Merge pull request #1524 from ViktorTigerstrom/2022-06-update-fail-holding-cell-htlcs...
[rust-lightning] / lightning / src / routing / router.rs
index 8731e66da9bd866bd82d00bc42c8922cd25508e8..90e658604ad1058040643e5b6be48fd93cfe29a8 100644 (file)
@@ -9,7 +9,7 @@
 
 //! The top-level routing/network map tracking logic lives here.
 //!
-//! You probably want to create a NetGraphMsgHandler and use that as your RoutingMessageHandler and then
+//! You probably want to create a P2PGossipSync and use that as your RoutingMessageHandler and then
 //! interrogate it to get routes for your own payments.
 
 use bitcoin::secp256k1::PublicKey;
@@ -17,8 +17,8 @@ use bitcoin::secp256k1::PublicKey;
 use ln::channelmanager::ChannelDetails;
 use ln::features::{ChannelFeatures, InvoiceFeatures, NodeFeatures};
 use ln::msgs::{DecodeError, ErrorAction, LightningError, MAX_VALUE_MSAT};
+use routing::gossip::{DirectedChannelInfoWithUpdate, EffectiveCapacity, ReadOnlyNetworkGraph, NodeId, RoutingFees};
 use routing::scoring::{ChannelUsage, Score};
-use routing::network_graph::{DirectedChannelInfoWithUpdate, EffectiveCapacity, NetworkGraph, ReadOnlyNetworkGraph, NodeId, RoutingFees};
 use util::ser::{Writeable, Readable, Writer};
 use util::logger::{Level, Logger};
 use util::chacha20::ChaCha20;
@@ -369,7 +369,7 @@ enum CandidateRouteHop<'a> {
        FirstHop {
                details: &'a ChannelDetails,
        },
-       /// A hop found in the [`NetworkGraph`], where the channel capacity may or may not be known.
+       /// A hop found in the [`ReadOnlyNetworkGraph`], where the channel capacity may be unknown.
        PublicHop {
                info: DirectedChannelInfoWithUpdate<'a>,
                short_channel_id: u64,
@@ -650,8 +650,8 @@ fn default_node_features() -> NodeFeatures {
 /// Private routing paths between a public node and the target may be included in `params.payee`.
 ///
 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
-/// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of our local
-/// channels from [`NetworkGraph`] will be ignored, and only those in `first_hops` will be used.
+/// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
+/// from `network_graph` will be ignored, and only those in `first_hops` will be used.
 ///
 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
@@ -670,16 +670,17 @@ fn default_node_features() -> NodeFeatures {
 ///
 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
+/// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
 pub fn find_route<L: Deref, S: Score>(
-       our_node_pubkey: &PublicKey, route_params: &RouteParameters, network: &NetworkGraph,
-       first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S, random_seed_bytes: &[u8; 32]
+       our_node_pubkey: &PublicKey, route_params: &RouteParameters,
+       network_graph: &ReadOnlyNetworkGraph, first_hops: Option<&[&ChannelDetails]>, logger: L,
+       scorer: &S, random_seed_bytes: &[u8; 32]
 ) -> Result<Route, LightningError>
 where L::Target: Logger {
-       let network_graph = network.read_only();
-       let mut route = get_route(our_node_pubkey, &route_params.payment_params, &network_graph, first_hops,
+       let mut route = get_route(our_node_pubkey, &route_params.payment_params, network_graph, first_hops,
                route_params.final_value_msat, route_params.final_cltv_expiry_delta, logger, scorer,
                random_seed_bytes)?;
-       add_random_cltv_offset(&mut route, &route_params.payment_params, &network_graph, random_seed_bytes);
+       add_random_cltv_offset(&mut route, &route_params.payment_params, network_graph, random_seed_bytes);
        Ok(route)
 }
 
@@ -1787,11 +1788,10 @@ fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
 ///
 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
 pub fn build_route_from_hops<L: Deref>(
-       our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters, network: &NetworkGraph,
-       logger: L, random_seed_bytes: &[u8; 32]
+       our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
+       network_graph: &ReadOnlyNetworkGraph, logger: L, random_seed_bytes: &[u8; 32]
 ) -> Result<Route, LightningError>
 where L::Target: Logger {
-       let network_graph = network.read_only();
        let mut route = build_route_from_hops_internal(
                our_node_pubkey, hops, &route_params.payment_params, &network_graph,
                route_params.final_value_msat, route_params.final_cltv_expiry_delta, logger, random_seed_bytes)?;
@@ -1858,7 +1858,7 @@ fn build_route_from_hops_internal<L: Deref>(
 
