The idea is to write ovn-northd in nlog program. In order to do that, we need a hook to ovs-db, which is the next step I am going to do. Generally, a subset of ovs-db tables will be input tables to the nlog engine and the engine's output table will also be written to ovs-db.
If we think about ovn-northd as a data converter (function) between north bound tables and south bound tables, it is straightforward that any engine that works in this way could be used. The improvement comes from incremental computation. As for the scalability, the paper [2] may not apply to OVN since they are of totally different design. In order to test the engine, we could try the interactive test case. There is one combo test case in the patch and it has an interactive mode. We could load a nlog program and run data on it. -- Yusheng ________________________________________ From: Hui Kang <ka...@us.ibm.com> Sent: Friday, June 17, 2016 3:28 PM To: Yusheng Wang Cc: dev@openvswitch.org Subject: Re: [ovs-dev] [PATCH] OVN: initial patch of datalog engine Hi, Yusheng, I am very intersted in testing your nice nlog implementation. Meanwhile, I appreciate if you could look at some questions I have about this nlog. - Reading the early proposal of nlog [1], I understand that nlog will be serving as a new computation model for ovn-northd. Furthermore, I think the plan is to replace the existing join_XXX operations (e.g., [3][4]) in populating tables in southbound database. Is my understanding correct? - How much performance improvement will you expect from using nlog? The NVP paper [2] mentioned in section 8.2 that even with nlog, the scalability issue still exists because Openflow in hypervisors requires O(N^2). Thanks in advance. - Hui _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
