Rename routing::router::test_utils to ::bench_utils
[rust-lightning] / lightning / src / routing / scoring.rs
index 95bb2559023daf474c7f462f0f15227dd4250a65..66900f2ba43bce7553bd951754c7684f3b314910 100644 (file)
@@ -102,6 +102,12 @@ pub trait Score $(: $supertrait)* {
 
        /// Handles updating channel penalties after successfully routing along a path.
        fn payment_path_successful(&mut self, path: &[&RouteHop]);
+
+       /// Handles updating channel penalties after a probe over the given path failed.
+       fn probe_failed(&mut self, path: &[&RouteHop], short_channel_id: u64);
+
+       /// Handles updating channel penalties after a probe over the given path succeeded.
+       fn probe_successful(&mut self, path: &[&RouteHop]);
 }
 
 impl<S: Score, T: DerefMut<Target=S> $(+ $supertrait)*> Score for T {
@@ -118,6 +124,14 @@ impl<S: Score, T: DerefMut<Target=S> $(+ $supertrait)*> Score for T {
        fn payment_path_successful(&mut self, path: &[&RouteHop]) {
                self.deref_mut().payment_path_successful(path)
        }
+
+       fn probe_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
+               self.deref_mut().probe_failed(path, short_channel_id)
+       }
+
+       fn probe_successful(&mut self, path: &[&RouteHop]) {
+               self.deref_mut().probe_successful(path)
+       }
 }
 } }
 
@@ -148,6 +162,7 @@ pub trait LockableScore<'a> {
 /// use the Persister to persist it.
 pub trait WriteableScore<'a>: LockableScore<'a> + Writeable {}
 
+#[cfg(not(c_bindings))]
 impl<'a, T> WriteableScore<'a> for T where T: LockableScore<'a> + Writeable {}
 
 /// (C-not exported)
@@ -173,12 +188,39 @@ pub struct MultiThreadedLockableScore<S: Score> {
        score: Mutex<S>,
 }
 #[cfg(c_bindings)]
-/// (C-not exported)
+/// A locked `MultiThreadedLockableScore`.
+pub struct MultiThreadedLockableScoreLock<'a, S: Score>(MutexGuard<'a, S>);
+#[cfg(c_bindings)]
+impl<'a, T: Score + 'a> Score for MultiThreadedLockableScoreLock<'a, T> {
+       fn channel_penalty_msat(&self, scid: u64, source: &NodeId, target: &NodeId, usage: ChannelUsage) -> u64 {
+               self.0.channel_penalty_msat(scid, source, target, usage)
+       }
+       fn payment_path_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
+               self.0.payment_path_failed(path, short_channel_id)
+       }
+       fn payment_path_successful(&mut self, path: &[&RouteHop]) {
+               self.0.payment_path_successful(path)
+       }
+       fn probe_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
+               self.0.probe_failed(path, short_channel_id)
+       }
+       fn probe_successful(&mut self, path: &[&RouteHop]) {
+               self.0.probe_successful(path)
+       }
+}
+#[cfg(c_bindings)]
+impl<'a, T: Score + 'a> Writeable for MultiThreadedLockableScoreLock<'a, T> {
+       fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
+               self.0.write(writer)
+       }
+}
+
+#[cfg(c_bindings)]
 impl<'a, T: Score + 'a> LockableScore<'a> for MultiThreadedLockableScore<T> {
-       type Locked = MutexGuard<'a, T>;
+       type Locked = MultiThreadedLockableScoreLock<'a, T>;
 
-       fn lock(&'a self) -> MutexGuard<'a, T> {
-               Mutex::lock(&self.score).unwrap()
+       fn lock(&'a self) -> MultiThreadedLockableScoreLock<'a, T> {
+               MultiThreadedLockableScoreLock(Mutex::lock(&self.score).unwrap())
        }
 }
 