 #[cfg(test)]
 mod tests {
-       use routing::network_graph::{NetworkGraph, NetGraphMsgHandler, NodeId};
+       use routing::gossip::{NetworkGraph, P2PGossipSync, NodeId};
        use routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
                PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
                DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE};
@@ -1926,7 +1926,7 @@ mod tests {
 
        // Using the same keys for LN and BTC ids
        fn add_channel(
-               net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
+               gossip_sync: &P2PGossipSync<Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
                secp_ctx: &Secp256k1<All>, node_1_privkey: &SecretKey, node_2_privkey: &SecretKey, features: ChannelFeatures, short_channel_id: u64
        ) {
                let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
@@ -1951,14 +1951,14 @@ mod tests {
                        bitcoin_signature_2: secp_ctx.sign_ecdsa(&msghash, node_2_privkey),
                        contents: unsigned_announcement.clone(),
                };
-               match net_graph_msg_handler.handle_channel_announcement(&valid_announcement) {
+               match gossip_sync.handle_channel_announcement(&valid_announcement) {
                        Ok(res) => assert!(res),
                        _ => panic!()
                };
        }
 
        fn update_channel(
-               net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
+               gossip_sync: &P2PGossipSync<Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
                secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, update: UnsignedChannelUpdate
        ) {
                let msghash = hash_to_message!(&Sha256dHash::hash(&update.encode()[..])[..]);
@@ -1967,14 +1967,14 @@ mod tests {
                        contents: update.clone()
                };
 
-               match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
+               match gossip_sync.handle_channel_update(&valid_channel_update) {
                        Ok(res) => assert!(res),
                        Err(_) => panic!()
                };
        }
 
        fn add_or_update_node(
-               net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
+               gossip_sync: &P2PGossipSync<Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
                secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, features: NodeFeatures, timestamp: u32
        ) {
                let node_id = PublicKey::from_secret_key(&secp_ctx, node_privkey);
@@ -1994,7 +1994,7 @@ mod tests {
                        contents: unsigned_announcement.clone()
                };
 
-               match net_graph_msg_handler.handle_node_announcement(&valid_announcement) {
+               match gossip_sync.handle_node_announcement(&valid_announcement) {
                        Ok(_) => (),
                        Err(_) => panic!()
                };
@@ -2029,15 +2029,16 @@ mod tests {
        }
 
        fn build_line_graph() -> (
-               Secp256k1<All>, sync::Arc<NetworkGraph>, NetGraphMsgHandler<sync::Arc<NetworkGraph>,
-               sync::Arc<test_utils::TestChainSource>, sync::Arc<crate::util::test_utils::TestLogger>>,
+               Secp256k1<All>, sync::Arc<NetworkGraph<Arc<test_utils::TestLogger>>>,
+               P2PGossipSync<sync::Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, sync::Arc<test_utils::TestChainSource>, sync::Arc<test_utils::TestLogger>>,
                sync::Arc<test_utils::TestChainSource>, sync::Arc<test_utils::TestLogger>,
        ) {
                let secp_ctx = Secp256k1::new();
                let logger = Arc::new(test_utils::TestLogger::new());
                let chain_monitor = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
-               let network_graph = Arc::new(NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()));
-               let net_graph_msg_handler = NetGraphMsgHandler::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
+               let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
+               let network_graph = Arc::new(NetworkGraph::new(genesis_hash, Arc::clone(&logger)));
+               let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
 
                // Build network from our_id to node 19:
                // our_id -1(1)2- node0 -1(2)2- node1 - ... - node19
@@ -2046,9 +2047,9 @@ mod tests {
                for (idx, (cur_privkey, next_privkey)) in core::iter::once(&our_privkey)
                        .chain(privkeys.iter()).zip(privkeys.iter()).enumerate() {
                        let cur_short_channel_id = (idx as u64) + 1;
-                       add_channel(&net_graph_msg_handler, &secp_ctx, &cur_privkey, &next_privkey,
+                       add_channel(&gossip_sync, &secp_ctx, &cur_privkey, &next_privkey,
                                ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), cur_short_channel_id);
-                       update_channel(&net_graph_msg_handler, &secp_ctx, &cur_privkey, UnsignedChannelUpdate {
+                       update_channel(&gossip_sync, &secp_ctx, &cur_privkey, UnsignedChannelUpdate {
                                chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                                short_channel_id: cur_short_channel_id,
                                timestamp: idx as u32,
@@ -2060,7 +2061,7 @@ mod tests {
                                fee_proportional_millionths: 0,
                                excess_data: Vec::new()
                        });
-                       update_channel(&net_graph_msg_handler, &secp_ctx, &next_privkey, UnsignedChannelUpdate {
+                       update_channel(&gossip_sync, &secp_ctx, &next_privkey, UnsignedChannelUpdate {
                                chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                                short_channel_id: cur_short_channel_id,
                                timestamp: (idx as u32)+1,
@@ -2072,25 +2073,26 @@ mod tests {
                                fee_proportional_millionths: 0,
                                excess_data: Vec::new()
                        });
-                       add_or_update_node(&net_graph_msg_handler, &secp_ctx, next_privkey,
+                       add_or_update_node(&gossip_sync, &secp_ctx, next_privkey,
                                NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
                }
 
