From owner-freebsd-net@FreeBSD.ORG Wed May 22 19:08:38 2013 Return-Path: Delivered-To: net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id 8CCB6104 for ; Wed, 22 May 2013 19:08:38 +0000 (UTC) (envelope-from rysto32@gmail.com) Received: from mail-ob0-x22c.google.com (mail-ob0-x22c.google.com [IPv6:2607:f8b0:4003:c01::22c]) by mx1.freebsd.org (Postfix) with ESMTP id 51CA1F94 for ; Wed, 22 May 2013 19:08:38 +0000 (UTC) Received: by mail-ob0-f172.google.com with SMTP id tb18so2884368obb.17 for ; Wed, 22 May 2013 12:08:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=dh6uJ1JpyUnEa6jv9B4knZaTo3aq496zn44X3ESl0xM=; b=TzShzo1PrmW8LTF7ouPVYfsKnPf5HW3RkNATYU0aS3WCsU7lKWc3AlIrlsfx8Y/UDe fd15luS14yQDIQWbBw7ralPyEEZE+oxBpw2QjsjPK7BhlZH9HR3zV6a47rdXoSjl1IVS Wvek7yIvQCMtr/8f+WSk448wIoF4BedSCyRhVEvZmvUvIIMKlgMnQYadX4miCJ6yqhL+ CefZ2wygCrAAsI6GVdft2vcn2/RBd8jF+T9tm2++DFUgNNhMnuaWTYyduA/v5bCibW9t M0FwyYh/kXyTjygiF2C7beCs++EMNqB7yWO8ZlHCaMQKT6SgwcNFlekU4VnfLECAeVwF yEKg== MIME-Version: 1.0 X-Received: by 10.60.131.6 with SMTP id oi6mr5879458oeb.19.1369249717783; Wed, 22 May 2013 12:08:37 -0700 (PDT) Received: by 10.76.90.10 with HTTP; Wed, 22 May 2013 12:08:37 -0700 (PDT) In-Reply-To: <20130522164244.GB95808@onelab2.iet.unipi.it> References: <20130522164244.GB95808@onelab2.iet.unipi.it> Date: Wed, 22 May 2013 15:08:37 -0400 Message-ID: Subject: Re: surprise surprise (VM related) [luigi@FreeBSD.org: svn commit: r250911 - head/sys/kern] From: Ryan Stone To: Luigi Rizzo Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.14 Cc: FreeBSD Net X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 22 May 2013 19:08:38 -0000 On Wed, May 22, 2013 at 12:42 PM, Luigi Rizzo wrote: > all that work on paravirtualization (as presented at bsdcan) > > http://info.iet.unipi.it/~luigi/netmap/talk-bsdcan-2013.html > > just to discover that simply enabling DEVICE_POLLING (10-years old > technology) gives the same performance gains plus livelock-avoidance. > > And no, linux's NAPI is nowhere near us. > > cheers > luigi > A couple of years ago I started working on upstreaming some DEVICE_POLLING improvements from $WORK that incorporated feedback from polled interfaces to drive rescheduling of a polling iteration (rather than waiting for the next hardclock() to reschedule polling) but I never finished it. It works fine, but I didn't get a chance to test performance. It's available here: https://gitorious.org/~rysto/freebsd/rystos-freebsd-head/commit/e27db681b96cced7d3128ad3268f2cbf7474925a In the same repository I also have a branch that extends DEVICE_POLLING to work with multiple netisr threads.