On Fri, Sep 22, 2023 at 11:02:50AM +0800, Jason Wang wrote: > On Fri, Sep 22, 2023 at 3:53 AM Jason Gunthorpe <jgg@xxxxxxxxxx> wrote: > > > > On Thu, Sep 21, 2023 at 03:34:03PM -0400, Michael S. Tsirkin wrote: > > > > > that's easy/practical. If instead VDPA gives the same speed with just > > > shadow vq then keeping this hack in vfio seems like less of a problem. > > > Finally if VDPA is faster then maybe you will reconsider using it ;) > > > > It is not all about the speed. > > > > VDPA presents another large and complex software stack in the > > hypervisor that can be eliminated by simply using VFIO. > > vDPA supports standard virtio devices so how did you define > complexity? As I said, VFIO is already required for other devices in these VMs. So anything incremental over base-line vfio-pci is complexity to minimize. Everything vdpa does is either redundant or unnecessary compared to VFIO in these environments. Jason
