From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f175.google.com (mail-wi0-f175.google.com [209.85.212.175]) by dpdk.org (Postfix) with ESMTP id 460868DA6 for ; Thu, 1 Oct 2015 07:04:06 +0200 (CEST) Received: by wicge5 with SMTP id ge5so11591011wic.0 for ; Wed, 30 Sep 2015 22:04:06 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-type:content-disposition:in-reply-to; bh=nP0IeYxNtWDDXwdkOnxBv4vZPeybOuygCj0NP4TGlg8=; b=Efdl0dgueAjN8mxpkqyRhT5zpEzeQ9NwVx37w3NY7uzydLSgEVrflWPpBJycttencu v6I6cC6BBoGBhwp6alEEZQIrHN8uMcLEeWLiet+FmehqVimcs3Q0vm+XYpJRlMJCtK5p HO+DX1JSb82PQdocL06PPmE9FIO1LL5L9/UH0OEquKbl1wz9V3qKsdOcVtdIMMCM0zcx 10ADXSMI3LPm8+XGYtubW1/TgkL5rupzSmTTeCp8R52Hy0px4SpW0InVV0BPaI3+kDqN cyFxTYpX9zaP/RMXTlPNh8FL5V1KYeJCoDl5GIJfCzhA4UNbqozGghLP2teP14POOIMJ +xsw== X-Gm-Message-State: ALoCoQmJ04g/zNgkV6XigSgijiMthf7TJwExRSY1nFfAv+N8SunPZ+/hnVHfaaXMEsxtIRSzEUt+ X-Received: by 10.194.48.81 with SMTP id j17mr7849340wjn.81.1443675846110; Wed, 30 Sep 2015 22:04:06 -0700 (PDT) Received: from trex.cloudius-systems.com (bzq-84-111-155-225.red.bezeqint.net. [84.111.155.225]) by smtp.gmail.com with ESMTPSA id w1sm4000369wjz.37.2015.09.30.22.04.04 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 30 Sep 2015 22:04:05 -0700 (PDT) Received: by trex.cloudius-systems.com (Postfix, from userid 1042) id 2844A83F52; Thu, 1 Oct 2015 08:04:03 +0300 (IDT) Date: Thu, 1 Oct 2015 08:04:03 +0300 From: Gleb Natapov To: "Michael S. Tsirkin" Message-ID: <20151001050403.GD27881@scylladb.com> References: <20150929235122-mutt-send-email-mst@redhat.com> <20150929144616.4e70b44c@urahara> <20150930004714-mutt-send-email-mst@redhat.com> <560BBB62.3050502@cloudius-systems.com> <20150930102807.6e681bca@urahara> <20150930203712-mutt-send-email-mst@redhat.com> <20150930104304.7a8c8e56@urahara> <20150930212553-mutt-send-email-mst@redhat.com> <20150930200049.GC27881@scylladb.com> <20150930232841-mutt-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150930232841-mutt-send-email-mst@redhat.com> Cc: "dev@dpdk.org" Subject: Re: [dpdk-dev] Having troubles binding an SR-IOV VF to uio_pci_generic on Amazon instance X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 01 Oct 2015 05:04:06 -0000 On Wed, Sep 30, 2015 at 11:36:58PM +0300, Michael S. Tsirkin wrote: > On Wed, Sep 30, 2015 at 11:00:49PM +0300, Gleb Natapov wrote: > > > You are increasing interrupt latency by a huge factor by channeling > > > interrupts through a scheduler. Let user install an > > > interrupt handler function, and be done with it. > > > > > Interrupt latency is not always hugely important. If you enter interrupt > > mode only when idle hundred more us on a first packet will not kill you. > > It certainly affects worst-case latency. And if you lower interupt > latency, you can go idle faster, so it affects power too. > We are polling 100% now. Going idle faster is the least of our concern. > > If > > interrupt latency is important then uio may be not the right solution, > > but then neither is vfio. > > That's what I'm saying, if you don't need memory isolation you can do > better than just slightly tweak existing drivers. > No, you are forcing everyone to code in kernel no matter if it make sense or not. You decide for everyone what is good for them. Believe me people here know about trade-offs and made appropriate considerations. -- Gleb.