From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ua0-f196.google.com (mail-ua0-f196.google.com [209.85.217.196]) by dpdk.org (Postfix) with ESMTP id B8D53292D; Wed, 21 Jun 2017 08:15:31 +0200 (CEST) Received: by mail-ua0-f196.google.com with SMTP id z34so14194380uab.0; Tue, 20 Jun 2017 23:15:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=1E/QL4blHmiMMA8cHSwHEnoTVqhIY0sh7qBGlRJn5zw=; b=FUEJYY1senw40qaFzwwyEYYKBL+1/+/WbvYPxsMxIr2bI9AX7yfxrQY99cJF7I4b5k U1DEW6haSS1nnnSvpfjx6tvhyuXf8vxhyuthJtDf09+T8jPdGCvvIEx8NDkAdnaLPU1x tUYaIFWHKtU4o3jdsXcHxZEBoBsY4YJ/QfwlkYNyqvQY+Q/eeI8qAWWzNYyJ9bvrRLBS 6xr/lSr7jnMXfocuR83K7i77rsnNDaGS1XihwKcF5VbA4SP2oR0ZuWM+hpzAwUUmWLXo FK6SIYsYFpaZrtky000T9R5I0vLRuF9V1dpOK+AOiw8Hc5RzIgBnnDSLe4ImhgE3rXmt NasQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=1E/QL4blHmiMMA8cHSwHEnoTVqhIY0sh7qBGlRJn5zw=; b=CkIjCAsLJGYiYrNr0kx2L+jlgVifXMNAERrvMI1BsmVw6RkiccTOg4781j+OJnAu2+ eBP+oNm7DQnwqkA8Pqu0OeqY6du4Ppqvp4cc+GbyWsSC40Ko6cB6n6V+8405nByLbTx6 Y5j0BAFmiK+4ZI1Jc6yjDqJDNbDZ1vKzHEIXMpnWaNCrhl6W4vZW3bc2InyHTM1aA/Zx gwBfRM21RPxgdebK1Mbh/JHxB6g9uoJSWqIXxgcRbsKN/SxdmKPRDRFVHNtbOoK9rrgq qTD3aUhUZqVwTtbYQbptlvM3kdltLq4Dth4FdEkL8F2I+rfL0IawgtBwrLxZeGF+L0J2 cb1w== X-Gm-Message-State: AKS2vOxD5Yx6GxPWhkRlORbgNLkrP7oDaZmZtpz29kw/PtiF87N9yfTu fhvfXNbjqzIcqvlZKIfSLzIdJbe5dA== X-Received: by 10.159.49.84 with SMTP id n20mr11019748uab.117.1498025730016; Tue, 20 Jun 2017 23:15:30 -0700 (PDT) MIME-Version: 1.0 Received: by 10.103.19.135 with HTTP; Tue, 20 Jun 2017 23:15:29 -0700 (PDT) In-Reply-To: References: From: Pavel Shirshov Date: Tue, 20 Jun 2017 23:15:29 -0700 Message-ID: To: Sam Cc: dev@dpdk.org, users@dpdk.org, qemu-devel@nongnu.org, qemu-discuss@nongnu.org Content-Type: text/plain; charset="UTF-8" Subject: Re: [dpdk-dev] Will huge page have negative effect on guest vm in qemu enviroment? 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: Wed, 21 Jun 2017 06:15:32 -0000 Hi Sam, Below I'm saying about KVM. I don't have experience with vbox and others. 1. I'd suggest don't use dpdk inside of VM if you want to see best perfomance on the box. 2. huge pages enabled globally will not have any bad effect to guest OS. Except you have to enable huge pages inside of VM and provide real huge page for VM's huge pages from the host system. Otherwise dpdk will use "hugepages" inside of VM, but this "huge pages" will not real ones. They will be constructed from normal pages outside. Also when you enable huge pages OS will reserve them from start and your OS will not able use them for other things. Also you can't swap out huge pages, KSM will not work for them and so on. 3. You can enable huge pages just for one numa node. It's impossible to enable them just for one core. Usually you reserve some memory for hugepages when the system starts and you can't use this memory in normal applications unless normal application knows how to use them. Also why it didn't work inside of the docker? On Tue, Jun 20, 2017 at 8:35 PM, Sam wrote: > BTW, we also think about use ovs-dpdk in docker enviroment, but test result > said it's not good idea, we don't know why. > > 2017-06-21 11:32 GMT+08:00 Sam : > >> Hi all, >> >> We plan to use DPDK on HP host machine with several core and big memory. >> We plan to use qemu-kvm enviroment. The host will carry 4 or more guest vm >> and 1 ovs. >> >> Ovs-dpdk is much faster then normal ovs, but to use ovs-dpdk, we have to >> enable huge page globally. >> >> My question is, will huge page enabled globally have negative effect on >> guest vm's memory orperate or something? If it is, how to prevent this, or >> could I enable huge page on some core or enable huge page for a part of >> memory? >> >> Thank you~ >>