Avoid persisting a ChannelManager update after each timer tick
authorMatt Corallo <git@bluematt.me>
Fri, 7 May 2021 22:16:47 +0000 (22:16 +0000)
committerMatt Corallo <git@bluematt.me>
Fri, 14 May 2021 23:20:27 +0000 (23:20 +0000)
Currently, when a user calls `ChannelManager::timer_tick_occurred`
we always set the persister's update flag to true. This results in
a ChannelManager persistence after each timer tick, even when
nothing happened.

Instead, we add a new flag to `PersistenceNotifierGuard` to
indicate if we should skip setting the update flag.

lightning/src/ln/channelmanager.rs

index 6d1c73e59826ea5ae46b9e4f656f347c3c40d56c..9efb6b83b8a2ad3355a392b6203f00f5cd077607 100644 (file)
@@ -468,8 +468,8 @@ pub struct ChannelManager<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref,
        /// Essentially just when we're serializing ourselves out.
        /// Taken first everywhere where we are making changes before any other locks.
        /// When acquiring this lock in read mode, rather than acquiring it directly, call
-       /// `PersistenceNotifierGuard::new(..)` and pass the lock to it, to ensure the PersistenceNotifier
-       /// the lock contains sends out a notification when the lock is released.
+       /// `PersistenceNotifierGuard::notify_on_drop(..)` and pass the lock to it, to ensure the
+       /// PersistenceNotifier the lock contains sends out a notification when the lock is released.
        total_consistency_lock: RwLock<()>,
 
        persistence_notifier: PersistenceNotifier,
@@ -522,32 +522,50 @@ impl BestBlock {
        pub fn height(&self) -> u32 { self.height }
 }
 
+#[derive(Copy, Clone, PartialEq)]
+enum NotifyOption {
+       DoPersist,
+       SkipPersist,
+}
+
 /// Whenever we release the `ChannelManager`'s `total_consistency_lock`, from read mode, it is
 /// desirable to notify any listeners on `await_persistable_update_timeout`/
-/// `await_persistable_update` that new updates are available for persistence. Therefore, this
+/// `await_persistable_update` when new updates are available for persistence. Therefore, this
 /// struct is responsible for locking the total consistency lock and, upon going out of scope,
 /// sending the aforementioned notification (since the lock being released indicates that the
 /// updates are ready for persistence).
-struct PersistenceNotifierGuard<'a> {
+///
+/// We allow callers to either always notify by constructing with `notify_on_drop` or choose to
+/// notify or not based on whether relevant changes have been made, providing a closure to
+/// `optionally_notify` which returns a `NotifyOption`.
+struct PersistenceNotifierGuard<'a, F: Fn() -> NotifyOption> {
        persistence_notifier: &'a PersistenceNotifier,
+       should_persist: F,
        // We hold onto this result so the lock doesn't get released immediately.
        _read_guard: RwLockReadGuard<'a, ()>,
 }
 
-impl<'a> PersistenceNotifierGuard<'a> {
-       fn new(lock: &'a RwLock<()>, notifier: &'a PersistenceNotifier) -> Self {
+impl<'a> PersistenceNotifierGuard<'a, fn() -> NotifyOption> { // We don't care what the concrete F is here, it's unused
+       fn notify_on_drop(lock: &'a RwLock<()>, notifier: &'a PersistenceNotifier) -> PersistenceNotifierGuard<'a, impl Fn() -> NotifyOption> {
+               PersistenceNotifierGuard::optionally_notify(lock, notifier, || -> NotifyOption { NotifyOption::DoPersist })
+       }
+
+       fn optionally_notify<F: Fn() -> NotifyOption>(lock: &'a RwLock<()>, notifier: &'a PersistenceNotifier, persist_check: F) -> PersistenceNotifierGuard<'a, F> {
                let read_guard = lock.read().unwrap();
 
-               Self {
+               PersistenceNotifierGuard {
                        persistence_notifier: notifier,
+                       should_persist: persist_check,
                        _read_guard: read_guard,
                }
        }
 }
 
