From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: [PATCH 0 of 2] Remove --disable-cpu-emulation for qemu Date: Wed, 18 Jun 2008 15:56:45 -0500 Message-ID: <4859768D.3020809@codemonkey.ws> References: <48590B58.4010005@qumranet.com> <48590BA3.9050901@qumranet.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Jerone Young , kvm@vger.kernel.org, kvm-ppc@vger.kernel.org To: Avi Kivity Return-path: Received: from yx-out-2324.google.com ([74.125.44.29]:8668 "EHLO yx-out-2324.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755520AbYFRU52 (ORCPT ); Wed, 18 Jun 2008 16:57:28 -0400 Received: by yx-out-2324.google.com with SMTP id 31so81887yxl.1 for ; Wed, 18 Jun 2008 13:57:27 -0700 (PDT) In-Reply-To: <48590BA3.9050901@qumranet.com> Sender: kvm-owner@vger.kernel.org List-ID: Avi Kivity wrote: > Avi Kivity wrote: >> Jerone Young wrote: >>> These patches remove all traces of --disable-cpu-emulation >>> configuration flag. >>> >>> >> >> I kind of like --disable-cpu-emulation. It means we have the choice >> of kvm-only (low footprint, shuts up the security people), qemu-only >> (running cross-arch or on older cpu), and mixed mode (I'm a distro >> so don't know what cpu I'm running on). >> >> Well, actually, at least Fedora already supplies both plain qemu and >> qemu-kvm, so it seems they don't care much about mixed mode. I'll >> look at applying the patches. >> > > Er, that only makes sense with Anthony's idea of a -kvm subtarget > thrown in as well. The -kvm subtarget is really easy to implement. If anyone is interested in doing this, let me know and I'll point them in the right direction. The good thing about a -kvm subtarget is that we can introduce a CONFIG_KVM_ONLY #define which we can use to compile out l1_phys_map et al. That will give a much better RSS reduction than not linking in TCG. I doubt --disable-cpu-emulation really reduces RSS size an observable amount. Regards, Anthony Liguori