On Mon, Jul 9, 2018 at 6:58 PM, Michael S. Tsirkin <m...@redhat.com> wrote: > On Mon, Jul 09, 2018 at 06:11:53PM -0700, si-wei liu wrote: >> What do we buy >> for using a random address during initial discovery and requiring VF to >> complete the handshake? > > I don't see advantages to using a random address that is then > changed either: changing a MAC causes network downtime for most users. > Definitely.
I see Linux host stack fundamentally different with Windows, it's non-sense to duplicate what Hyper-V is doing especially if there's no extra benefit. >> Less network downtime during datapath switching? >> Sorry but that's not a key factor at all for our main goal - live migration. > > Isn't avoiding downtime what makes the migration "live"? > If you don't care about it at all just remove the device > and migrate without all these tricks. Apparently this downtime is not avoidable even if guest initiates the switch-over when it is done on Linux host stack. Unless the NIC supports adding duplicate MAC filters with one has higher priority than the other when both are present. I feel there's very little or perhaps zero improvement for the downtime if moving to a guest-initiated datapath switching model. However, since this downtime is intermittent and generally unnoticeable with a few packet drops, network should be resilient in recovering from the drops. My point is that unless we can move to a datapath switching model with zero downtime theoretically, this kind of minor optimization offers very little help in general. Regards, -Siwei > > > -- > MST > > --------------------------------------------------------------------- > To unsubscribe, e-mail: virtio-dev-unsubscr...@lists.oasis-open.org > For additional commands, e-mail: virtio-dev-h...@lists.oasis-open.org >