-impl<'a> Drop for PersistenceNotifierGuard<'a> {
+impl<'a, F: Fn() -> NotifyOption> Drop for PersistenceNotifierGuard<'a, F> {
        fn drop(&mut self) {
-               self.persistence_notifier.notify();
+               if (self.should_persist)() == NotifyOption::DoPersist {
+                       self.persistence_notifier.notify();
+               }
        }
 }
 
@@ -943,7 +961,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                let channel = Channel::new_outbound(&self.fee_estimator, &self.keys_manager, their_network_key, channel_value_satoshis, push_msat, user_id, config)?;
                let res = channel.get_open_channel(self.genesis_hash.clone());
 
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                // We want to make sure the lock is actually acquired by PersistenceNotifierGuard.
                debug_assert!(&self.total_consistency_lock.try_write().is_err());
 
@@ -1024,7 +1042,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        ///
        /// May generate a SendShutdown message event on success, which should be relayed.
        pub fn close_channel(&self, channel_id: &[u8; 32]) -> Result<(), APIError> {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
 
                let (mut failed_htlcs, chan_option) = {
                        let mut channel_state_lock = self.channel_state.lock().unwrap();
@@ -1114,7 +1132,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// Force closes a channel, immediately broadcasting the latest local commitment transaction to
        /// the chain and rejecting new HTLCs on the given channel. Fails if channel_id is unknown to the manager.
        pub fn force_close_channel(&self, channel_id: &[u8; 32]) -> Result<(), APIError> {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                match self.force_close_channel_with_peer(channel_id, None) {
                        Ok(counterparty_node_id) => {
                                self.channel_state.lock().unwrap().pending_msg_events.push(
@@ -1459,7 +1477,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                }
                let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, prng_seed, payment_hash);
 
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
 
                let err: Result<(), _> = loop {
                        let mut channel_lock = self.channel_state.lock().unwrap();
@@ -1686,7 +1704,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// not currently support replacing a funding transaction on an existing channel. Instead,
        /// create a new channel with a conflicting funding transaction.
        pub fn funding_transaction_generated(&self, temporary_channel_id: &[u8; 32], funding_transaction: Transaction) -> Result<(), APIError> {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
 
                for inp in funding_transaction.input.iter() {
                        if inp.witness.is_empty() {
@@ -1769,7 +1787,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        ///
        /// Panics if addresses is absurdly large (more than 500).
        pub fn broadcast_node_announcement(&self, rgb: [u8; 3], alias: [u8; 32], mut addresses: Vec<NetAddress>) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
 
                if addresses.len() > 500 {
                        panic!("More than half the message size was taken up by public addresses!");
@@ -1803,7 +1821,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// Should only really ever be called in response to a PendingHTLCsForwardable event.
        /// Will likely generate further events.
        pub fn process_pending_htlc_forwards(&self) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
 
                let mut new_events = Vec::new();
                let mut failed_forwards = Vec::new();
@@ -2094,9 +2112,13 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// BroadcastChannelUpdate events in timer_tick_occurred.
        ///
        /// Expects the caller to have a total_consistency_lock read lock.
-       fn process_background_events(&self) {
+       fn process_background_events(&self) -> bool {
                let mut background_events = Vec::new();
                mem::swap(&mut *self.pending_background_events.lock().unwrap(), &mut background_events);
+               if background_events.is_empty() {
+                       return false;
+               }
+
                for event in background_events.drain(..) {
                        match event {
                                BackgroundEvent::ClosingMonitorUpdate((funding_txo, update)) => {
@@ -2106,6 +2128,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                },
                        }
                }
+               true
        }
 
        #[cfg(any(test, feature = "_test_utils"))]
@@ -2121,36 +2144,42 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        ///
        /// Note that in some rare cases this may generate a `chain::Watch::update_channel` call.
        pub fn timer_tick_occurred(&self) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
-               self.process_background_events();
+               PersistenceNotifierGuard::optionally_notify(&self.total_consistency_lock, &self.persistence_notifier, || {
+                       let mut should_persist = NotifyOption::SkipPersist;
+                       if self.process_background_events() { should_persist = NotifyOption::DoPersist; }
 
