On Fri, Feb 3, 2017 at 1:34 PM, Rick Jones <rick.jon...@hpe.com> wrote: > On 02/03/2017 10:31 AM, Willem de Bruijn wrote: >> >> Configuring interrupts and xps from userspace at boot is more robust, >> as device driver defaults can change. But especially for customers who >> are unaware of these settings, choosing sane defaults won't hurt. > > > The devil is in finding the sane defaults.
Agreed, of course. > For example, the issues we've > seen with VMs sending traffic getting reordered when the driver took it upon > itself to enable xps. That particular reordering issue [1] was with xps on the host, where vm thread migration causes flows to exit on different tx queues because ooo_okay is not supported for flows from tap devices. Within a guest, on the other hand, xps settings should not cause reordering of packets from the same flow, as ooo_okay is active for tcp flows. [1] https://patchwork.ozlabs.org/patch/662913/