-               (secp_ctx, network_graph, net_graph_msg_handler, chain_monitor, logger)
+               (secp_ctx, network_graph, gossip_sync, chain_monitor, logger)
        }
 
        fn build_graph() -> (
                Secp256k1<All>,
-               sync::Arc<NetworkGraph>,
-               NetGraphMsgHandler<sync::Arc<NetworkGraph>, sync::Arc<test_utils::TestChainSource>, sync::Arc<crate::util::test_utils::TestLogger>>,
+               sync::Arc<NetworkGraph<Arc<test_utils::TestLogger>>>,
+               P2PGossipSync<sync::Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, sync::Arc<test_utils::TestChainSource>, sync::Arc<test_utils::TestLogger>>,
                sync::Arc<test_utils::TestChainSource>,
                sync::Arc<test_utils::TestLogger>,
        ) {
                let secp_ctx = Secp256k1::new();
                let logger = Arc::new(test_utils::TestLogger::new());
                let chain_monitor = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
-               let network_graph = Arc::new(NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()));
-               let net_graph_msg_handler = NetGraphMsgHandler::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
+               let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
+               let network_graph = Arc::new(NetworkGraph::new(genesis_hash, Arc::clone(&logger)));
+               let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
                // Build network from our_id to node6:
                //
                //        -1(1)2-  node0  -1(3)2-
@@ -2152,8 +2154,8 @@ mod tests {
 
                let (our_privkey, _, privkeys, _) = get_nodes(&secp_ctx);
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[0], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[0], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 1,
                        timestamp: 1,
@@ -2166,10 +2168,10 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 1,
@@ -2181,7 +2183,7 @@ mod tests {
                        fee_proportional_millionths: u32::max_value(),
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 1,
@@ -2194,10 +2196,10 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[7], ChannelFeatures::from_le_bytes(id_to_feature_flags(12)), 12);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[7], ChannelFeatures::from_le_bytes(id_to_feature_flags(12)), 12);
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 12,
                        timestamp: 1,
@@ -2209,7 +2211,7 @@ mod tests {
                        fee_proportional_millionths: u32::max_value(),
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 12,
                        timestamp: 1,
@@ -2222,10 +2224,10 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[7], NodeFeatures::from_le_bytes(id_to_feature_flags(8)), 0);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], NodeFeatures::from_le_bytes(id_to_feature_flags(8)), 0);
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 3,
                        timestamp: 1,
@@ -2237,7 +2239,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 3,
                        timestamp: 1,
@@ -2250,8 +2252,8 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 4,
                        timestamp: 1,
@@ -2263,7 +2265,7 @@ mod tests {
                        fee_proportional_millionths: 1000000,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 4,
                        timestamp: 1,
@@ -2276,8 +2278,8 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(13)), 13);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[7], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(13)), 13);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 13,
                        timestamp: 1,
@@ -2289,7 +2291,7 @@ mod tests {
                        fee_proportional_millionths: 2000000,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 13,
                        timestamp: 1,
@@ -2302,10 +2304,10 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 6,
                        timestamp: 1,
@@ -2317,7 +2319,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 6,
                        timestamp: 1,
@@ -2330,8 +2332,8 @@ mod tests {
                        excess_data: Vec::new(),
                });
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(11)), 11);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(11)), 11);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 11,
                        timestamp: 1,
@@ -2343,7 +2345,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 11,
                        timestamp: 1,
@@ -2356,12 +2358,12 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(5)), 0);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(5)), 0);
 
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[5], ChannelFeatures::from_le_bytes(id_to_feature_flags(7)), 7);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[5], ChannelFeatures::from_le_bytes(id_to_feature_flags(7)), 7);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 7,
                        timestamp: 1,
@@ -2373,7 +2375,7 @@ mod tests {
                        fee_proportional_millionths: 1000000,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[5], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[5], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 7,
                        timestamp: 1,
@@ -2386,9 +2388,9 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[5], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[5], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
 
-               (secp_ctx, network_graph, net_graph_msg_handler, chain_monitor, logger)
+               (secp_ctx, network_graph, gossip_sync, chain_monitor, logger)
        }
 
