Thanks Paolo for your clarification! Just wanted to double confirm, does this mean batch I/O submission won't apply to aio=threads (which is the default mode)?
Thanks, Wei On 4/26/19, 9:25 PM, "Paolo Bonzini" <pbonz...@redhat.com> wrote: > Thanks Stefan and Paolo for your response and advice! > > Hi Paolo, > > As to the virtio-scsi batch I/O submission feature in QEMU which you > mentioned, is this feature turned on by default in QEMU 2.9 or there is a > tunable parameters to turn on/off the feature? Yes, it is available by default since 2.2.0. It cannot be turned off, however it is only possible to batch I/O with aio=native (and, since 2.12.0, with the NVMe backend). Paolo