From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <ramirose@gmail.com>
Received: from mail-wr1-f41.google.com (mail-wr1-f41.google.com
 [209.85.221.41]) by dpdk.org (Postfix) with ESMTP id B01D45B2A
 for <dev@dpdk.org>; Mon,  4 Feb 2019 13:19:30 +0100 (CET)
Received: by mail-wr1-f41.google.com with SMTP id s12so14157735wrt.4
 for <dev@dpdk.org>; Mon, 04 Feb 2019 04:19:30 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025;
 h=mime-version:references:in-reply-to:from:date:message-id:subject:to
 :cc; bh=SxrCUTAqKm1e6xBkLRueKNhLrr9fw8yUb8thmOVWNRU=;
 b=ixqH2zdmDKeHUFjVOwJajxa/J8/xiwnELxFsvzZ6kxAxrc5nd2xIrlKu7Gc2V5sGPO
 GczoUPR4JX85OARitFh+a4yYG1ozilpDU1Bd56JVDPGFT5fzYjdUaHQlZ0sq00pFkMmP
 SBdtdZgBkR5vST4SbZnrolWfds+VEwvswO8b5KHBZLZkNcYFsRddpHQopR4g8j+c8Uuf
 NGrINW8HXL+L+y6DzxfEjaeCsRBHOSW8Pm4NXFtq5WUMvY5zShJuF4qMG03iuE+YlwHa
 SR/eBm9veLPHzboUZDSkn07gZEjK7IG9puUjzQkskvRgnOrARbxIQ38NMcalXTj4RY41
 t2Kg==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=1e100.net; s=20161025;
 h=x-gm-message-state:mime-version:references:in-reply-to:from:date
 :message-id:subject:to:cc;
 bh=SxrCUTAqKm1e6xBkLRueKNhLrr9fw8yUb8thmOVWNRU=;
 b=r7Ksujgj+hCloptbs9WuwaZDIpGbFCn+IrBk91HzC8dQAyVZLsQDVNBZhfT98c9yVF
 E1+W6mEGqGVntIpLRLaOzvvgamEhWg505rbd47ZizcEOdFq/R3AdQuhxP+hhNZ3jvxfO
 mdNDou/ED4TB8+9IYDka1rDpqxXuI3X2gIi4q5lwdmDYGtpec4pnG8sBXy0AU+2gJ7OO
 6R0oG6QL1BipPSTr28D0zzEX67MOB9FDmPaxQbEKBteVpcOWg225ZHZxAX/+p1gmJG7i
 Ct5uiV5i2CJG/iRsxmXclcg7Q957LOlVip9qj/SHP3ftXkfyYBWuF8fayQu7TzsyKZ1t
 vdYQ==
X-Gm-Message-State: AJcUukfFvzl8Ftyloi+dBYAEfC4ei8ctY0J6zspyPwlsrrTKmFNWY7l/
 8mmjzsKc345WLiOuGvHD7IMflvDBZ9+AgBwo6kc=
X-Google-Smtp-Source: ALg8bN7IFaAwmh9pW3DeIqW0GC8veC+UP5PXSIEaFt2S9YxyJVFATPS/2rF1NneDRHURD1EyWVJ1s5O45l2unzwTp6I=
X-Received: by 2002:adf:ea11:: with SMTP id q17mr46985010wrm.328.1549282770173; 
 Mon, 04 Feb 2019 04:19:30 -0800 (PST)
MIME-Version: 1.0
References: <CAHLOa7SnR+4hDzVPuEnTXPxCxurbqXGinP9jCk8XzjEWkiSEYw@mail.gmail.com>
 <CAD+H992VV2hmkhi1D250+ucN2O4ZY6G5-phKuNMmSG1qekzuBw@mail.gmail.com>
 <CAHLOa7RSXHGL8YpHXu5U1WOAh2uK0w9fnh8Eg_jB3dW5SdxKZg@mail.gmail.com>
 <CAD+H991KfTXwLSu4fco9W26m8LPqnQaYAG5k5yY-SUBjMigDDQ@mail.gmail.com>
In-Reply-To: <CAD+H991KfTXwLSu4fco9W26m8LPqnQaYAG5k5yY-SUBjMigDDQ@mail.gmail.com>
From: Rami Rosen <ramirose@gmail.com>
Date: Mon, 4 Feb 2019 14:19:19 +0200
Message-ID: <CAHLOa7Qq97=QFyiF-WmAZbYE+bj_aDNxXcBC+Tx-8CDj9mrLjw@mail.gmail.com>
To: Alejandro Lucero <alejandro.lucero@netronome.com>
Cc: dev <dev@dpdk.org>
Content-Type: text/plain; charset="UTF-8"
X-Content-Filtered-By: Mailman/MimeDel 2.1.15
Subject: Re: [dpdk-dev] A Question about the necessity of DPDK VF for
	Ethernet PMDs
X-BeenThere: dev@dpdk.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: DPDK patches and discussions <dev.dpdk.org>
List-Unsubscribe: <https://mails.dpdk.org/options/dev>,
 <mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://mails.dpdk.org/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <https://mails.dpdk.org/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
X-List-Received-Date: Mon, 04 Feb 2019 12:19:30 -0000

Hi, Alejandro,

Thanks for you quick response.

>When SRIOV is used by VMs, the slow path will always be faster (and
>with lower latency) with DPDK.

Yes, I am referring primarily to the SRIOV case in my question, when
assigning PCI VF to a VM (most likely QEMU VM)
Can you please explain what you mean about slow path in this context ?

Not sure the OVS setup is relevant here, it seems (if I understand
correctly) that VFIO is more commonly used in OVS setups,
so this query is not relevant here (unless you use igb_uio which is less
common)
According to
http://docs.openvswitch.org/en/latest/intro/install/dpdk/
"VFIO is prefered to the UIO driver when using recent versions of DPDK. "
Regards,
Rami Rosen