        #[test]
@@ -2448,7 +2450,7 @@ mod tests {
 
        #[test]
        fn htlc_minimum_test() {
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let payment_params = PaymentParameters::from_node_id(nodes[2]);
                let scorer = test_utils::TestScorer::with_penalty(0);
@@ -2458,7 +2460,7 @@ mod tests {
                // Simple route to 2 via 1
 
                // Disable other paths
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 12,
                        timestamp: 2,
@@ -2470,7 +2472,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 3,
                        timestamp: 2,
@@ -2482,7 +2484,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 13,
                        timestamp: 2,
@@ -2494,7 +2496,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 6,
                        timestamp: 2,
@@ -2506,7 +2508,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 7,
                        timestamp: 2,
@@ -2521,7 +2523,7 @@ mod tests {
 
                // Check against amount_to_transfer_over_msat.
                // Set minimal HTLC of 200_000_000 msat.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 3,
@@ -2536,7 +2538,7 @@ mod tests {
 
                // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
                // be used.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 4,
                        timestamp: 3,
@@ -2555,7 +2557,7 @@ mod tests {
                } else { panic!(); }
 
                // Lift the restriction on the first hop.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 4,
@@ -2575,7 +2577,7 @@ mod tests {
 
        #[test]
        fn htlc_minimum_overpay_test() {
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
                let scorer = test_utils::TestScorer::with_penalty(0);
@@ -2585,7 +2587,7 @@ mod tests {
                // A route to node#2 via two paths.
                // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
                // Thus, they can't send 60 without overpaying.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 2,
@@ -2597,7 +2599,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 12,
                        timestamp: 3,
@@ -2611,7 +2613,7 @@ mod tests {
                });
 
                // Make 0 fee.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 13,
                        timestamp: 2,
@@ -2623,7 +2625,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 4,
                        timestamp: 2,
@@ -2637,7 +2639,7 @@ mod tests {
                });
 
                // Disable other paths
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 1,
                        timestamp: 3,
@@ -2658,7 +2660,7 @@ mod tests {
 
                // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
                // while taking even more fee to match htlc_minimum_msat.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 12,
                        timestamp: 4,
@@ -2670,7 +2672,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 3,
@@ -2682,7 +2684,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 4,
                        timestamp: 4,
@@ -2713,7 +2715,7 @@ mod tests {
 
        #[test]
        fn disable_channels_test() {
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let payment_params = PaymentParameters::from_node_id(nodes[2]);
                let scorer = test_utils::TestScorer::with_penalty(0);
@@ -2721,7 +2723,7 @@ mod tests {
                let random_seed_bytes = keys_manager.get_secure_random_bytes();
 
                // // Disable channels 4 and 12 by flags=2
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 4,
                        timestamp: 2,
@@ -2733,7 +2735,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 12,
                        timestamp: 2,
@@ -2773,7 +2775,7 @@ mod tests {
 
        #[test]
        fn disable_node_test() {
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let payment_params = PaymentParameters::from_node_id(nodes[2]);
                let scorer = test_utils::TestScorer::with_penalty(0);
@@ -2783,9 +2785,9 @@ mod tests {
                // Disable nodes 1, 2, and 8 by requiring unknown feature bits
                let mut unknown_features = NodeFeatures::known();
                unknown_features.set_unknown_feature_required();
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
 
                // If all nodes require some features we don't understand, route should fail
                if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
@@ -3128,7 +3130,7 @@ mod tests {
 
        #[test]
        fn multi_hint_last_hops_test() {
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
                let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
@@ -3139,7 +3141,7 @@ mod tests {
                // Test shows that multiple hop hints are considered.
 
                // Disabling channels 6 & 7 by flags=2
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 6,
                        timestamp: 2,
@@ -3151,7 +3153,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 7,
                        timestamp: 2,
@@ -3198,7 +3200,7 @@ mod tests {
 
        #[test]
        fn private_multi_hint_last_hops_test() {
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
 
                let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
@@ -3211,7 +3213,7 @@ mod tests {
                // Test shows that multiple hop hints are considered.
 
                // Disabling channels 6 & 7 by flags=2
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 6,
                        timestamp: 2,
@@ -3223,7 +3225,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 7,
                        timestamp: 2,
@@ -3489,8 +3491,12 @@ mod tests {
                let scorer = test_utils::TestScorer::with_penalty(0);
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
                let random_seed_bytes = keys_manager.get_secure_random_bytes();
-               get_route(&source_node_id, &payment_params, &NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()).read_only(),
-                               Some(&our_chans.iter().collect::<Vec<_>>()), route_val, 42, &test_utils::TestLogger::new(), &scorer, &random_seed_bytes)
+               let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
+               let logger = test_utils::TestLogger::new();
+               let network_graph = NetworkGraph::new(genesis_hash, &logger);
+               let route = get_route(&source_node_id, &payment_params, &network_graph.read_only(),
+                               Some(&our_chans.iter().collect::<Vec<_>>()), route_val, 42, &logger, &scorer, &random_seed_bytes);
+               route
        }
 
        #[test]
@@ -3541,7 +3547,7 @@ mod tests {
        fn available_amount_while_routing_test() {
                // Tests whether we choose the correct available channel amount while routing.
 
