Commit graph

13 commits

Author SHA1 Message Date
Rusty Russell
679f46f733 common/amount: rename amount_sat_zero/amount_msat_zerp -> amount_sat_is_zero/amount_msat_is_zero.
I used `amount_msat_eq(x, AMOUNT_MSAT(0))` because I forgot this
function existed.  I probably missed it because the name is surprising,
so add "is" in there to make it clear it's a boolean function.

You'll note almost all the places which did use it are Eduardo's and
Lisa's code, so maybe it's just me.

Fix up a few places which I could use it, too.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2024-09-19 12:16:53 +09:30
Lagrang3
bb68e65b7a renepay: add precondition check + error msg
- add more checks
- add more error messages
- compute probabilities without fees during MCF
- compute probabilities with fees during get_routes

Signed-off-by: Lagrang3 <lagrang3@protonmail.com>
2024-08-19 10:11:35 -07:00
Lagrang3
7056018b15 renepay: add const probability cost
The probability for a success forward of x amount on a channel is now
computed as:

	P_success(x) = b * P_rene(x)

where P_rene(x) is the probability distribution proposed by Rene
Pickhardt with a uniform distribution on the known liquidity of the
channel and 'b' is a new parameter we add in this PR, by the name of
"base probability". The "base probability" represents the probability
for a channel in the network choosen at random to be able to forward at
least 1msat, ie. of being alive, non-depleted and with at least one HTLC
slot. We don't know the value of 'b', but for the moment we assume that
it is 0.98 and use that as default.

As a consequence the probability cost becomes non-linear and non-convex
because of the additional constant term:

	Cost(x) = - log P_success(x)
	        = - log b  -  - log P_rene(x)
		= - log b  +  Cost_rene(x)

We currently don't handle well base fees and neither this additional
"base probability" but we can as a first approximation linearize the
cost function in this way:

	Cost_linear(x) = (- log b)*x  +  Cost_rene_linear(x)

Changelog-Added: renepay: Add a dev parameter to renepay that represents
a constant probability of availability for all channels in the network.

Signed-off-by: Lagrang3 <lagrang3@protonmail.com>
2024-08-15 16:46:41 +09:30
Lagrang3
c0dd3cd826 renepay: disabled channels in a map
Expecting to have more than just a bunch of disabled channels if we
prune the lightning network heavily I am changing the internal data
structure of disabledmap from a simple array to a hashtable.

Have a finer control over disabled channels by targeting
short_channel_id_dir instead of short_channel_id,
ie. we can disable a single direction of a channel.

Signed-off-by: Lagrang3 <lagrang3@protonmail.com>
2024-08-12 22:44:58 -07:00
Lagrang3
c4d0447773 renepay: remove __PRETTY_FUNCTION__
Remove __PRETTY_FUNCTION__ in favor of __func__

Signed-off-by: Lagrang3 <lagrang3@protonmail.com>
2024-08-12 13:27:34 -07:00
Lagrang3
6a1776d312 renepay: rm HTLCs from uncertainty on route free
Add remove_htlc in the route destructor.

Signed-off-by: Lagrang3 <lagrang3@protonmail.com>
2024-08-12 13:27:34 -07:00
Rusty Russell
9b19eada30 common: promote useful routines from renepay.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2024-08-07 20:35:30 +09:30
Lagrang3
4adf9b4080 renepay: bug fix on the routebuilder
The route-builder checks the liquidity bounds of each route one at a
time. Every route that satisfy the contraints is recorded in the
uncertainty network and produces an HTLC burden on the channels it uses,
so that the following routes cannot count on the same liquidity twice.
2024-05-08 22:32:13 -05:00
Lagrang3
da00cae30b renepay: remove payment from route
Routes contain only routing information and the payment they're linked
to can be obtained through the payment_hash. We remove the dependency of
route building routines from the payment itself. In order to make
plain payment information available we define a payment_info structure.
2024-05-08 22:32:13 -05:00
Lagrang3
96bd0e455b renepay: refactor routefail
- use switch case over all possible WIRE_* errors,
- remove the virtual machine for routefail, use a simple two step
  solution: 1. update the gossip and 2. handle error cases
2024-05-08 22:32:13 -05:00
Lagrang3
cafc08be1d renepay: disable channels not in chan_extra_map
Expand the disabled set to include channels that are not present in the
chan_extra_map/uncertainty network.
2024-05-08 22:32:13 -05:00
Lagrang3
fa199e21d2 renepay: minor fixes 2024-05-08 22:32:13 -05:00
Lagrang3
84651fa4ba renepay: add routebuilder.c
Routebuilder constitute the module that builds the routes we try in the
payment. The public API is simply `get_routes`, it replaces the similar
interface for pay_flows.
2024-05-08 22:32:13 -05:00