Datapath flows are created on demand, as packets with different relevant header fields arrive, and are also deleted if idle or if there are too many of them, so the "explosion" is controlled and typically minimal.
Jarno > On Oct 16, 2014, at 4:17 PM, Learner Study <learner.st...@gmail.com> wrote: > > Hi Jarno, > > But won't it cause flow-explosion issue when a single table replaces > multiple tables... > > I agree the userspace would merge all the rules from multiple tables > and provide a single entry which is good. But won't it lead to > explosion of flows that we see with OF 1.0...having multiple tables > was a big thing with OF 1.3... > > Could you point me to any more reading on this - if I am missing the > point here ;-) > > It would interesting to get opinion from HW offloads... > > Thanks! > Martin > >> On Wed, Oct 15, 2014 at 8:14 AM, Jarno Rajahalme <jrajaha...@nicira.com> >> wrote: >> OVS userspace translates the multiple OpenFlow tables a packet traverses to >> a single kernel flow table entry. This way the following packets hitting the >> same kernel flow only need one flow table lookup, even though there were >> multiple OpenFlow tables. >> >> So the answer to your question is that yes, OVS kernel module supports >> multiple OpenFlow tables, but your assumption that this would require >> multiple kernel flow tables is wrong. >> >> Some flows (e.g., ones with MPLS pop action) need "recirculation", that is, >> multiple rounds through the single kernel flow table, but also this is >> invisible to the OpenFlow controller. >> >> Hope this helps, >> >> Jarno >> >> >>> On Oct 15, 2014, at 12:55 AM, Learner Study <learner.st...@gmail.com> wrote: >>> >>> Hi, >>> >>> Does OVS-2.x support multiple table in kernel or is it just in user space? >>> If only in user-space, is there a reason not to move it to kernel fast path? >>> >>> Thanks >>> Martin >>> _______________________________________________ >>> dev mailing list >>> dev@openvswitch.org >>> http://openvswitch.org/mailman/listinfo/dev _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
