From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by dpdk.org (Postfix) with ESMTP id 1EF5658D7 for ; Mon, 7 Apr 2014 15:02:59 +0200 (CEST) Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga102.jf.intel.com with ESMTP; 07 Apr 2014 05:56:34 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,810,1389772800"; d="scan'208";a="488595060" Received: from irsmsx104.ger.corp.intel.com ([163.33.3.159]) by orsmga001.jf.intel.com with ESMTP; 07 Apr 2014 05:56:16 -0700 Received: from irsmsx103.ger.corp.intel.com ([169.254.3.172]) by IRSMSX104.ger.corp.intel.com ([169.254.5.224]) with mapi id 14.03.0123.003; Mon, 7 Apr 2014 13:55:39 +0100 From: "Richardson, Bruce" To: Marc Sune , "" Thread-Topic: [dpdk-dev] RTE_EAL on single core CPUs Thread-Index: AQHPUmAIXp2GFlVhaken1E3ImGcYD5sGG6ZA Date: Mon, 7 Apr 2014 12:55:38 +0000 Message-ID: <59AF69C657FD0841A61C55336867B5B01A9F91D0@IRSMSX103.ger.corp.intel.com> References: <53429F2F.7050602@bisdn.de> In-Reply-To: <53429F2F.7050602@bisdn.de> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [163.33.239.181] Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] RTE_EAL on single core CPUs 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: Mon, 07 Apr 2014 13:03:00 -0000 > -----Original Message----- > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Marc Sune > Sent: Monday, April 07, 2014 1:51 PM > To: > Subject: [dpdk-dev] RTE_EAL on single core CPUs > > Dear all, > > I was preparing a development machine (kvm - qemu) with a single core, an= d stumbled with=20 > what appears to be a limitation with EAL [1].=20 > The VM is setup emulating a SandyBridge CPU but with a single CPU and run= ning > 1.6.0 branch HEAD (perhaps this is the problem?=BF). > > I was also interested in this particular setup, because we haven't yet tr= ied our application=20 > with some Atom equipment we have here, but we need to make it run also th= ere. > > Any ideas? I am probably missing something really fundamental here. Hi Marc, I think in your case you've hit more a limitation of the particular app, ra= ther than one for the EAL. L2fwd requires more than a single core to run, b= ut you can easily write applications that can handle packets from multiple = ports using a single core.=20 Where you may hit issues, though, is that you cannot isolate the single cor= e cpu from the linux kernel, so you may need to ensure you have enough buff= ering throughout the app to avoid packet loss when the kernel interrupts yo= u to do its own house-keeping tasks. Regards, /Bruce