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 484E44CC0 for ; Thu, 1 Mar 2018 23:40:42 +0100 (CET) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 01 Mar 2018 14:40:40 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.47,409,1515484800"; d="scan'208";a="204848319" Received: from fmsmsx104.amr.corp.intel.com ([10.18.124.202]) by orsmga005.jf.intel.com with ESMTP; 01 Mar 2018 14:40:40 -0800 Received: from hasmsx111.ger.corp.intel.com (10.184.198.39) by fmsmsx104.amr.corp.intel.com (10.18.124.202) with Microsoft SMTP Server (TLS) id 14.3.319.2; Thu, 1 Mar 2018 14:40:40 -0800 Received: from hasmsx105.ger.corp.intel.com ([169.254.1.222]) by HASMSX111.ger.corp.intel.com ([169.254.5.112]) with mapi id 14.03.0319.002; Fri, 2 Mar 2018 00:40:37 +0200 From: "Stojaczyk, DariuszX" To: "dev@dpdk.org" , "Tan, Jianfeng" , Maxime Coquelin , "Burakov, Anatoly" , Yuanhan Liu CC: "Harris, James R" , Thomas Monjalon Thread-Topic: virtio with 2MB hugepages - bringing back single file segments Thread-Index: AdOxqqyA5D5OnZTzTTaCvVf8X7xKdg== Date: Thu, 1 Mar 2018 22:40:36 +0000 Message-ID: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: dlp-product: dlpe-windows dlp-version: 11.0.0.116 dlp-reaction: no-action x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiZDRjZWVmYjMtYjYxMS00NGQ0LTg1NzEtNGEwMmQ2MTNlOWU3IiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX0lDIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE2LjUuOS4zIiwiVHJ1c3RlZExhYmVsSGFzaCI6IlhidGhhS0RZUXFGbjRQbkZ5VEhiS1wvZUp2NDZLdVlFQ2Q0bXdmZ2NOTVQwPSJ9 x-ctpclassification: CTP_IC x-originating-ip: [10.104.73.218] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: [dpdk-dev] virtio with 2MB hugepages - bringing back single file segments 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: Thu, 01 Mar 2018 22:40:43 -0000 Hi, I'm trying to make a vhost-user initiator built upon DPDK work with 2MB hug= epages. In the initiator we have to share all memory with the host process,= so it can perform DMA. DPDK currently enforces having one descriptor per hugepage= and there's an artificial limit of shared descriptors in DPDK vhost-user i= mplementation (currently 8). Because of that, all DPDK vhost-user initiator= s are practically limited to 1GB hugepages at the moment. We can always inc= rease the artificial descriptor limit, but then we're limited by sendmsg() = itself, which on Linux accepts no more than 253 descriptors. However, could= we increase the vhost-user implementation limit to - say - 128, and bring = back "single file segments" [1]? Could I send a patch series that does this? The single file segments code w= ould go through a cleanup - at least making it available via a runtime opti= on rather than #ifdefs. I know there's an ongoing rework of the memory allocator in DPDK [2] and it= includes a similar single file segments functionality. However, it will pr= obably take quite some time before merged and even then, the new functional= ity would only be available in the *new* allocator. The old one is kept unc= hanged. It could use single file segments as well. Regards, D. [1] http://dpdk.org/dev/patchwork/patch/16042/ [2] http://dpdk.org/ml/archives/dev/2017-December/084302.html=20