Looks like even upstream suggests disabling cache for best performance when using raw volumes: http://www.linux-kvm.org/page/Tuning_KVM
>From the above page: QEMU also supports a wide variety of caching modes. Writeback is useful for testing but does not offer storage guarantees. Writethrough (the default) is safer, and relies on the host cache. If you're using raw volumes or partitions, it is best to avoid the cache completely, which reduces data copies and bus traffic: qemu -drive file=/dev/mapper/ImagesVolumeGroup- Guest1,cache=none,if=virtio -- LVM backed drives should default to cache='none' https://bugs.launchpad.net/bugs/568445 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