-               let (secp_ctx, network_graph, mut net_graph_msg_handler, chain_monitor, logger) = build_graph();
+               let (secp_ctx, network_graph, mut gossip_sync, chain_monitor, logger) = build_graph();
                let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let scorer = test_utils::TestScorer::with_penalty(0);
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
@@ -3552,7 +3558,7 @@ mod tests {
                // our node to node2 via node0: channels {1, 3}.
 
                // First disable all other paths.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 2,
@@ -3564,7 +3570,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 12,
                        timestamp: 2,
@@ -3579,7 +3585,7 @@ mod tests {
 
                // Make the first channel (#1) very permissive,
                // and we will be testing all limits on the second channel.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 1,
                        timestamp: 2,
@@ -3594,7 +3600,7 @@ mod tests {
 
                // First, let's see if routing works if we have absolutely no idea about the available amount.
                // In this case, it should be set to 250_000 sats.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 3,
                        timestamp: 2,
@@ -3627,7 +3633,7 @@ mod tests {
 
                // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
                // Disable channel #1 and use another first hop.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 1,
                        timestamp: 3,
@@ -3662,7 +3668,7 @@ mod tests {
                }
 
                // Enable channel #1 back.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 1,
                        timestamp: 4,
@@ -3677,7 +3683,7 @@ mod tests {
 
 
                // Now let's see if routing works if we know only htlc_maximum_msat.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 3,
                        timestamp: 3,
@@ -3712,7 +3718,7 @@ mod tests {
 
                // We can't change UTXO capacity on the fly, so we'll disable
                // the existing channel and add another one with the capacity we need.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 3,
                        timestamp: 4,
@@ -3732,10 +3738,10 @@ mod tests {
                .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
 
                *chain_monitor.utxo_ret.lock().unwrap() = Ok(TxOut { value: 15, script_pubkey: good_script.clone() });
-               net_graph_msg_handler.add_chain_access(Some(chain_monitor));
+               gossip_sync.add_chain_access(Some(chain_monitor));
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 333,
                        timestamp: 1,
@@ -3747,7 +3753,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 333,
                        timestamp: 1,
@@ -3779,7 +3785,7 @@ mod tests {
                }
 
                // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 333,
                        timestamp: 6,
@@ -3815,7 +3821,7 @@ mod tests {
        fn available_liquidity_last_hop_test() {
                // Check that available liquidity properly limits the path even when only
                // one of the latter hops is limited.
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let scorer = test_utils::TestScorer::with_penalty(0);
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
@@ -3827,7 +3833,7 @@ mod tests {
                // Total capacity: 50 sats.
 
                // Disable other potential paths.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 2,
@@ -3839,7 +3845,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 7,
                        timestamp: 2,
@@ -3854,7 +3860,7 @@ mod tests {
 
                // Limit capacities
 
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 12,
                        timestamp: 2,
@@ -3866,7 +3872,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 13,
                        timestamp: 2,
@@ -3879,7 +3885,7 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 6,
                        timestamp: 2,
@@ -3891,7 +3897,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 11,
                        timestamp: 2,
@@ -3940,7 +3946,7 @@ mod tests {
 
        #[test]
        fn ignore_fee_first_hop_test() {
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let scorer = test_utils::TestScorer::with_penalty(0);
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
@@ -3948,7 +3954,7 @@ mod tests {
                let payment_params = PaymentParameters::from_node_id(nodes[2]);
 
                // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 1,
                        timestamp: 2,
@@ -3960,7 +3966,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 3,
                        timestamp: 2,
@@ -3988,7 +3994,7 @@ mod tests {
 
        #[test]
        fn simple_mpp_route_test() {
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let scorer = test_utils::TestScorer::with_penalty(0);
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
@@ -4004,7 +4010,7 @@ mod tests {
                // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
 
                // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 1,
                        timestamp: 2,
@@ -4016,7 +4022,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 3,
                        timestamp: 2,
@@ -4031,7 +4037,7 @@ mod tests {
 
                // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
                // (total limit 60).
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 12,
                        timestamp: 2,
@@ -4043,7 +4049,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 13,
                        timestamp: 2,
@@ -4058,7 +4064,7 @@ mod tests {
 
                // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
                // (total capacity 180 sats).
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 2,
@@ -4070,7 +4076,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 4,
                        timestamp: 2,
@@ -4121,7 +4127,7 @@ mod tests {
 
        #[test]
        fn long_mpp_route_test() {
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let scorer = test_utils::TestScorer::with_penalty(0);
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
@@ -4136,7 +4142,7 @@ mod tests {
                // are used twice will have 200 sats capacity.
 
