From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: cannot create VM with image on zfs filesystem (zfsonlinux) Date: Mon, 07 Nov 2011 17:22:41 +0200 Message-ID: <4EB7F7C1.9000005@redhat.com> References: <98E301E7-7879-46A4-871A-834F4C1529A1@yseda.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: "kvm@vger.kernel.org list" To: Peter Lees Return-path: Received: from mx1.redhat.com ([209.132.183.28]:63726 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751582Ab1KGPWn (ORCPT ); Mon, 7 Nov 2011 10:22:43 -0500 In-Reply-To: <98E301E7-7879-46A4-871A-834F4C1529A1@yseda.com> Sender: kvm-owner@vger.kernel.org List-ID: On 11/07/2011 03:57 PM, Peter Lees wrote: > hello all > > when trying to create a VM using a RAW image on a zfs filesystem, i get an > "invalid argument" error. > > has anyone made this work? is it a known issue and/or is there a workaround? > > > > > more detail: > > - i can create the VM on a ext4 filesystem > - i can create the VM on a ZFS zvol ("raw" device - too slow, however) > - linux is centos 6 (2.6.32-71.el6.x86_64 ) > - zfsonlinux is v0.6.0 (http://zfsonlinux.org) > - qemu-kvm is v0.12.1.2 ; release 2.113.el6_0.8 > - copying the VM disk from ext4fs to zfs & then running it results in a similar error > > > disk creation line was: > > # qemu-img create -f raw elveros_001.raw 15G > > > full error was: > Unable to complete install ' internal error Process exited while reading console log output: char device redirected to /dev/pts/3 > qemu: could not open disk image /space/vm_store/elveros_001.raw: Invalid argument I'm guessing that qemu tried to open the file with O_DIRECT, and zfsonlinux doesn't support O_DIRECT. Please try changing the cache mode to writeback. > any suggestions in getting ZFS as the vm_store, working with decent performance ? > zfsonlinux uses fuse, yes? I'd be surprised if you can get decent performance with it. -- error compiling committee.c: too many arguments to function