Simulation unhappy path (#193)

* Use elapsed time

* Added timeout

* Extract tally

* Missing elapsed time

* Fix new view leader behaviour

* Fix tests

* Fix timeout double check

* Fix logs

* TimeoutHandler nitpicks

* Clippy happy

* Fix timeout sub

* Modify discard messages comment

simulations/src/node/carnot/event_builder.rs

@@ -1,11 +1,14 @@
-use crate::node::carnot::messages::CarnotMessage;
+use crate::node::carnot::{messages::CarnotMessage, tally::Tally, timeout::TimeoutHandler};
 use crate::util::parse_idx;
-use consensus_engine::{Carnot, NewView, Overlay, Qc, StandardQc, Timeout, TimeoutQc, View, Vote};
+use consensus_engine::{
+    AggregateQc, Carnot, NewView, Overlay, Qc, StandardQc, Timeout, TimeoutQc, View, Vote,
+};
 use nomos_consensus::network::messages::{NewViewMsg, TimeoutMsg, VoteMsg};
 use nomos_consensus::NodeId;
 use nomos_core::block::Block;
-use std::collections::{HashMap, HashSet};
+use std::collections::HashSet;
 use std::hash::Hash;
+use std::time::Duration;
 
 pub type CarnotTx = [u8; 32];
 
@@ -14,28 +17,54 @@ pub(crate) struct EventBuilder {
     leader_vote_message: Tally<VoteMsg>,
     vote_message: Tally<VoteMsg>,
     timeout_message: Tally<TimeoutMsg>,
+    leader_new_view_message: Tally<NewViewMsg>,
     new_view_message: Tally<NewViewMsg>,
+    timeout_handler: TimeoutHandler,
     pub(crate) current_view: View,
 }
 
 impl EventBuilder {
-    pub fn new(id: NodeId) -> Self {
+    pub fn new(id: NodeId, timeout: Duration) -> Self {
         Self {
             vote_message: Default::default(),
             leader_vote_message: Default::default(),
             timeout_message: Default::default(),
+            leader_new_view_message: Default::default(),
             new_view_message: Default::default(),
             current_view: View::default(),
             id,
+            timeout_handler: TimeoutHandler::new(timeout),
+        }
+    }
+
+    fn local_timeout(&mut self, view: View, elapsed: Duration) -> bool {
+        if self.timeout_handler.step(view, elapsed) {
+            self.timeout_handler.prune_by_view(view);
+            true
+        } else {
+            false
         }
     }
 
     pub fn step<O: Overlay>(
         &mut self,
-        messages: Vec<CarnotMessage>,
+        mut messages: Vec<CarnotMessage>,
         engine: &Carnot<O>,
+        elapsed: Duration,
     ) -> Vec<Event<CarnotTx>> {
         let mut events = Vec::new();
+        // check timeout and exit
+        if self.local_timeout(engine.current_view(), elapsed) {
+            events.push(Event::LocalTimeout);
+            // if we timeout discard incoming current view messages
+            messages.retain(|msg| {
+                matches!(
+                    msg,
+                    CarnotMessage::Proposal(_) | CarnotMessage::TimeoutQc(_)
+                )
+            });
+        }
+
         // only run when the engine is in the genesis view
         if engine.highest_voted_view() == -1
             && engine.overlay().is_member_of_leaf_committee(self.id)
@@ -67,7 +96,14 @@ impl EventBuilder {
                     events.push(Event::Proposal { block })
                 }
                 CarnotMessage::TimeoutQc(msg) => {
+                    let timeout_qc = msg.qc.clone();
                     events.push(Event::TimeoutQc { timeout_qc: msg.qc });
+                    if engine.overlay().is_member_of_leaf_committee(self.id) {
+                        events.push(Event::NewView {
+                            timeout_qc,
+                            new_views: Default::default(),
+                        });
+                    }
                 }
                 CarnotMessage::Vote(msg) => {
                     let msg_view = msg.vote.view;
@@ -138,64 +174,46 @@ impl EventBuilder {
                 }
                 CarnotMessage::NewView(msg) => {
                     let msg_view = msg.vote.view;
+                    let voter = msg.voter;
                     let timeout_qc = msg.vote.timeout_qc.clone();
-                    self.current_view = core::cmp::max(self.current_view, msg_view);
+                    let is_next_view_leader = engine.is_next_leader();
-                    // if we are the leader, then use the leader threshold, otherwise use the leaf threshold
+                    let is_message_from_root_committee =
-                    let threshold = if engine.is_next_leader() {
+                        engine.overlay().is_member_of_root_committee(voter);
+
+                    let tally = if is_message_from_root_committee {
+                        &mut self.leader_new_view_message
+                    } else {
+                        &mut self.new_view_message
+                    };
+
+                    // if the message comes from the root committee, then use the leader threshold, otherwise use the leaf threshold
+                    let threshold = if is_message_from_root_committee {
                         engine.leader_super_majority_threshold()
                     } else {
                         engine.super_majority_threshold()
                     };
 