@@ -207,7 +249,7 @@ impl<'a, S: Writeable> Writeable for MutexGuard<'a, S> {
 }
 
 /// Proposed use of a channel passed as a parameter to [`Score::channel_penalty_msat`].
-#[derive(Clone, Copy)]
+#[derive(Clone, Copy, Debug)]
 pub struct ChannelUsage {
        /// The amount to send through the channel, denominated in millisatoshis.
        pub amount_msat: u64,
@@ -241,6 +283,10 @@ impl Score for FixedPenaltyScorer {
        fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
 
        fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
+
+       fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
+
+       fn probe_successful(&mut self, _path: &[&RouteHop]) {}
 }
 
 impl Writeable for FixedPenaltyScorer {
@@ -306,6 +352,9 @@ where L::Target: Logger {
 ///
 /// Used to configure base, liquidity, and amount penalties, the sum of which comprises the channel
 /// penalty (i.e., the amount in msats willing to be paid to avoid routing through the channel).
+///
+/// The penalty applied to any channel by the [`ProbabilisticScorer`] is the sum of each of the
+/// parameters here.
 #[derive(Clone)]
 pub struct ProbabilisticScoringParameters {
        /// A fixed penalty in msats to apply to each channel.
@@ -313,6 +362,20 @@ pub struct ProbabilisticScoringParameters {
        /// Default value: 500 msat
        pub base_penalty_msat: u64,
 
+       /// A multiplier used with the payment amount to calculate a fixed penalty applied to each
+       /// channel, in excess of the [`base_penalty_msat`].
+       ///
+       /// The purpose of the amount penalty is to avoid having fees dominate the channel cost (i.e.,
+       /// fees plus penalty) for large payments. The penalty is computed as the product of this
+       /// multiplier and `2^30`ths of the payment amount.
+       ///
+       /// ie `base_penalty_amount_multiplier_msat * amount_msat / 2^30`
+       ///
+       /// Default value: 8,192 msat
+       ///
+       /// [`base_penalty_msat`]: Self::base_penalty_msat
+       pub base_penalty_amount_multiplier_msat: u64,
+
        /// A multiplier used in conjunction with the negative `log10` of the channel's success
        /// probability for a payment to determine the liquidity penalty.
        ///
@@ -351,7 +414,7 @@ pub struct ProbabilisticScoringParameters {
        /// multiplier and `2^20`ths of the payment amount, weighted by the negative `log10` of the
        /// success probability.
        ///
-       /// `-log10(success_probability) * amount_penalty_multiplier_msat * amount_msat / 2^20`
+       /// `-log10(success_probability) * liquidity_penalty_amount_multiplier_msat * amount_msat / 2^20`
        ///
        /// In practice, this means for 0.1 success probability (`-log10(0.1) == 1`) each `2^20`th of
        /// the amount will result in a penalty of the multiplier. And, as the success probability
@@ -360,12 +423,14 @@ pub struct ProbabilisticScoringParameters {
        /// fall below `1`.
        ///
        /// Default value: 256 msat
-       pub amount_penalty_multiplier_msat: u64,
+       pub liquidity_penalty_amount_multiplier_msat: u64,
 
-       /// A list of nodes that won't be considered during path finding.
+       /// Manual penalties used for the given nodes. Allows to set a particular penalty for a given
+       /// node. Note that a manual penalty of `u64::max_value()` means the node would not ever be
+       /// considered during path finding.
        ///
        /// (C-not exported)
-       pub banned_nodes: HashSet<NodeId>,
+       pub manual_node_penalties: HashMap<NodeId, u64>,
 
