Commit Graph

13 Commits

Author SHA1 Message Date
Joost Jager
3aaf32dc2e
routing: improve equal cost route comparison
When the (virtual) payment attempt cost is set to zero, probabilities
are no longer a factor in determining the best route. In case of routes
with equal costs, we'd just go with the first one found. This commit
refines this behavior by picking the route with the highest probability.
So even though probability doesn't affect the route cost, it is still
used as a tie breaker.
2019-12-02 14:23:57 +01:00
Juan Pablo Civile
df70095ad0 routing: optimize path finding structures
distance map now holds the edge the current path is coming from,
removing the need for next map.

Both distance map and distanceHeap now hold pointers instead of the full
struct to reduce allocations and copies.

Both these changes reduced path finding time by ~5% and memory usage by
~2mb.
2019-10-24 21:38:07 -03:00
Juan Pablo Civile
3e60a23632 routing: pre-allocate the distance map to an estimated node count
Pre-sizing these structures avoids a lot of map resizing, which causes
copies and rehashing of entries. We mostly know that the map won't
exceed that size, and it doesn't affect memory usage in any significant
way.
2019-10-24 21:31:30 -03:00
Joost Jager
3d7de2ad39
multi: remove dead code 2019-09-10 17:21:59 +02:00
nsa
7e6a34532e routing: add index map to distanceHeap
This commit adds the pubkeyIndices map to the distanceHeap to avoid
duplicate entries on the heap. This happened in the earlier iteration
of the findPath algorithm and would cause the driving loop to
evaluate already evaluated entries when there was no need.
2019-07-12 06:08:01 -04:00
nsa
61a1ab08fb routing+channeldb: findPath uses Vertex instead of LightningNode
This commit modifies the nodeWithDist struct to use a route.Vertex
instead of a *channeldb.LightningNode. This change, coupled with
the new ForEachNodeChannel function, allows the findPath Djikstra's
algorithm to cut down on database lookups since we no longer need
to call the FetchOtherNode function.
2019-07-12 06:08:01 -04:00
Joost Jager
6b70791c2d
routing: use probability source in path finding
This PR replaces the previously used edge and node ignore lists in path
finding by a probability based system. It modifies path finding so that
it not only compares routes on fee and time lock, but also takes route
success probability into account.

Allowing routes to be compared based on success probability is achieved
by introducing a 'virtual' cost of a payment attempt and using that to
translate probability into another cost factor.
2019-06-04 10:00:21 +02:00
Joost Jager
6006549ed5
routing: enforce cltv limit in path finding 2019-03-19 10:36:45 +01:00
Joost Jager
a779004a18
lnrpc+routing: fix issues with missing data in unmarshallRoute
In this commit the dependency of unmarshallRoute on edge policies being
available is removed. Edge policies may be unknown and reported as nil.
SendToRoute does not need the policies, but it does need pubkeys of the
route hops. In this commit, unmarshallRoute is modified so that it
takes the pubkeys from edgeInfo instead of channelEdgePolicy.

In addition to this, the route structure is simplified. No more connection
to the database at that point. Fees are determined based on incoming and
outgoing amounts.
2018-10-13 22:59:23 +02:00
Joost Jager
3e7473f4f0 routing: backward searching 2018-08-09 20:23:40 -07:00
Olaoluwa Osuntokun
528aa67df7
routing: weight findPath more heavily towards fees during edge relaxation
In this commit, we modify the edgeWeight function that’s used within
the findPath method to weight fees more heavily than the time lock
value at an edge. We do this in order to greedily prefer lower fees
during path finding. This is a simple stop gap in place of more complex
weighting parameters that will be investigated later.

We also modify the edge distance to use an int64 rather than a float.
Finally an additional test has been added in order to excessive this
new change. Before the commit, the test was failing as we preferred the
route with lower total time lock.
2018-02-12 16:27:38 -08:00
Olaoluwa Osuntokun
9f96ceb1e0
routing: introduce new heap for storing candidate shortest paths
This commit adds a new heap structure to heap.go which will be used for
storing candidate paths during the iterations of the k-shortest paths
algorithm.
2017-03-21 12:20:30 -07:00
Olaoluwa Osuntokun
606b23df43
routing: introduce a heap to keep track of closest nodes during pathfinding
This commit introduces a new heap struct that will be used to keep
track of the next closest node to the source during path finding within
our modified Dijkstra's algorithm.
2017-03-21 12:20:18 -07:00