From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=32917 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Pmo1a-0001kS-TH for qemu-devel@nongnu.org; Tue, 08 Feb 2011 08:54:35 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Pmo1Z-0003lB-13 for qemu-devel@nongnu.org; Tue, 08 Feb 2011 08:54:34 -0500 Received: from mail-wy0-f173.google.com ([74.125.82.173]:38776) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Pmo1Y-0003kr-Ql for qemu-devel@nongnu.org; Tue, 08 Feb 2011 08:54:32 -0500 Received: by wyg36 with SMTP id 36so6001742wyg.4 for ; Tue, 08 Feb 2011 05:54:31 -0800 (PST) Message-ID: <4D51AD7D.6060709@codemonkey.ws> Date: Tue, 08 Feb 2011 14:54:21 -0600 From: Anthony Liguori MIME-Version: 1.0 Subject: Re: [Qemu-devel] Re: [PATCH 2/7] Enable I/O thread and VNC threads by default References: <4D3DFD20.8060004@linux.vnet.ibm.com> <20110125091741.GB30239@edde.se.axis.com> <20110125133453.GC5427@amt.cnet> <20110207101255.GA20413@amt.cnet> <20110207160350.GA26332@amt.cnet> <4D501C71.7090708@redhat.com> <4D50279B.5010102@siemens.com> <4D505DCB.9050406@codemonkey.ws> <20110207214551.GB16429@hall.aurel32.net> <4D50A5F0.802@codemonkey.ws> <20110208072657.GD16429@hall.aurel32.net> <4D50FA14.5010100@redhat.com> <4D5103E8.6050808@siemens.com> <4D510771.3040309@aurel32.net> <4D511221.9030505@siemens.com> <4D5113D3.9090802@aurel32.net> <4D511500.1040303@siemens.com> <4D5115C2.6060008@aurel32.net> <4D51842C.8000209@codemonkey.ws> <4D5125E2.8090902@aurel32.net> <4D5196DE.6030009@codemonkey.ws> <4D514558.9010003@aurel32.net> In-Reply-To: <4D514558.9010003@aurel32.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Aurelien Jarno Cc: Stefan Hajnoczi , Jan Kiszka , Marcelo Tosatti , "qemu-devel@nongnu.org" , Anthony Liguori , Paul Brook , Paolo Bonzini , "Edgar E. Iglesias" , Arun Bharadwaj On 02/08/2011 07:30 AM, Aurelien Jarno wrote: > So the strategy is let's break everything and wait for the maintainer to > fix that? This strategy doesn't work, we have seen for example that with > the SeaBIOS switch. While it brings nice features, it has broken the > isapc machine. And it's still not fixed... > The fundamental problem is that poorly thought out features have been committed in the past. isapc is a good example of this. You can't just remove a chipset but leave an ISA bus implementation and expect things to just keep working. Even the early ISA-only systems had a chipset that firmware interfaced with. > Also this strategy doesn't scale, then the maintainers are spending > their time fixing bugs introduced because others didn't care. Resources > are not unlimited, especially for those doing that on their free time. > So are you suggesting that every half baked feature should hold up any other future developments? I think the real problem is exactly the opposite of what you describe. Why should we waste finite resources keeping something like Windows support limping along? We need to do a better job of not adding features that there is no serious intention of every supporting in a meaningful way. I think the recent discussion of w64 is a good example of this. I can't imagine trying to support w64 in QEMU until someone actually makes w32 work in a reasonable way. >> I think we've fixed all that we're aware of but we probably won't find >> the rest unless we enable it universally. >> > I agree that we are going to discover bugs, and it's normal. QEMU is > quite complex and it's not possible to test every combination. That said > we are already aware of some bugs, why not fix them, or at least try to > fix them? For example we haven't fixed the performance regression with > TCG (at least it wasn't the case two weeks ago). > If there are known issues, yes, let's fix them before enabling it. Regards, Anthony Liguori