Stefan Hajnoczi <stefanha@xxxxxxxxx> wrote on 03/09/2011 05:12:07 AM: > > 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. Yes, for I/O-intensive workloads on fast storage systems, I've found that the deadline scheduler works best. Thanks, -Khoa -- 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
