On Wed, Mar 9, 2011 at 10:01 AM, Avi Kivity <avi@xxxxxxxxxx> wrote: > On 03/09/2011 11:42 AM, Harald Dunkel wrote: >> >> Hi folks, >> >> would it make sense to make elevator=noop the default >> for virtio block devices? Or would you recommend to >> set this on the kvm server instead? >> > > I think leaving the defaults is best. The elevator on the guest serves to > schedule I/O among processes in the guest, and the elevator on the host > partitions I/O among the guests. It depends on the workload. Khoa has seen cases where CFQ does not scale with multi-threaded workloads and deadline is preferred. But it's not one-size-fits-all, it depends on your workload and requires benchmarking. Stefan -- 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
