From mboxrd@z Thu Jan 1 00:00:00 1970 From: Binarus Subject: Re: Unable to pass multiple cores / CPUs to guests Date: Sat, 04 Feb 2012 10:03:21 +0100 Message-ID: <4F2CF459.9010302@binarus.de> References: <4F24FDBC.6000902@binarus.de> <20120130174445.GA23238@psychosis.jim.sh> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit To: kvm@vger.kernel.org Return-path: Received: from smtp-ssl.omeganet.de ([88.198.254.83]:44227 "EHLO smtp-ssl.omeganet.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752689Ab2BDJDZ (ORCPT ); Sat, 4 Feb 2012 04:03:25 -0500 Received: from [192.168.20.100] (p5DD17213.dip.t-dialin.net [93.209.114.19]) (authenticated bits=0) by smtp-ssl.omeganet.de (8.14.3/8.14.3/Debian-5+lenny1) with ESMTP id q1493MhU028562 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT) for ; Sat, 4 Feb 2012 10:03:23 +0100 In-Reply-To: <20120130174445.GA23238@psychosis.jim.sh> Sender: kvm-owner@vger.kernel.org List-ID: Jim, I just don't know how I could thank you! I have put multiple days into that problem and didn't remember nor see that I already have put -smp 1 later in the command. I think it would have cost me some more days or I would have been unable to solve the problem at all if you didn't give me that hint. It's working like expected now; the guest sees and uses the additional CPU core, and the backup from encrypted drives to other encrypted drives is running much faster and with lower CPU load now. An amusing aside: During my experiments, I had a set of parameters which made the Windows guest think it runs at 7.2 GHz (3 x 2.4 GHz where 2.4 GHz is the real clock rate of the host's CPU). Unfortunately, I can't remember the exact command, but I believe it roughly looked like ... -cpu qemu64 -smp2 ... -smp 1 ... Regards, Binarus On 30.01.2012 18:44, Jim Paris wrote: > Binarus wrote: >> Dear all, >> >> it seems that I am unable to pass multiple cores / CPUs to KVM >> guests. Whatever I do, the guests only report one CPU / core. > ... >> /usr/bin/qemu-system-x86_64 -M pc -cpu host -smp cores=2,threads=1,sockets=1 -drive file=/dev/sda6,if=virtio,cache=none,index=0 -drive file=/dev/sdb,if=virtio,cache=none,index=1 -cdrom /dev/cdrom -pidfile ./qemu-garak.pid -boot c -k de -m 4096 -smp 1 -device pci-assign,host=01:05.0 -daemonize -usb -usbdevice "tablet" -name garak -net nic,vlan=0,model=virtio,macaddr=02:01:01:01:01:01 -net tap,vlan=0,ifname=virtnet1,script=/etc/qemu-ifup,downscript=/etc/qemu-ifup -vnc :1 > > Remove the "-smp 1". > > -jim >