From: Ben Pfaff Date: Mon, 6 Feb 2012 18:40:10 +0000 (-0800) Subject: DESIGN: Document the properties of flow_mods. X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=12442ec572f794b93aa47fbeb9a73974acc2bac3;p=openvswitch DESIGN: Document the properties of flow_mods. I'm tired of trying to figure these out all over again each time I think about it. Signed-off-by: Ben Pfaff --- diff --git a/DESIGN b/DESIGN index c53a8ea3..164ada20 100644 --- a/DESIGN +++ b/DESIGN @@ -20,6 +20,77 @@ to 'internal' ports whose port numbers are less than OFPP_MAX, we interpret OFPP_LOCAL as a physical port and support OFPAT_ENQUEUE on it as well. +OFPT_FLOW_MOD +============= + +The OpenFlow 1.0 specification for the behavior of OFPT_FLOW_MOD is +confusing. The following table summarizes the Open vSwitch +implementation of its behavior in the following categories: + + - "match on priority": Whether the flow_mod acts only on flows + whose priority matches that included in the flow_mod message. + + - "match on out_port": Whether the flow_mod acts only on flows + that output to the out_port included in the flow_mod message (if + out_port is not OFPP_NONE). + + - "updates flow_cookie": Whether the flow_mod changes the + flow_cookie of the flow or flows that it matches to the + flow_cookie included in the flow_mod message. + + - "updates OFPFF_ flags": Whether the flow_mod changes the + OFPFF_SEND_FLOW_REM flag of the flow or flows that it matches to + the setting included in the flags of the flow_mod message. + + - "honors OFPFF_CHECK_OVERLAP": Whether the OFPFF_CHECK_OVERLAP + flag in the flow_mod is significant. + + - "updates idle_timeout" and "updates hard_timeout": Whether the + idle_timeout and hard_timeout in the flow_mod, respectively, + have an effect on the flow or flows matched by the flow_mod. + + - "updates idle timer": Whether the flow_mod resets the per-flow + timer that measures how long a flow has been idle. + + - "updates hard timer": Whether the flow_mod resets the per-flow + timer that measures how long it has been since a flow was + modified. + + - "zeros counters": Whether the flow_mod resets per-flow packet + and byte counters to zero. + + - "sends flow_removed message": Whether the flow_mod generates a + flow_removed message for the flow or flows that it affects. + +An entry labeled "yes" means that the flow mod type does have the +indicated behavior, "---" means that it does not, an empty cell means +that the property is not applicable, and other values are explained +below the table. + + MODIFY DELETE + ADD MODIFY STRICT DELETE STRICT + === ====== ====== ====== ====== +match on priority --- --- yes --- yes +match on out_port --- --- --- yes yes +updates flow_cookie yes yes yes +updates OFPFF_SEND_FLOW_REM yes + + +honors OFPFF_CHECK_OVERLAP yes + + +updates idle_timeout yes + + +updates hard_timeout yes + + +resets idle timer yes + + +resets hard timer yes yes yes +zeros counters yes + + +sends flow_removed message --- --- --- % % + +(+) "modify" and "modify-strict" only take these actions when they + create a new flow, not when they update an existing flow. + +(%) "delete" and "delete_strict" generates a flow_removed message if + the deleted flow or flows have the OFPFF_SEND_FLOW_REM flag set. + (Each controller can separately control whether it wants to + receive the generated messages.) + + Multiple Table Support ======================