From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=56795 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OMN2T-0003jz-0F for qemu-devel@nongnu.org; Wed, 09 Jun 2010 11:17:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OMN2R-0006lL-Ao for qemu-devel@nongnu.org; Wed, 09 Jun 2010 11:17:56 -0400 Received: from mx1.redhat.com ([209.132.183.28]:20677) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OMN2R-0006kx-3N for qemu-devel@nongnu.org; Wed, 09 Jun 2010 11:17:55 -0400 Message-ID: <4C0FB09E.1080604@redhat.com> Date: Wed, 09 Jun 2010 18:17:50 +0300 From: Avi Kivity MIME-Version: 1.0 References: <4C0E3C46.30901@dlh.net> <4C0E3CD5.4070202@redhat.com> <4C0E4576.8030609@dlh.net> <4C0E46ED.5030305@redhat.com> <4C0E47C3.1050409@dlh.net> <4C0E484D.4060609@redhat.com> <4C0E492F.6060203@dlh.net> <4C0E495C.8020008@redhat.com> <4C0F50ED.7060109@dlh.net> <4C0FAE67.3010002@redhat.com> <20100609151214.GC14316@redhat.com> In-Reply-To: <20100609151214.GC14316@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Re: Live Migration of 32-bit Linux guest broken since 2.6.35-rc2 List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gleb Natapov Cc: Peter Lieven , qemu-devel@nongnu.org, kvm@vger.kernel.org On 06/09/2010 06:12 PM, Gleb Natapov wrote: > >>> a) i remember that there (have been) are instructions that have a >>> high virtualization penalty. >>> are there flags that should better not be offered to a VM? >>> >> Not that I know of. >> >> > rdtscp? I think it's always emulated. > No, it executes natively. It does increase the msr switching cost since we need to switch MSR_TSC_AUX in addition. -- error compiling committee.c: too many arguments to function