Thomas, > > Okay. How about: Push is simple and known to work; but it costs. > > Pull is harder, but may be cheaper. Still a very broad statement, > > but it allows the following question: > > I think it's not particularly useful to have a high-level discussion > about whether something as general as "push" vs. "pull" will work or > not. Push vs. pull are just two approaches. They both have plusses and > minuses. To decide which makes sense (and in what context), you have > to look at the overall problem, requirements, and a whole bunch of > factors. And different folk may weigh various factors differently. > > I'm not saying push can't work. In fact, I'm sure it can. But just > because it can work, doesn't mean other approaches should be ruled > out. > > > Is the savings (in whatever dimension) that Pull offers over Push > > worth the effort? > > I think so. At least, I don't want to see it ruled out up front. > > > >> I could ask you what happens to packets while the Pull is being > > >> responded to, or a bunch of related questions. I won't. > > > > > > They get queued. Or dropped. Or possibly something else. Yes, there > > > are implications to that. But not necessarily a show stopper either. > > > It was a show-stopper for Ipsilon. > > Now there is a soundbite. But I'm not sure exactly how that applies > here... > > > >>> In my view, this puts an unnecessary load on NVEs. > > > > > >> Let's talk instead about the "unnecessary load". Can someone quantify > > >> this? Is it CPU? memory? messaging? What's the bottleneck or pain > > >> point? > > > > > > Some or all of the above. > > > > > > If typical VNs are smallish, I agree that an NVE can preload full > > > tables with no problem. But what about for very large VNs? Should the > > > architecture *force* such preloading of full tables, even if the > > > working set of routes is actually very small? > > > I thought I picked a fairly large VN, with 10,000 members. Even if > > you take a larger one, say 100,000 members, the memory cost is (imo) > > small. > > It's not just memory, there is also the signalling cost. And if you > have 10K VMs, no doubt at any one time some (more?) are moving around, > with the corresponding signaling (using push), going out all the way > to *all* NVEs.
Perhaps you should learn how RT Constrain could be used to avoid sending the state for 10K VM "to *all* NVEs" Yakov. _______________________________________________ nvo3 mailing list [email protected] https://www.ietf.org/mailman/listinfo/nvo3