        /// This penalty is applied when `htlc_maximum_msat` is equal to or larger than half of the
        /// channel's capacity, which makes us prefer nodes with a smaller `htlc_maximum_msat`. We
@@ -374,6 +439,25 @@ pub struct ProbabilisticScoringParameters {
        ///
        /// Default value: 250 msat
        pub anti_probing_penalty_msat: u64,
+
+       /// This penalty is applied when the amount we're attempting to send over a channel exceeds our
+       /// current estimate of the channel's available liquidity.
+       ///
+       /// Note that in this case all other penalties, including the
+       /// [`liquidity_penalty_multiplier_msat`] and [`liquidity_penalty_amount_multiplier_msat`]-based
+       /// penalties, as well as the [`base_penalty_msat`] and the [`anti_probing_penalty_msat`], if
+       /// applicable, are still included in the overall penalty.
+       ///
+       /// If you wish to avoid creating paths with such channels entirely, setting this to a value of
+       /// `u64::max_value()` will guarantee that.
+       ///
+       /// Default value: 1_0000_0000_000 msat (1 Bitcoin)
+       ///
+       /// [`liquidity_penalty_multiplier_msat`]: Self::liquidity_penalty_multiplier_msat
+       /// [`liquidity_penalty_amount_multiplier_msat`]: Self::liquidity_penalty_amount_multiplier_msat
+       /// [`base_penalty_msat`]: Self::base_penalty_msat
+       /// [`anti_probing_penalty_msat`]: Self::anti_probing_penalty_msat
+       pub considered_impossible_penalty_msat: u64,
 }
 
 /// Accounting for channel liquidity balance uncertainty.
@@ -468,17 +552,27 @@ impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, T: Time> ProbabilisticScorerU
        /// Marks the node with the given `node_id` as banned, i.e.,
        /// it will be avoided during path finding.
        pub fn add_banned(&mut self, node_id: &NodeId) {
-               self.params.banned_nodes.insert(*node_id);
+               self.params.manual_node_penalties.insert(*node_id, u64::max_value());
        }
 
        /// Removes the node with the given `node_id` from the list of nodes to avoid.
        pub fn remove_banned(&mut self, node_id: &NodeId) {
-               self.params.banned_nodes.remove(node_id);
+               self.params.manual_node_penalties.remove(node_id);
+       }
+
+       /// Sets a manual penalty for the given node.
+       pub fn set_manual_penalty(&mut self, node_id: &NodeId, penalty: u64) {
+               self.params.manual_node_penalties.insert(*node_id, penalty);
+       }
+
+       /// Removes the node with the given `node_id` from the list of manual penalties.
+       pub fn remove_manual_penalty(&mut self, node_id: &NodeId) {
+               self.params.manual_node_penalties.remove(node_id);
        }
 
-       /// Clears the list of nodes that are avoided during path finding.
-       pub fn clear_banned(&mut self) {
-               self.params.banned_nodes = HashSet::new();
+       /// Clears the list of manual penalties that are applied during path finding.
+       pub fn clear_manual_penalties(&mut self) {
+               self.params.manual_node_penalties = HashMap::new();
        }
 }
 
@@ -487,11 +581,13 @@ impl ProbabilisticScoringParameters {
        fn zero_penalty() -> Self {
                Self {
                        base_penalty_msat: 0,
+                       base_penalty_amount_multiplier_msat: 0,
                        liquidity_penalty_multiplier_msat: 0,
                        liquidity_offset_half_life: Duration::from_secs(3600),
-                       amount_penalty_multiplier_msat: 0,
-                       banned_nodes: HashSet::new(),
+                       liquidity_penalty_amount_multiplier_msat: 0,
+                       manual_node_penalties: HashMap::new(),
                        anti_probing_penalty_msat: 0,
+                       considered_impossible_penalty_msat: 0,
                }
        }
 
@@ -499,7 +595,7 @@ impl ProbabilisticScoringParameters {
        /// they will be avoided during path finding.
        pub fn add_banned_from_list(&mut self, node_ids: Vec<NodeId>) {
                for id in node_ids {
-                       self.banned_nodes.insert(id);
+                       self.manual_node_penalties.insert(id, u64::max_value());
                }
        }
 }
@@ -508,11 +604,13 @@ impl Default for ProbabilisticScoringParameters {
        fn default() -> Self {
                Self {
                        base_penalty_msat: 500,
+                       base_penalty_amount_multiplier_msat: 8192,
                        liquidity_penalty_multiplier_msat: 40_000,
                        liquidity_offset_half_life: Duration::from_secs(3600),
-                       amount_penalty_multiplier_msat: 256,
-                       banned_nodes: HashSet::new(),
+                       liquidity_penalty_amount_multiplier_msat: 256,
+                       manual_node_penalties: HashMap::new(),
                        anti_probing_penalty_msat: 250,
+                       considered_impossible_penalty_msat: 1_0000_0000_000,
                }
        }
 }
@@ -580,35 +678,31 @@ const PRECISION_LOWER_BOUND_DENOMINATOR: u64 = approx::LOWER_BITS_BOUND;
 
