> I'll add 'in_decay' flag and set bfd->min_rx to decay_min_rx, when receiving > the FINAL packet.
It should be sufficient to set bfd->poll_min_rx to the appropriate value in the bfd_poll() function. The poll_min_rx is automatically copied to the min_rx field when the FINAL packet comes in. Ethan > > > On Mon, Aug 5, 2013 at 3:35 PM, Ethan Jackson <et...@nicira.com> wrote: >> >> On Mon, Aug 5, 2013 at 2:04 PM, Alex Wang <al...@nicira.com> wrote: >> > When there is no incoming data traffic at the interface for a period, >> > BFD decay allows the bfd session to increase the min_rx. This is >> > helpful in that some interfaces usually idle for long time. And cpu >> > consumption can be reduced by processing fewer bfd control >> >> "interaces usually" => "interfaces are usually" or "interfaces may be" >> >> "for long" => "for a long" >> >> There's one major issue with this patch. In several places, it >> directly sets bfd->min_rx to either bfd->decay_min_rx or >> bfd->cfg_min_rx. This is very much not allowed. We have to give the >> remote BFD session a chance to react to the fact that we're changing >> our min_rx before we actually change it, otherwise it won't be sending >> control packets quickly enough and we'll have flaps. >> >> I think we should add a flag to in_decay which is set to true if decay >> mode has triggered and false if not. This line of code in bfd_poll() >> should change: >> >> bfd->poll_min_rx = bfd->min_rx == bfd->decay_min_rx >> ? bfd->decay_min_rx : bfd->cfg_min_rx; >> >> to >> >> bfd->poll_min_rx = bfd->in_decay ? bfd->decay_min_rx >> : bfd->cfg_min_rx >> >> Then whenever the configuration changes, or we move from in_decay = >> false to in_decay = true, we can call bfd_poll() and know that the >> transition to the new min_rx value will happen safely. I think that >> would also simplify the patch quite a bit. >> >> Ethan > > X-CudaMail-Whitelist-To: dev@openvswitch.org _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
