From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: 64 bit guest much faster ? Date: Mon, 26 Oct 2009 12:44:30 +0200 Message-ID: <4AE57D8E.7090506@redhat.com> References: <4AE1D1A4.6050001@pms.ifi.lmu.de> <4AE564C6.3040605@redhat.com> <4AE575FD.6010801@redhat.com> <4AE57D04.10408@msgid.tls.msk.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Cc: Gerd Hoffmann , Stefan , kvm@vger.kernel.org To: Michael Tokarev Return-path: Received: from mx1.redhat.com ([209.132.183.28]:10678 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755539AbZJZKog (ORCPT ); Mon, 26 Oct 2009 06:44:36 -0400 In-Reply-To: <4AE57D04.10408@msgid.tls.msk.ru> Sender: kvm-owner@vger.kernel.org List-ID: On 10/26/2009 12:42 PM, Michael Tokarev wrote: >> Oh yes, without ept/npt the slowdown should indeed be significant >> with this much memory. > > > How it is with 4Gb guest/mem without PAE (I mean, with > CONFIG_HIGHMEM_4G=y)? > Or even 2Gb? In case of npt or without. > It'll be slow. Just use x86_64 with > 1GB. > Can we construct a sort of a table of expected slowdowns (not in numbers > but just in terms "significant", "minor" etc) of running <4Gb or >4Gb > (and <1Gb and >1Gb if that makes significant diffencece) 32bit guests > with and without npt and 64bit guests, please? I guess it's quite > interesting to many users. These tables will be useless, it greatly depends on workload. -- error compiling committee.c: too many arguments to function