-               let mut channel_state_lock = self.channel_state.lock().unwrap();
-               let channel_state = &mut *channel_state_lock;
-               for (_, chan) in channel_state.by_id.iter_mut() {
-                       match chan.get_update_status() {
-                               UpdateStatus::Enabled if !chan.is_live() => chan.set_update_status(UpdateStatus::DisabledStaged),
-                               UpdateStatus::Disabled if chan.is_live() => chan.set_update_status(UpdateStatus::EnabledStaged),
-                               UpdateStatus::DisabledStaged if chan.is_live() => chan.set_update_status(UpdateStatus::Enabled),
-                               UpdateStatus::EnabledStaged if !chan.is_live() => chan.set_update_status(UpdateStatus::Disabled),
-                               UpdateStatus::DisabledStaged if !chan.is_live() => {
-                                       if let Ok(update) = self.get_channel_update(&chan) {
-                                               channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
-                                                       msg: update
-                                               });
-                                       }
-                                       chan.set_update_status(UpdateStatus::Disabled);
-                               },
-                               UpdateStatus::EnabledStaged if chan.is_live() => {
-                                       if let Ok(update) = self.get_channel_update(&chan) {
-                                               channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
-                                                       msg: update
-                                               });
-                                       }
-                                       chan.set_update_status(UpdateStatus::Enabled);
-                               },
-                               _ => {},
+                       let mut channel_state_lock = self.channel_state.lock().unwrap();
+                       let channel_state = &mut *channel_state_lock;
+                       for (_, chan) in channel_state.by_id.iter_mut() {
+                               match chan.get_update_status() {
+                                       UpdateStatus::Enabled if !chan.is_live() => chan.set_update_status(UpdateStatus::DisabledStaged),
+                                       UpdateStatus::Disabled if chan.is_live() => chan.set_update_status(UpdateStatus::EnabledStaged),
+                                       UpdateStatus::DisabledStaged if chan.is_live() => chan.set_update_status(UpdateStatus::Enabled),
+                                       UpdateStatus::EnabledStaged if !chan.is_live() => chan.set_update_status(UpdateStatus::Disabled),
+                                       UpdateStatus::DisabledStaged if !chan.is_live() => {
+                                               if let Ok(update) = self.get_channel_update(&chan) {
+                                                       channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
+                                                               msg: update
+                                                       });
+                                               }
+                                               should_persist = NotifyOption::DoPersist;
+                                               chan.set_update_status(UpdateStatus::Disabled);
+                                       },
+                                       UpdateStatus::EnabledStaged if chan.is_live() => {
+                                               if let Ok(update) = self.get_channel_update(&chan) {
+                                                       channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
+                                                               msg: update
+                                                       });
+                                               }
+                                               should_persist = NotifyOption::DoPersist;
+                                               chan.set_update_status(UpdateStatus::Enabled);
+                                       },
+                                       _ => {},
+                               }
                        }
-               }
+
+                       should_persist
+               });
        }
 
        /// Indicates that the preimage for payment_hash is unknown or the received amount is incorrect
@@ -2159,7 +2188,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// Returns false if no payment was found to fail backwards, true if the process of failing the
        /// HTLC backwards has been started.
        pub fn fail_htlc_backwards(&self, payment_hash: &PaymentHash) -> bool {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
 
                let mut channel_state = Some(self.channel_state.lock().unwrap());
                let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(payment_hash);
@@ -2339,7 +2368,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        pub fn claim_funds(&self, payment_preimage: PaymentPreimage) -> bool {
                let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
 
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
 
                let mut channel_state = Some(self.channel_state.lock().unwrap());
                let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(&payment_hash);
@@ -2523,7 +2552,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        ///  4) once all remote copies are updated, you call this function with the update_id that
        ///     completed, and once it is the latest the Channel will be re-enabled.
        pub fn channel_monitor_updated(&self, funding_txo: &OutPoint, highest_applied_update_id: u64) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
 
                let mut close_results = Vec::new();
                let mut htlc_forwards = Vec::new();
@@ -3294,7 +3323,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// (C-not exported) Cause its doc(hidden) anyway
        #[doc(hidden)]
        pub fn update_fee(&self, channel_id: [u8;32], feerate_per_kw: u32) -> Result<(), APIError> {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let counterparty_node_id;
                let err: Result<(), _> = loop {
                        let mut channel_state_lock = self.channel_state.lock().unwrap();
@@ -3418,7 +3447,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 
                let payment_secret = PaymentSecret(self.keys_manager.get_secure_random_bytes());
 
