That's what I think we should clarify. That's why I ask about priority. There is some inconsistency. Apparently in OpenFlow v1.1, this is inconsistency will be gone, so priority should be perserved.
Regards KK PS>> Think this is best done on openflow-spec. On 21 February 2011 18:11, Derek Cormier <derek.corm...@lab.ntt.co.jp> wrote: > On page 14 of the spec, it says that if _STRICT is used, all fields, > including the wildcards and priority, are strictly matched against the > entry, and only an identical flow is modified or removed. > > - Derek > > On 02/22/2011 11:04 AM, kk yap wrote: >> >> Hi Derek, >> >> Actually priority for exact match does not matter. So, there cannot >> be two different exact match flow entries that only differ by >> priority up till at least OpenFlow 1.0. That's the case I was thinking >> about. >> >> Regards >> KK >> >> On 21 February 2011 17:54, Derek Cormier<derek.corm...@lab.ntt.co.jp> >> wrote: >>> >>> Hi KK, >>> >>> Thanks for posting this to the openflow-spec board. I do think the >>> priority >>> should be maintained since two identical flow matches can exist with >>> different priorities. If one of them is removed, it could be useful to >>> know >>> which one. To identify a flow uniquely, I believe you need the ofp_match& >>> priority (unless a cookie is used). >>> >>> - Derek >>> >>> On 02/22/2011 03:27 AM, kk yap wrote: >>>> >>>> Hi, >>>> >>>> I believe maintaining the wildcards would be enough. To me, the >>>> following two matches are the same: >>>> >>>> Wildcards = ALL - DL_TYPE, DL_TYPE = 5, IP_SRC = 100... >>>> Wildcards = ALL - DL_TYPE, DL_TYPE = 5, IP_SRC = 0... >>>> >>>> I believe Ben and Justin is saying that it is reasonable to maintain >>>> the wildcard field. Seems like we have a working solution? >>>> >>>> I will post this on the openflow-spec list for the words to be cleared >>>> up. The priority field worries me a little more, such I think exact >>>> match is normalized to priority 65535? Should that be maintained in >>>> flow_removed? I wonder. >>>> >>>> Regards >>>> KK >>>> >>>> On 21 February 2011 09:30, Ben Pfaff<b...@nicira.com> wrote: >>>>> >>>>> On Sun, Feb 20, 2011 at 11:36 PM, Derek Cormier >>>>> <derek.corm...@lab.ntt.co.jp> wrote: >>>>>> >>>>>> I see what you mean and I agree that a switch shouldn't store >>>>>> unnecessary >>>>>> information. But is it really a burden in this case? The wildcards are >>>>>> stored in a single 32-bit integer, so no extra space is needed. >>>>> >>>>> The data structure that OVS uses for classification requires that >>>>> wildcarded fields >>>>> be zeroed for efficiency reasons. In other words, storing the >>>>> wildcards >>>>> isn't a >>>>> big deal, but storing nonzero values of wildcarded fields would require >>>>> extra >>>>> memory. So I'd rather not do it, although certainly it's not a huge >>>>> deal if in the >>>>> OVS has to. >>>>> >>>>> _______________________________________________ >>>>> discuss mailing list >>>>> discuss@openvswitch.org >>>>> http://openvswitch.org/mailman/listinfo/discuss_openvswitch.org >>>>> >>> >> > > _______________________________________________ discuss mailing list discuss@openvswitch.org http://openvswitch.org/mailman/listinfo/discuss_openvswitch.org
