From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50455) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fXijt-0000Pn-04 for qemu-devel@nongnu.org; Tue, 26 Jun 2018 03:50:14 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fXijp-0000Tw-IM for qemu-devel@nongnu.org; Tue, 26 Jun 2018 03:50:13 -0400 Date: Tue, 26 Jun 2018 09:50:04 +0200 From: Cornelia Huck Message-ID: <20180626095004.7e92fdaa.cohuck@redhat.com> In-Reply-To: <54dfe708-cccf-c628-753f-692c83391ec4@redhat.com> References: <20180613151942.GC19901@redhat.com> <87k1r24quk.fsf@dusky.pond.sub.org> <20180619171539.0adc90d6.cohuck@redhat.com> <20180622181108.GY7451@localhost.localdomain> <20180622193522.GI7451@localhost.localdomain> <743d495e-51cd-8c8e-293e-026b8dece74a@redhat.com> <87lgb3xsv8.fsf@dusky.pond.sub.org> <4292432f-5f26-6925-4c14-ad1370e36e5b@redhat.com> <20180625173056.GM7451@localhost.localdomain> <97504b42-9ebe-45c5-6ff3-b43102c8374a@redhat.com> <54dfe708-cccf-c628-753f-692c83391ec4@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC PATCH 4/4] qemu-options: Do not show -enable-kvm and -enable-hax in the docs anymore List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Thomas Huth Cc: Paolo Bonzini , Eduardo Habkost , Markus Armbruster , zhang.zhanghailiang@huawei.com, Ben Warren , qemu-trivial@nongnu.org, qemu-devel@nongnu.org, Stefan Hajnoczi On Tue, 26 Jun 2018 06:40:56 +0200 Thomas Huth wrote: > On 25.06.2018 20:26, Paolo Bonzini wrote: > > On 25/06/2018 19:30, Eduardo Habkost wrote: > >>>> Attentive distros could even replace the wrapper script by a link. > >>> If they are okay with replacing the "KVM only" semantics with "KVM or > >>> TCG", which I think is generally worse. > >> > >> If we can't get agreement on what's the right default for each > >> QEMU binary, I think that's yet another reason to document that > >> upstream QEMU won't guarantee ABI compatibility if -accel is > >> omitted. > > > > Before that we should ask what the benefit is in changing the default > > for qemu-system-*. Nobody is using it in practice to start QEMU with > > KVM enabled... > > That's certainly not true. I've seen a couple of times already that > people ask on IRC why their guests are running so slow, and if you ask > them about their command line, it's obvious that they simply were not > aware of "-accel" / "-enable-kvm" yet. > > > Maybe we simply should add a "--verbose" command line option that people > can use to diagnose their problems: > > $ qemu-system-x86_64 --verbose > QEMU emulator version 2.12.50 > Using 'tcg' accelerator. Use '-accel kvm' to speed things up. > Machine type is 'pc-i440fx-3.0'. Use 'q35' for a more modern machine. > .... > Not sure how serious you meant that, but I actually quite like the idea :)