us. If interrupt throttling is not enabled (http://dpdk.org/= dev/patchwork/patch/19856/), the average latency is reduced from 17us to 14= us and the maximum latency from 30us to 21us. >> >> Signed-off-by: David Su ><...>