From mboxrd@z Thu Jan 1 00:00:00 1970 From: Markus Armbruster Subject: Re: [Qemu-devel] [PATCH v3 00/16] net: hub-based networking Date: Mon, 04 Jun 2012 09:24:18 +0200 Message-ID: References: <4FBF822D.9090707@redhat.com> <20120525100746.51d7bf28@doriath.home> <4FBF85BF.6050403@redhat.com> <20120525101830.1793d300@doriath.home> <4FBF86E0.7070908@redhat.com> <20120525103004.23cfc4f4@doriath.home> <4FBF8B0B.1090601@redhat.com> <20120525104322.2da0b0ba@doriath.home> <4FBF8D70.1030304@redhat.com> <20120525105628.1a1f3f8d@doriath.home> <20120528111704.GD30438@stefanha-thinkpad.localdomain> <20120528102551.2ffce963@doriath.home> <4FCC3E00.7080004@codemonkey.ws> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Stefan Hajnoczi , kvm@vger.kernel.org, jan.kiszka@siemens.com, qemu-devel@nongnu.org, Luiz Capitulino , zwu.kernel@gmail.com, wuzhy@linux.vnet.ibm.com, Stefan Hajnoczi , Paolo Bonzini To: Anthony Liguori Return-path: Received: from mx1.redhat.com ([209.132.183.28]:41969 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754542Ab2FDH27 (ORCPT ); Mon, 4 Jun 2012 03:28:59 -0400 In-Reply-To: <4FCC3E00.7080004@codemonkey.ws> (Anthony Liguori's message of "Mon, 04 Jun 2012 12:48:00 +0800") Sender: kvm-owner@vger.kernel.org List-ID: Anthony Liguori writes: > On 05/29/2012 04:14 PM, Markus Armbruster wrote: >> Luiz Capitulino writes: >> >>> On Mon, 28 May 2012 12:17:04 +0100 >>> Stefan Hajnoczi wrote: >>> >>>> What we need to decide is whether it's okay to drop QEMU "VLANs" >>>> completely and change dump command-line syntax? >>> >>> I'd vote for dropping it. >>> >>>> I think vlan-hub doesn't hurt anyone because the code has been isolated >>>> and we keep backwards compatibility. So I'd personally still go the >>>> vlan-hub route for QEMU 1.x. >>> >>> Just to make it clear: I'm not against this series. I'm against having >>> the functionality in qemu. If we want to keep the functionality, then I >>> completely agree that this series is the way to go. >> >> I agree with Luiz: if we want to reimplement that much of networking >> within QEMU, this series does it in a much better way than VLANs, but >> I'd rather not do it at all. >> >> Just advice, not a strong objection. > > Doesn't the same logic apply to reimplementing file systems? > Shouldn't we drop qcow3 in favor of using btrfs? btrfs isn't ready for production, so this is a hypothetical question. > It's easy to make the NIH argument when it's a feature you don't care about. > > A lot of people use vlans. It's the only way -net socket is useful > too. Just because most KVM/libvirt users don't doesn't mean they > aren't an important feature to preserve. I specifically asked for evidence on actual use of VLANs, and which uses of VLANs can't be readily upgraded to better-performing external solutions. You asserting it is used "a lot" isn't a full answer, but it's (slightly) better than nothing. > I would strongly nack any attempt to remove vlans w/o providing some > mechanism for backwards compatibility which is exactly what this patch > series does. Roma locuta, causa finita.