From r.pickhardt at googlemail.com Fri Mar 29 09:18:11 2019 From: r.pickhardt at googlemail.com (=?UTF-8?Q?Ren=C3=A9_Pickhardt?=) Date: Fri, 29 Mar 2019 10:18:11 +0100 Subject: [Lightning-dev] Routemap scaling (was: Just in Time Routing (JIT-Routing) and a channel rebalancing heuristic as an add on for improved routing success in BOLT 1.0) In-Reply-To: References: Message-ID: Good morning ZmnSCPxj, Maybe I oversee something - in that case sorry for spamming the list - but I don't understand how you could know the distance from yourself if you don't know the entire topology? (unless u use it on the pruned view as you suggested) On the other hand querying for a certain depth would be possible with the suggested `query ask egonetwork` in case for depth 3 one would have to peer with the nodes from the friend of a friend network. Best Rene ZmnSCPxj schrieb am Fr., 29. M?rz 2019, 09:47: > Good morning Rene, > > > Sent with ProtonMail Secure Email. > > ??????? Original Message ??????? > On Friday, March 29, 2019 1:54 PM, Ren? Pickhardt < > r.pickhardt at googlemail.com> wrote: > > > Dear ZmnSCPxj and fellow lightning developers, > > > > I want to point out two things and make a suggestion for a new gossip > message. > > > > > A good pruning heuristic is "channel capacity", which can be checked > onchain (the value of the UTXO backing the channel is the channel capacity). > > > It is good to keep channels with large capacity in the routemap, > because such large channels are more likely to successfully route a payment > than smaller channels. > > > So it is reasonable to delete channels with low capacity when the > routemap memory is becoming close to full. > > > > Intuitively (without simulation). I encourage to make that process not > deerministic but rather probabilistic. It would be good if everyone had a > different set of channels. (which is somewhat achieved with everyone > keeping their local view) > > At a software engineer point-of-view, probabilistic can be difficult to > test. > This can be made deterministic by including an RNG seed in the input to > this code. > > However, let me propose instead, in combination with your later thought: > > > > > > Nodes still need to track their direct channels (so they are > implicitly always in the routemap). > > > > I strongly advice that the local view should be extended. Every node > should always track their friends of a friend network. > > Perhaps the pruning rule can be modified to include *distance from self* > in addition to channel capacity. > The nearer the channel is, the more likely it is retained. > The further, the less likely. > The larger the channel is, the more likely it is retained. > The smaller, the less likely. > > The capacity divided by the distance can be used as a sorting key, and if > pruning is needed, the smallest "score" is pruned until the routemap fits. > > This will lead to everyone having a different set of channels, while being > likely to track their friend-of-friend network compared to more distant > nodes. > > Of course, the pruning itself would affect the distance of the channel to > the "self" node. > So determinism may be difficult to achieve here anyway. > > Regards, > ZmnSCPxj > -------------- next part -------------- An HTML attachment was scrubbed... URL: