From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <muthurajan.jayakumar@intel.com> Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by dpdk.org (Postfix) with ESMTP id 9D85C68DD for <dev@dpdk.org>; Mon, 3 Mar 2014 02:47:36 +0100 (CET) Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga102.jf.intel.com with ESMTP; 02 Mar 2014 17:44:38 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,574,1389772800"; d="scan'208";a="492576554" Received: from orsmsx110.amr.corp.intel.com ([10.22.240.8]) by orsmga002.jf.intel.com with ESMTP; 02 Mar 2014 17:49:02 -0800 Received: from orsmsx156.amr.corp.intel.com (10.22.240.22) by ORSMSX110.amr.corp.intel.com (10.22.240.8) with Microsoft SMTP Server (TLS) id 14.3.123.3; Sun, 2 Mar 2014 17:49:02 -0800 Received: from orsmsx103.amr.corp.intel.com ([169.254.2.166]) by ORSMSX156.amr.corp.intel.com ([169.254.8.214]) with mapi id 14.03.0123.003; Sun, 2 Mar 2014 17:49:02 -0800 From: "Jayakumar, Muthurajan" <muthurajan.jayakumar@intel.com> To: Jane Shen <jshen@mavenir.com>, "dev@dpdk.org" <dev@dpdk.org> Thread-Topic: Physical core vs. hyper threaded core Thread-Index: Ac82Vrk+hXP+o9JVR2ubvxJCfNUDfAAKrqeg Date: Mon, 3 Mar 2014 01:49:01 +0000 Message-ID: <5D695A7F6F10504DBD9B9187395A21797C6E7656@ORSMSX103.amr.corp.intel.com> References: <96144595DCDF66419CB40342CCD31E2E3E441B43@mbx024-e1-nj-4.exch024.domain.local> In-Reply-To: <96144595DCDF66419CB40342CCD31E2E3E441B43@mbx024-e1-nj-4.exch024.domain.local> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: 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] Physical core vs. hyper threaded core X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK <dev.dpdk.org> List-Unsubscribe: <http://dpdk.org/ml/options/dev>, <mailto:dev-request@dpdk.org?subject=unsubscribe> List-Archive: <http://dpdk.org/ml/archives/dev/> List-Post: <mailto:dev@dpdk.org> List-Help: <mailto:dev-request@dpdk.org?subject=help> List-Subscribe: <http://dpdk.org/ml/listinfo/dev>, <mailto:dev-request@dpdk.org?subject=subscribe> X-List-Received-Date: Mon, 03 Mar 2014 01:47:37 -0000 Jane,=20 Great. You are correct. Have tried enabling hyperthreading and it works.=20 For example, if we want to have the functionality partitioning such that Rx= + Packet Processing + Tx =3D all of these three functions can be done in = 2 cores - By positioning Rx in one lcore and by positioning Packet process= ing and Tx in the sibling hyperthread lcore of the same physical core, you = get tight coupling because L1 cache and L2 cache are shared between the hyp= erthreaded cores belonging to same physical core. =20 Curious to know - in your configuration, the SIP based signaling threads -= =20 Option A) are they sharing sibling of DPDK threads? Option B) Or all DPDK threads are tightly coupled with sibling threads and = SIP based signaling threads are on separate cores? If it is Option B) more tight coupling within the DPDK threads and less in= terference from signaling threads.=20 Thanks,=20 -----Original Message----- From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Jane Shen Sent: Sunday, March 02, 2014 4:56 PM To: dev@dpdk.org Subject: [dpdk-dev] Physical core vs. hyper threaded core Hi, I understand that DPDK should use the physical core. But here is what we te= sted: - Enable HT - Assign 8 cores of the CPU (an 8-core Sandybridge CPU) to DPDK. Surprisingly enough, we noticed that the remaining 8 cores (b/c there are t= otal of 16 cores after HT) can still handle other Linux processes which are= SIP based signaling transactions. Anybody can shed some light on how this worked? Is there anybody tried simi= lar thing? What has been your experience? Thanks, -Jane