On 27 April 2015 at 16:30, Jan Kiszka <jan.kiszka@xxxxxxxxxxx> wrote:
but there is nothing yet (to my best knowledge) to avoid the exit on theToday, we have posted interrupts to avoid the vm-exit on the target CPU,
sender side (unless we ignore security). That's the same problem with
intra-guest IPIs, BTW.
For throughput and given NAPI patterns, that's probably not an issue as
you noted. It may be for latency, though, when almost every cycle counts.
Poll-mode networking applications (DPDK, Snabb Switch, etc) are typically busy-looping to poll the vring. They may have a very short usleep() between checks to save power but they don't wait on their eventfd. So for those particular applications latency is on the order of tens of microseconds even without guest exits.
_______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