 /// The divisor used when computing the amount penalty.
 const AMOUNT_PENALTY_DIVISOR: u64 = 1 << 20;
+const BASE_AMOUNT_PENALTY_DIVISOR: u64 = 1 << 30;
 
 impl<L: Deref<Target = u64>, T: Time, U: Deref<Target = T>> DirectedChannelLiquidity<L, T, U> {
-       /// Returns a penalty for routing the given HTLC `amount_msat` through the channel in this
-       /// direction.
+       /// Returns a liquidity penalty for routing the given HTLC `amount_msat` through the channel in
+       /// this direction.
        fn penalty_msat(&self, amount_msat: u64, params: &ProbabilisticScoringParameters) -> u64 {
                let max_liquidity_msat = self.max_liquidity_msat();
                let min_liquidity_msat = core::cmp::min(self.min_liquidity_msat(), max_liquidity_msat);
                if amount_msat <= min_liquidity_msat {
                        0
                } else if amount_msat >= max_liquidity_msat {
-                       if amount_msat > max_liquidity_msat {
-                               u64::max_value()
-                       } else if max_liquidity_msat != self.capacity_msat {
-                               // Avoid using the failed channel on retry.
-                               u64::max_value()
-                       } else {
-                               // Equivalent to hitting the else clause below with the amount equal to the
-                               // effective capacity and without any certainty on the liquidity upper bound.
-                               let negative_log10_times_2048 = NEGATIVE_LOG10_UPPER_BOUND * 2048;
-                               self.combined_penalty_msat(amount_msat, negative_log10_times_2048, params)
-                       }
+                       // Equivalent to hitting the else clause below with the amount equal to the effective
+                       // capacity and without any certainty on the liquidity upper bound, plus the
+                       // impossibility penalty.
+                       let negative_log10_times_2048 = NEGATIVE_LOG10_UPPER_BOUND * 2048;
+                       self.combined_penalty_msat(amount_msat, negative_log10_times_2048, params)
+                               .saturating_add(params.considered_impossible_penalty_msat)
                } else {
                        let numerator = (max_liquidity_msat - amount_msat).saturating_add(1);
                        let denominator = (max_liquidity_msat - min_liquidity_msat).saturating_add(1);
                        if amount_msat - min_liquidity_msat < denominator / PRECISION_LOWER_BOUND_DENOMINATOR {
                                // If the failure probability is < 1.5625% (as 1 - numerator/denominator < 1/64),
                                // don't bother trying to use the log approximation as it gets too noisy to be
-                               // particularly helpful, instead just round down to 0 and return the base penalty.
-                               params.base_penalty_msat
+                               // particularly helpful, instead just round down to 0.
+                               0
                        } else {
                                let negative_log10_times_2048 =
                                        approx::negative_log10_times_2048(numerator, denominator);
@@ -617,7 +711,7 @@ impl<L: Deref<Target = u64>, T: Time, U: Deref<Target = T>> DirectedChannelLiqui
                }
        }
 
-       /// Computes the liquidity and amount penalties and adds them to the base penalty.
+       /// Computes the liquidity penalty from the penalty multipliers.
        #[inline(always)]
        fn combined_penalty_msat(
                &self, amount_msat: u64, negative_log10_times_2048: u64,
@@ -630,12 +724,10 @@ impl<L: Deref<Target = u64>, T: Time, U: Deref<Target = T>> DirectedChannelLiqui
                        (negative_log10_times_2048.saturating_mul(multiplier_msat) / 2048).min(max_penalty_msat)
                };
                let amount_penalty_msat = negative_log10_times_2048
-                       .saturating_mul(params.amount_penalty_multiplier_msat)
+                       .saturating_mul(params.liquidity_penalty_amount_multiplier_msat)
                        .saturating_mul(amount_msat) / 2048 / AMOUNT_PENALTY_DIVISOR;
 
