Thanks Carl. This was the direction/experience I was looking for. I always felt that running a complex file system like backuppc's on a virtualized file system would have additional performance implications. I went ahead and tried it and had issues. Using the virtio driver just makes more sense to me. It also allows for better portability of the VM for backuppc.
David Trebacz Email: [email protected] Tel: 815-344-9068 Mobile: 815-529-2638 On 01/03/2014 09:46 AM, Carl Cravens wrote: > The VM isn't an issue (my BackupPC has run in a KVM guest for over two > years), but using "file-based" storage (a filesystem inside a file stored on > another filesystem) is extremely inefficient (we recently ran benchmarks on > file versus raw device... the performance is awful in comparison). > > Use a raw device (raw disk, LVM volume, etc) with the virtio driver. Your OS > and backup storage can reside on the same raw device, or they can be separate > raw devices, or if you insist, the OS can be virtual file storage. We just > use raw devices (LVM logical volumes) for everything. > > My disk configuration looks like this (virsh dumpxml <guestname>): > > <disk type='block' device='disk'> > <driver name='qemu' type='raw'/> > <source dev='/dev/diskbackup/diskbackup'/> > <target dev='vda' bus='virtio'/> > <alias name='virtio-disk0'/> > <address type='pci' domain='0x0000' bus='0x00' slot='0x04' > function='0x0'/> > </disk> > > "/dev/diskbackup/diskbackup" is a logical volume named "diskbackup" in a > volume group named "diskbackup". (I didn't configure this... traditionally, > this would be "/dev/vgdiskbackup/lvdiskbackup" or such.) > ------------------------------------------------------------------------------ Rapidly troubleshoot problems before they affect your business. Most IT organizations don't have a clear picture of how application performance affects their revenue. With AppDynamics, you get 100% visibility into your Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics Pro! http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk _______________________________________________ BackupPC-users mailing list [email protected] List: https://lists.sourceforge.net/lists/listinfo/backuppc-users Wiki: http://backuppc.wiki.sourceforge.net Project: http://backuppc.sourceforge.net/
