Thanks you Joe the following citation is in a contradiction to the idea of pre-populating megaflows in kernel datapath . this is from http://docs.openvswitch.org/en/latest/faq/design/
"Q: Can OVS populate the kernel flow table in advance instead of in reaction to packets? A: No. There are several reasons: Kernel flows are not as sophisticated as OpenFlow flows, which means that some OpenFlow policies could require a large number of kernel flows. The “conjunctive match” feature is an extreme example: the number of kernel flows it requires is the product of the number of flows in each dimension. With multiple OpenFlow flow tables and simple sets of actions, the number of kernel flows required can be as large as the product of the number of flows in each dimension. With more sophisticated actions, the number of kernel flows could be even larger. Open vSwitch is designed so that any version of OVS userspace interoperates with any version of the OVS kernel module. This forward and backward compatibility requires that userspace observe how the kernel module parses received packets. This is only possible in a straightforward way when userspace adds kernel flows in reaction to received packets." Thanks in advance - Sara On Mon, Jul 24, 2017 at 10:58 PM, Joe Stringer <[email protected]> wrote: > On 23 July 2017 at 06:37, Sara Gittlin <[email protected]> wrote: >> Hello, >> I understand that there is a support for megaflows in the kernel and netlink. >> I also understand that there is no megaflow implementation in ofproto. >> i.e. there is no implementation of compressing (if possible) all flows >> in ofproto table to megaflows and installing it in the datapath. is >> that correct ? > > That's right - rather than pre-populating a representation of the > entire OpenFlow state, the ofproto-dpif implementation uses an > "upcall" model where the datapath acts as a cache for forwarding > behaviour, and the cache is populated on-demand as traffic arrives. _______________________________________________ discuss mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-discuss