-               params.base_penalty_msat
-                       .saturating_add(liquidity_penalty_msat)
-                       .saturating_add(amount_penalty_msat)
+               liquidity_penalty_msat.saturating_add(amount_penalty_msat)
        }
 
        /// Returns the lower bound of the channel liquidity balance in this direction.
@@ -713,17 +805,21 @@ impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, T: Time> Score for Probabilis
        fn channel_penalty_msat(
                &self, short_channel_id: u64, source: &NodeId, target: &NodeId, usage: ChannelUsage
        ) -> u64 {
-               if self.params.banned_nodes.contains(source) || self.params.banned_nodes.contains(target) {
-                       return u64::max_value();
+               if let Some(penalty) = self.params.manual_node_penalties.get(target) {
+                       return *penalty;
                }
 
+               let base_penalty_msat = self.params.base_penalty_msat.saturating_add(
+                       self.params.base_penalty_amount_multiplier_msat
+                               .saturating_mul(usage.amount_msat) / BASE_AMOUNT_PENALTY_DIVISOR);
+
                let mut anti_probing_penalty_msat = 0;
                match usage.effective_capacity {
                        EffectiveCapacity::ExactLiquidity { liquidity_msat } => {
                                if usage.amount_msat > liquidity_msat {
                                        return u64::max_value();
                                } else {
-                                       return self.params.base_penalty_msat;
+                                       return base_penalty_msat;
                                }
                        },
                        EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat: Some(htlc_maximum_msat) } => {
@@ -744,6 +840,7 @@ impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, T: Time> Score for Probabilis
                        .as_directed(source, target, capacity_msat, liquidity_offset_half_life)
                        .penalty_msat(amount_msat, &self.params)
                        .saturating_add(anti_probing_penalty_msat)
+                       .saturating_add(base_penalty_msat)
        }
 
        fn payment_path_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
@@ -811,6 +908,14 @@ impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, T: Time> Score for Probabilis
                        }
                }
        }
+
+       fn probe_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
+               self.payment_path_failed(path, short_channel_id)
+       }
+
+       fn probe_successful(&mut self, path: &[&RouteHop]) {
+               self.payment_path_failed(path, u64::max_value())
+       }
 }
 
 mod approx {
@@ -1203,8 +1308,8 @@ mod tests {
        use util::time::Time;
        use util::time::tests::SinceEpoch;
 