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let mut payment_secrets = self.pending_inbound_payments.lock().unwrap();
                match payment_secrets.entry(payment_hash) {
                        hash_map::Entry::Vacant(e) => {
@@ -3575,7 +3604,7 @@ where
        }
 
        fn block_disconnected(&self, header: &BlockHeader, height: u32) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let new_height = height - 1;
                {
                        let mut best_block = self.best_block.write().unwrap();
@@ -3606,7 +3635,7 @@ where
                let block_hash = header.block_hash();
                log_trace!(self.logger, "{} transactions included in block {} at height {} provided", txdata.len(), block_hash, height);
 
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                self.do_chain_event(Some(height), |channel| channel.transactions_confirmed(&block_hash, height, txdata, &self.logger).map(|a| (a, Vec::new())));
        }
 
@@ -3618,7 +3647,7 @@ where
                let block_hash = header.block_hash();
                log_trace!(self.logger, "New best block: {} at height {}", block_hash, height);
 
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
 
                *self.best_block.write().unwrap() = BestBlock::new(block_hash, height);
 
@@ -3660,7 +3689,7 @@ where
        }
 
        fn transaction_unconfirmed(&self, txid: &Txid) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                self.do_chain_event(None, |channel| {
                        if let Some(funding_txo) = channel.get_funding_txo() {
                                if funding_txo.txid == *txid {
@@ -3806,92 +3835,92 @@ impl<Signer: Sign, M: Deref , T: Deref , K: Deref , F: Deref , L: Deref >
         L::Target: Logger,
 {
        fn handle_open_channel(&self, counterparty_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_open_channel(counterparty_node_id, their_features, msg), *counterparty_node_id);
        }
 
        fn handle_accept_channel(&self, counterparty_node_id: &PublicKey, their_features: InitFeatures, msg: &msgs::AcceptChannel) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_accept_channel(counterparty_node_id, their_features, msg), *counterparty_node_id);
        }
 
        fn handle_funding_created(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingCreated) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_funding_created(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_funding_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingSigned) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_funding_signed(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_funding_locked(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingLocked) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_funding_locked(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_shutdown(&self, counterparty_node_id: &PublicKey, their_features: &InitFeatures, msg: &msgs::Shutdown) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_shutdown(counterparty_node_id, their_features, msg), *counterparty_node_id);
        }
 
        fn handle_closing_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::ClosingSigned) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_closing_signed(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_update_add_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_update_add_htlc(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_update_fulfill_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_update_fulfill_htlc(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_update_fail_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_update_fail_htlc(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_update_fail_malformed_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_update_fail_malformed_htlc(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_commitment_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::CommitmentSigned) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_commitment_signed(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_revoke_and_ack(&self, counterparty_node_id: &PublicKey, msg: &msgs::RevokeAndACK) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_revoke_and_ack(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_update_fee(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFee) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_update_fee(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_announcement_signatures(&self, counterparty_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_announcement_signatures(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_channel_update(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelUpdate) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_channel_update(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_channel_reestablish(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelReestablish) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let _ = handle_error!(self, self.internal_channel_reestablish(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn peer_disconnected(&self, counterparty_node_id: &PublicKey, no_connection_possible: bool) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
                let mut failed_channels = Vec::new();
                let mut failed_payments = Vec::new();
                let mut no_channels_remain = true;
@@ -3984,7 +4013,7 @@ impl<Signer: Sign, M: Deref , T: Deref , K: Deref , F: Deref , L: Deref >
        fn peer_connected(&self, counterparty_node_id: &PublicKey, init_msg: &msgs::Init) {
                log_debug!(self.logger, "Generating channel_reestablish events for {}", log_pubkey!(counterparty_node_id));
 
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
 
                {
                        let mut peer_state_lock = self.per_peer_state.write().unwrap();
@@ -4024,7 +4053,7 @@ impl<Signer: Sign, M: Deref , T: Deref , K: Deref , F: Deref , L: Deref >
        }
 
        fn handle_error(&self, counterparty_node_id: &PublicKey, msg: &msgs::ErrorMessage) {
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
 
                if msg.channel_id == [0; 32] {
                        for chan in self.list_channels() {