I'm planning to use iSCSI targets (over gigabit VLANs) for KVM guest disks. The question I'm wondering about is whether it's better to md (multi-path + mirror) the iSCSI targets on the host, then create LVM partitions for the guests. Or to directly md the iSCSI targets within the guest. On one hand I think it would be slower to process the additional layers in the guest, but on the other hand, readings seems to indicate that the kernel is able to perform better disk i/o if it's aware of multiple disks rather than just seeing a single disk. I've not been able to find any definitive article/data on how these might balance out. Would anybody in the list have a good idea which way is better in terms of i/o performance? -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