-       use ln::features::{ChannelFeatures, NodeFeatures};
-       use ln::msgs::{ChannelAnnouncement, ChannelUpdate, OptionalField, UnsignedChannelAnnouncement, UnsignedChannelUpdate};
+       use ln::channelmanager;
+       use ln::msgs::{ChannelAnnouncement, ChannelUpdate, UnsignedChannelAnnouncement, UnsignedChannelUpdate};
        use routing::gossip::{EffectiveCapacity, NetworkGraph, NodeId};
        use routing::router::RouteHop;
        use routing::scoring::{ChannelUsage, Score};
@@ -1294,7 +1399,7 @@ mod tests {
                let node_2_secret = &SecretKey::from_slice(&[40; 32]).unwrap();
                let secp_ctx = Secp256k1::new();
                let unsigned_announcement = UnsignedChannelAnnouncement {
-                       features: ChannelFeatures::known(),
+                       features: channelmanager::provided_channel_features(),
                        chain_hash: genesis_hash,
                        short_channel_id,
                        node_id_1: PublicKey::from_secret_key(&secp_ctx, &node_1_key),
@@ -1331,7 +1436,7 @@ mod tests {
                        flags,
                        cltv_expiry_delta: 18,
                        htlc_minimum_msat: 0,
-                       htlc_maximum_msat: OptionalField::Present(1_000),
+                       htlc_maximum_msat: 1_000,
                        fee_base_msat: 1,
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new(),
@@ -1348,25 +1453,25 @@ mod tests {
                vec![
                        RouteHop {
                                pubkey: source_pubkey(),
-                               node_features: NodeFeatures::known(),
+                               node_features: channelmanager::provided_node_features(),
                                short_channel_id: 41,
-                               channel_features: ChannelFeatures::known(),
+                               channel_features: channelmanager::provided_channel_features(),
                                fee_msat: 1,
                                cltv_expiry_delta: 18,
                        },
                        RouteHop {
                                pubkey: target_pubkey(),
-                               node_features: NodeFeatures::known(),
+                               node_features: channelmanager::provided_node_features(),
                                short_channel_id: 42,
-                               channel_features: ChannelFeatures::known(),
+                               channel_features: channelmanager::provided_channel_features(),
                                fee_msat: 2,
                                cltv_expiry_delta: 18,
                        },
                        RouteHop {
                                pubkey: recipient_pubkey(),
-                               node_features: NodeFeatures::known(),
+                               node_features: channelmanager::provided_node_features(),
                                short_channel_id: 43,
-                               channel_features: ChannelFeatures::known(),
+                               channel_features: channelmanager::provided_channel_features(),
                                fee_msat: amount_msat,
                                cltv_expiry_delta: 18,
                        },
@@ -1586,7 +1691,7 @@ mod tests {
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 0);
                let usage = ChannelUsage { amount_msat: 102_400, ..usage };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 47);
-               let usage = ChannelUsage { amount_msat: 1_024_000, ..usage };
+               let usage = ChannelUsage { amount_msat: 1_023_999, ..usage };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2_000);
 
                let usage = ChannelUsage {
@@ -1616,6 +1721,7 @@ mod tests {
                let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
+                       considered_impossible_penalty_msat: u64::max_value(),
                        ..ProbabilisticScoringParameters::zero_penalty()
                };
                let scorer = ProbabilisticScorer::new(params, &network_graph, &logger)
@@ -1707,6 +1813,7 @@ mod tests {
                let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
+                       considered_impossible_penalty_msat: u64::max_value(),
                        ..ProbabilisticScoringParameters::zero_penalty()
                };
                let mut scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
@@ -1773,6 +1880,7 @@ mod tests {
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
                        liquidity_offset_half_life: Duration::from_secs(10),
+                       considered_impossible_penalty_msat: u64::max_value(),
                        ..ProbabilisticScoringParameters::zero_penalty()
                };
                let mut scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
@@ -1782,10 +1890,10 @@ mod tests {
                let usage = ChannelUsage {
                        amount_msat: 0,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024, htlc_maximum_msat: Some(1_000) },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024, htlc_maximum_msat: Some(1_024) },
                };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 0);
-               let usage = ChannelUsage { amount_msat: 1_024, ..usage };
+               let usage = ChannelUsage { amount_msat: 1_023, ..usage };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2_000);
 
                scorer.payment_path_failed(&payment_path_for_amount(768).iter().collect::<Vec<_>>(), 42);
@@ -1829,20 +1937,20 @@ mod tests {
                let usage = ChannelUsage { amount_msat: 1_023, ..usage };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2_000);
                let usage = ChannelUsage { amount_msat: 1_024, ..usage };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2_000);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), u64::max_value());
 
                // Fully decay liquidity upper bound.
                SinceEpoch::advance(Duration::from_secs(10));
                let usage = ChannelUsage { amount_msat: 0, ..usage };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 0);
                let usage = ChannelUsage { amount_msat: 1_024, ..usage };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2_000);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), u64::max_value());
 
                SinceEpoch::advance(Duration::from_secs(10));
                let usage = ChannelUsage { amount_msat: 0, ..usage };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 0);
                let usage = ChannelUsage { amount_msat: 1_024, ..usage };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2_000);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), u64::max_value());
        }
 