                // Disable other potential paths.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 2,
@@ -4148,7 +4154,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 7,
                        timestamp: 2,
@@ -4162,7 +4168,7 @@ mod tests {
                });
 
                // Path via {node0, node2} is channels {1, 3, 5}.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 1,
                        timestamp: 2,
@@ -4174,7 +4180,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 3,
                        timestamp: 2,
@@ -4188,8 +4194,8 @@ mod tests {
                });
 
                // Capacity of 200 sats because this channel will be used by 3rd path as well.
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 5,
                        timestamp: 2,
@@ -4205,7 +4211,7 @@ mod tests {
                // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
                // Add 100 sats to the capacities of {12, 13}, because these channels
                // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 12,
                        timestamp: 2,
@@ -4217,7 +4223,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 13,
                        timestamp: 2,
@@ -4230,7 +4236,7 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 6,
                        timestamp: 2,
@@ -4242,7 +4248,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 11,
                        timestamp: 2,
@@ -4285,7 +4291,7 @@ mod tests {
 
        #[test]
        fn mpp_cheaper_route_test() {
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let scorer = test_utils::TestScorer::with_penalty(0);
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
@@ -4304,7 +4310,7 @@ mod tests {
                // are used twice will have 200 sats capacity.
 
                // Disable other potential paths.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 2,
@@ -4316,7 +4322,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 7,
                        timestamp: 2,
@@ -4330,7 +4336,7 @@ mod tests {
                });
 
                // Path via {node0, node2} is channels {1, 3, 5}.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 1,
                        timestamp: 2,
@@ -4342,7 +4348,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 3,
                        timestamp: 2,
@@ -4356,8 +4362,8 @@ mod tests {
                });
 
                // Capacity of 200 sats because this channel will be used by 3rd path as well.
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 5,
                        timestamp: 2,
@@ -4373,7 +4379,7 @@ mod tests {
                // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
                // Add 100 sats to the capacities of {12, 13}, because these channels
                // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 12,
                        timestamp: 2,
@@ -4385,7 +4391,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 13,
                        timestamp: 2,
@@ -4398,7 +4404,7 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 6,
                        timestamp: 2,
@@ -4410,7 +4416,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 11,
                        timestamp: 2,
@@ -4454,7 +4460,7 @@ mod tests {
                // This test makes sure that MPP algorithm properly takes into account
                // fees charged on the channels, by making the fees impactful:
                // if the fee is not properly accounted for, the behavior is different.
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let scorer = test_utils::TestScorer::with_penalty(0);
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
@@ -4471,7 +4477,7 @@ mod tests {
                // It's fine to ignore this concern for now.
 
                // Disable other potential paths.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 2,
@@ -4484,7 +4490,7 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 7,
                        timestamp: 2,
@@ -4498,7 +4504,7 @@ mod tests {
                });
 
                // Path via {node0, node2} is channels {1, 3, 5}.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 1,
                        timestamp: 2,
@@ -4510,7 +4516,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 3,
                        timestamp: 2,
@@ -4523,8 +4529,8 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 5,
                        timestamp: 2,
@@ -4547,7 +4553,7 @@ mod tests {
                // - channel 12 capacity is 250 sats
                // - fee for channel 6 is 150 sats
                // Let's test this by enforcing these 2 conditions and removing other limits.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 12,
                        timestamp: 2,
@@ -4559,7 +4565,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 13,
                        timestamp: 2,
@@ -4572,7 +4578,7 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 6,
                        timestamp: 2,
@@ -4584,7 +4590,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 11,
                        timestamp: 2,
@@ -4635,7 +4641,7 @@ mod tests {
                // to only have the remaining to-collect amount in available liquidity.
                //
                // This bug appeared in production in some specific channel configurations.
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let scorer = test_utils::TestScorer::with_penalty(0);
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
@@ -4655,7 +4661,7 @@ mod tests {
                // would first use the no-fee route and then fail to find a path along the second route as
                // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
                // under 5% of our payment amount.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 1,
                        timestamp: 2,
@@ -4667,7 +4673,7 @@ mod tests {
                        fee_proportional_millionths: u32::max_value(),
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 2,
@@ -4679,7 +4685,7 @@ mod tests {
                        fee_proportional_millionths: u32::max_value(),
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 4,
                        timestamp: 2,
@@ -4691,7 +4697,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 13,
                        timestamp: 2,
@@ -4725,7 +4731,7 @@ mod tests {
        fn drop_lowest_channel_mpp_route_test() {
                // This test checks that low-capacity channel is dropped when after
                // path finding we realize that we found more capacity than we need.
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let scorer = test_utils::TestScorer::with_penalty(0);
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
@@ -4742,7 +4748,7 @@ mod tests {
                // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
 
                // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 1,
                        timestamp: 2,
@@ -4754,7 +4760,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 3,
                        timestamp: 2,
@@ -4768,7 +4774,7 @@ mod tests {
                });
 
                // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 12,
                        timestamp: 2,
@@ -4780,7 +4786,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 13,
                        timestamp: 2,
@@ -4794,7 +4800,7 @@ mod tests {
                });
 
                // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 2,
@@ -4806,7 +4812,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 4,
                        timestamp: 2,
@@ -4882,17 +4888,18 @@ mod tests {
                // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
                // "previous hop" being set to node 3, creating a loop in the path.
                let secp_ctx = Secp256k1::new();
+               let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
                let logger = Arc::new(test_utils::TestLogger::new());
-               let network = Arc::new(NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()));
-               let net_graph_msg_handler = NetGraphMsgHandler::new(Arc::clone(&network), None, Arc::clone(&logger));
+               let network = Arc::new(NetworkGraph::new(genesis_hash, Arc::clone(&logger)));
+               let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
                let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let scorer = test_utils::TestScorer::with_penalty(0);
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
                let random_seed_bytes = keys_manager.get_secure_random_bytes();
                let payment_params = PaymentParameters::from_node_id(nodes[6]);
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 6,
                        timestamp: 1,
@@ -4904,10 +4911,10 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 5,
                        timestamp: 1,
@@ -4919,10 +4926,10 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 4,
                        timestamp: 1,
@@ -4934,10 +4941,10 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 3,
                        timestamp: 1,
@@ -4949,10 +4956,10 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 1,
@@ -4965,8 +4972,8 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
+               add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 1,
                        timestamp: 1,
@@ -4978,7 +4985,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
+               add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
 
                {
                        // Now ensure the route flows simply over nodes 1 and 4 to 6.
@@ -5015,7 +5022,7 @@ mod tests {
                // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
                // for us, including later hop fees, we take it. In the first version of our MPP algorithm
                // we calculated fees on a higher value, resulting in us ignoring such paths.
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
                let scorer = test_utils::TestScorer::with_penalty(0);
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
@@ -5024,7 +5031,7 @@ mod tests {
 
                // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
                // send.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 2,
@@ -5037,7 +5044,7 @@ mod tests {
                        excess_data: Vec::new()
                });
 
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 12,
                        timestamp: 2,
@@ -5079,7 +5086,7 @@ mod tests {
                // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
                // initial version of MPP we'd accept such routes but reject them while recalculating fees,
                // resulting in us thinking there is no possible path, even if other paths exist.
-               let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
+               let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
                let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
                let scorer = test_utils::TestScorer::with_penalty(0);
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
@@ -5089,7 +5096,7 @@ mod tests {
                // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
                // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
                // then try to send 90_000.
-               update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 2,
                        timestamp: 2,
@@ -5101,7 +5108,7 @@ mod tests {
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new()
                });
-               update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
+               update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
                        chain_hash: genesis_block(Network::Testnet).header.block_hash(),
                        short_channel_id: 4,
                        timestamp: 2,
@@ -5148,8 +5155,9 @@ mod tests {
                // route over multiple channels with the same first hop.
                let secp_ctx = Secp256k1::new();
                let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
+               let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
                let logger = Arc::new(test_utils::TestLogger::new());
-               let network_graph = NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash());
+               let network_graph = NetworkGraph::new(genesis_hash, Arc::clone(&logger));
                let scorer = test_utils::TestScorer::with_penalty(0);
                let payment_params = PaymentParameters::from_node_id(nodes[0]).with_features(InvoiceFeatures::known());
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
@@ -5587,7 +5595,7 @@ mod tests {
                seed
        }
        #[cfg(not(feature = "no-std"))]
-       use util::ser::Readable;
+       use util::ser::ReadableArgs;
 
        #[test]
        #[cfg(not(feature = "no-std"))]
@@ -5601,7 +5609,8 @@ mod tests {
                                return;
                        },
                };
-               let graph = NetworkGraph::read(&mut d).unwrap();
+               let logger = test_utils::TestLogger::new();
+               let graph = NetworkGraph::read(&mut d, &logger).unwrap();
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
                let random_seed_bytes = keys_manager.get_secure_random_bytes();
 