-                    if let Some(new_views) =
+                    if let Some(votes) = tally.tally_by(msg_view, msg, threshold) {
-                        self.new_view_message.tally_by(msg_view, msg, threshold)
+                        if is_next_view_leader && is_message_from_root_committee {
-                    {
+                            let high_qc = engine.high_qc();
-                        events.push(Event::NewView {
+                            events.push(Event::ProposeBlock {
-                            new_views: new_views.into_iter().map(|v| v.vote).collect(),
+                                qc: Qc::Aggregated(AggregateQc {
-                            timeout_qc,
+                                    high_qc,
-                        })
+                                    view: msg_view + 1,
-                    }
+                                }),
-                }
+                            });
-            }
-        }
-
-        events
-    }
-}
-
-struct Tally<T: core::hash::Hash + Eq> {
-    cache: HashMap<View, HashSet<T>>,
-    threshold: usize,
-}
-
-impl<T: core::hash::Hash + Eq> Default for Tally<T> {
-    fn default() -> Self {
-        Self::new(0)
-    }
-}
-
-impl<T: core::hash::Hash + Eq> Tally<T> {
-    fn new(threshold: usize) -> Self {
-        Self {
-            cache: Default::default(),
-            threshold,
-        }
-    }
-
-    fn tally(&mut self, view: View, message: T) -> Option<HashSet<T>> {
-        self.tally_by(view, message, self.threshold)
-    }
-
-    fn tally_by(&mut self, view: View, message: T, threshold: usize) -> Option<HashSet<T>> {
-        let entries = self.cache.entry(view).or_default();
-        entries.insert(message);
-        let entries = entries.len();
-        if entries == threshold {
-            Some(self.cache.remove(&view).unwrap())
                         } else {
-            None
+                            events.push(Event::NewView {
+                                timeout_qc,
+                                new_views: votes.into_iter().map(|v| v.vote).collect(),
+                            });
                         }
                     }
+                }
+            }
+        }
+        events
+    }
 }
 
 pub enum Event<Tx: Clone + Hash + Eq> {

simulations/src/node/carnot/mod.rs

@@ -3,6 +3,8 @@
 mod event_builder;
 mod message_cache;
 mod messages;
+mod tally;
+mod timeout;
 
 // std
 use std::hash::Hash;
@@ -22,7 +24,7 @@ use consensus_engine::overlay::RandomBeaconState;
 use consensus_engine::{
     Block, BlockId, Carnot, Committee, Overlay, Payload, Qc, StandardQc, TimeoutQc, View, Vote,
 };
-use nomos_consensus::network::messages::ProposalChunkMsg;
+use nomos_consensus::network::messages::{ProposalChunkMsg, TimeoutQcMsg};
 use nomos_consensus::{
     leader_selection::UpdateableLeaderSelection,
     network::messages::{NewViewMsg, TimeoutMsg, VoteMsg},
@@ -117,6 +119,7 @@ impl<O: Overlay> CarnotNode<O> {
         let overlay = O::new(overlay_settings);
         let engine = Carnot::from_genesis(id, genesis.header().clone(), overlay);
         let state = CarnotState::from(&engine);
+        let timeout = settings.timeout;
         // pk is generated in an insecure way, but for simulation purpouses using a rng like smallrng is more useful
         let mut pk_buff = [0; 32];
         rng.fill_bytes(&mut pk_buff);
@@ -127,7 +130,7 @@ impl<O: Overlay> CarnotNode<O> {
             settings,
             network_interface,
             message_cache: MessageCache::new(),
-            event_builder: event_builder::EventBuilder::new(id),
+            event_builder: event_builder::EventBuilder::new(id, timeout),
             engine,
             random_beacon_pk,
         }
@@ -186,8 +189,14 @@ impl<O: Overlay> CarnotNode<O> {
                     );
                 }
             }
-            Output::BroadcastTimeoutQc { .. } => {
+            Output::BroadcastTimeoutQc { timeout_qc } => {
-                unimplemented!()
+                self.network_interface.send_message(
+                    self.id,
+                    CarnotMessage::TimeoutQc(TimeoutQcMsg {
+                        source: self.id,
+                        qc: timeout_qc,
+                    }),
+                );
             }
             Output::BroadcastProposal { proposal } => {
                 for node in &self.settings.nodes {
@@ -221,7 +230,7 @@ impl<L: UpdateableLeaderSelection, O: Overlay<LeaderSelection = L>> Node for Car
         &self.state
     }
 