        #[test]
@@ -1927,6 +2035,7 @@ mod tests {
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
                        liquidity_offset_half_life: Duration::from_secs(10),
+                       considered_impossible_penalty_msat: u64::max_value(),
                        ..ProbabilisticScoringParameters::zero_penalty()
                };
                let mut scorer = ProbabilisticScorer::new(params.clone(), &network_graph, &logger);
@@ -1963,6 +2072,7 @@ mod tests {
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
                        liquidity_offset_half_life: Duration::from_secs(10),
+                       considered_impossible_penalty_msat: u64::max_value(),
                        ..ProbabilisticScoringParameters::zero_penalty()
                };
                let mut scorer = ProbabilisticScorer::new(params.clone(), &network_graph, &logger);
@@ -2010,47 +2120,47 @@ mod tests {
                        inflight_htlc_msat: 0,
                        effective_capacity: EffectiveCapacity::Total { capacity_msat: 950_000_000, htlc_maximum_msat: Some(1_000) },
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 3613);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 4375);
                let usage = ChannelUsage {
                        effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1977);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2739);
                let usage = ChannelUsage {
                        effective_capacity: EffectiveCapacity::Total { capacity_msat: 2_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1474);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2236);
                let usage = ChannelUsage {
                        effective_capacity: EffectiveCapacity::Total { capacity_msat: 3_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1223);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1985);
                let usage = ChannelUsage {
                        effective_capacity: EffectiveCapacity::Total { capacity_msat: 4_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 877);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1639);
                let usage = ChannelUsage {
                        effective_capacity: EffectiveCapacity::Total { capacity_msat: 5_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 845);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1607);
                let usage = ChannelUsage {
                        effective_capacity: EffectiveCapacity::Total { capacity_msat: 6_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 500);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1262);
                let usage = ChannelUsage {
                        effective_capacity: EffectiveCapacity::Total { capacity_msat: 7_450_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 500);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1262);
                let usage = ChannelUsage {
                        effective_capacity: EffectiveCapacity::Total { capacity_msat: 7_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 500);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1262);
                let usage = ChannelUsage {
                        effective_capacity: EffectiveCapacity::Total { capacity_msat: 8_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 500);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1262);
                let usage = ChannelUsage {
                        effective_capacity: EffectiveCapacity::Total { capacity_msat: 9_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 500);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1262);
        }
 
        #[test]
@@ -2078,6 +2188,15 @@ mod tests {
                };
                let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 558);
+
+               let params = ProbabilisticScoringParameters {
+                       base_penalty_msat: 500, liquidity_penalty_multiplier_msat: 1_000,
+                       base_penalty_amount_multiplier_msat: (1 << 30),
+                       anti_probing_penalty_msat: 0, ..Default::default()
+               };
+
+               let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 558 + 128);
        }
 
        #[test]
@@ -2094,7 +2213,7 @@ mod tests {
 
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
-                       amount_penalty_multiplier_msat: 0,
+                       liquidity_penalty_amount_multiplier_msat: 0,
                        ..ProbabilisticScoringParameters::zero_penalty()
                };
                let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
@@ -2102,7 +2221,7 @@ mod tests {
 
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
-                       amount_penalty_multiplier_msat: 256,
+                       liquidity_penalty_amount_multiplier_msat: 256,
                        ..ProbabilisticScoringParameters::zero_penalty()
                };
                let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
@@ -2133,7 +2252,10 @@ mod tests {
        fn accounts_for_inflight_htlc_usage() {
                let logger = TestLogger::new();
                let network_graph = network_graph(&logger);
-               let params = ProbabilisticScoringParameters::default();
+               let params = ProbabilisticScoringParameters {
+                       considered_impossible_penalty_msat: u64::max_value(),
+                       ..ProbabilisticScoringParameters::zero_penalty()
+               };
                let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
                let source = source_node_id();
                let target = target_node_id();