@@ -5617,7 +5626,6 @@ mod tests {
                                let payment_params = PaymentParameters::from_node_id(dst);
                                let amt = seed as u64 % 200_000_000;
                                let params = ProbabilisticScoringParameters::default();
-                               let logger = test_utils::TestLogger::new();
                                let scorer = ProbabilisticScorer::new(params, &graph, &logger);
                                if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &logger, &scorer, &random_seed_bytes).is_ok() {
                                        continue 'load_endpoints;
@@ -5638,7 +5646,8 @@ mod tests {
                                return;
                        },
                };
-               let graph = NetworkGraph::read(&mut d).unwrap();
+               let logger = test_utils::TestLogger::new();
+               let graph = NetworkGraph::read(&mut d, &logger).unwrap();
                let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
                let random_seed_bytes = keys_manager.get_secure_random_bytes();
 
@@ -5654,7 +5663,6 @@ mod tests {
                                let payment_params = PaymentParameters::from_node_id(dst).with_features(InvoiceFeatures::known());
                                let amt = seed as u64 % 200_000_000;
                                let params = ProbabilisticScoringParameters::default();
-                               let logger = test_utils::TestLogger::new();
                                let scorer = ProbabilisticScorer::new(params, &graph, &logger);
                                if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &logger, &scorer, &random_seed_bytes).is_ok() {
                                        continue 'load_endpoints;
@@ -5700,9 +5708,10 @@ mod benches {
        use chain::keysinterface::{KeysManager,KeysInterface};
        use ln::channelmanager::{ChannelCounterparty, ChannelDetails};
        use ln::features::{InitFeatures, InvoiceFeatures};
-       use routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringParameters, Scorer};
+       use routing::gossip::NetworkGraph;
+       use routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringParameters};
        use util::logger::{Logger, Record};
-       use util::test_utils::TestLogger;
+       use util::ser::ReadableArgs;
 
        use test::Bencher;
 
@@ -5711,9 +5720,9 @@ mod benches {
                fn log(&self, _record: &Record) {}
        }
 
-       fn read_network_graph() -> NetworkGraph {
+       fn read_network_graph(logger: &DummyLogger) -> NetworkGraph<&DummyLogger> {
                let mut d = test_utils::get_route_file().unwrap();
-               NetworkGraph::read(&mut d).unwrap()
+               NetworkGraph::read(&mut d, logger).unwrap()
        }
 
        fn payer_pubkey() -> PublicKey {
@@ -5760,36 +5769,24 @@ mod benches {
 
        #[bench]
        fn generate_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
-               let network_graph = read_network_graph();
+               let logger = DummyLogger {};
+               let network_graph = read_network_graph(&logger);
                let scorer = FixedPenaltyScorer::with_penalty(0);
                generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
        }
 
        #[bench]
        fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
-               let network_graph = read_network_graph();
+               let logger = DummyLogger {};
+               let network_graph = read_network_graph(&logger);
                let scorer = FixedPenaltyScorer::with_penalty(0);
                generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
        }
 
-       #[bench]
-       fn generate_routes_with_default_scorer(bench: &mut Bencher) {
-               let network_graph = read_network_graph();
-               let scorer = Scorer::default();
-               generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
-       }
-
-       #[bench]
-       fn generate_mpp_routes_with_default_scorer(bench: &mut Bencher) {
-               let network_graph = read_network_graph();
-               let scorer = Scorer::default();
-               generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
-       }
-
        #[bench]
        fn generate_routes_with_probabilistic_scorer(bench: &mut Bencher) {
-               let logger = TestLogger::new();
-               let network_graph = read_network_graph();
+               let logger = DummyLogger {};
+               let network_graph = read_network_graph(&logger);
                let params = ProbabilisticScoringParameters::default();
                let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
                generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
@@ -5797,15 +5794,16 @@ mod benches {
 
        #[bench]
        fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Bencher) {
-               let logger = TestLogger::new();
-               let network_graph = read_network_graph();
+               let logger = DummyLogger {};
+               let network_graph = read_network_graph(&logger);
                let params = ProbabilisticScoringParameters::default();
                let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
                generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
        }
 
        fn generate_routes<S: Score>(
-               bench: &mut Bencher, graph: &NetworkGraph, mut scorer: S, features: InvoiceFeatures
+               bench: &mut Bencher, graph: &NetworkGraph<&DummyLogger>, mut scorer: S,
+               features: InvoiceFeatures
        ) {
                let nodes = graph.read_only().nodes().clone();
                let payer = payer_pubkey();