-    fn step(&mut self) {
+    fn step(&mut self, elapsed: Duration) {
         // split messages per view, we just one to process the current engine processing view or proposals or timeoutqcs
         let (mut current_view_messages, other_view_messages): (Vec<_>, Vec<_>) = self
             .network_interface
@@ -236,7 +245,9 @@ impl<L: UpdateableLeaderSelection, O: Overlay<LeaderSelection = L>> Node for Car
         self.message_cache.update(other_view_messages);
         current_view_messages.append(&mut self.message_cache.retrieve(self.engine.current_view()));
 
-        let events = self.event_builder.step(current_view_messages, &self.engine);
+        let events = self
+            .event_builder
+            .step(current_view_messages, &self.engine, elapsed);
 
         for event in events {
             let mut output: Vec<Output<CarnotTx>> = vec![];
@@ -313,28 +324,60 @@ impl<L: UpdateableLeaderSelection, O: Overlay<LeaderSelection = L>> Node for Car
                 // This branch means we already get enough new view msgs for this qc
                 // So we can just call approve_new_view
                 Event::NewView {
-                    timeout_qc: _,
+                    timeout_qc,
-                    new_views: _,
+                    new_views,
                 } => {
-                    // let (new, out) = self.engine.approve_new_view(timeout_qc, new_views);
+                    let (new, out) = self.engine.approve_new_view(timeout_qc.clone(), new_views);
-                    // output = Some(out);
+                    output.push(Output::Send(out));
-                    // self.engine = new;
+                    self.engine = new;
-                    // let next_view = timeout_qc.view + 2;
+                    tracing::info!(
-                    // if self.engine.is_leader_for_view(next_view) {
+                        node = parse_idx(&self.id),
-                    //     self.gather_new_views(&[self.id].into_iter().collect(), timeout_qc);
+                        current_view = self.engine.current_view(),
-                    // }
+                        timeout_view = timeout_qc.view,
-                    tracing::error!("unimplemented new view branch");
+                        "receive new view message"
-                    unimplemented!()
+                    );
                 }
                 Event::TimeoutQc { timeout_qc } => {
-                    self.engine = self.engine.receive_timeout_qc(timeout_qc);
+                    tracing::info!(
+                        node = parse_idx(&self.id),
+                        current_view = self.engine.current_view(),
+                        timeout_view = timeout_qc.view,
+                        "receive timeout qc message"
+                    );
+                    self.engine = self.engine.receive_timeout_qc(timeout_qc.clone());
                 }
                 Event::RootTimeout { timeouts } => {
-                    println!("root timeouts: {timeouts:?}");
+                    tracing::debug!("root timeout {:?}", timeouts);
+                    if self.engine.is_member_of_root_committee() {
+                        assert!(timeouts
+                            .iter()
+                            .all(|t| t.view == self.engine.current_view()));
+                        let high_qc = timeouts
+                            .iter()
+                            .map(|t| &t.high_qc)
+                            .chain(std::iter::once(&self.engine.high_qc()))
+                            .max_by_key(|qc| qc.view)
+                            .expect("empty root committee")
+                            .clone();
+                        let timeout_qc = TimeoutQc {
+                            view: timeouts.iter().next().unwrap().view,
+                            high_qc,
+                            sender: self.id(),
+                        };
+                        output.push(Output::BroadcastTimeoutQc { timeout_qc });
+                    }
                 }
                 Event::LocalTimeout => {
-                    tracing::error!("unimplemented local timeout branch");
+                    tracing::info!(
-                    unreachable!("local timeout will never be constructed")
+                        node = parse_idx(&self.id),
+                        current_view = self.engine.current_view(),
+                        "receive local timeout message"
+                    );
+                    let (new, out) = self.engine.local_timeout();
+                    self.engine = new;
+                    if let Some(out) = out {
+                        output.push(Output::Send(out));
+                    }
                 }
                 Event::None => {
                     tracing::error!("unimplemented none branch");

simulations/src/node/carnot/tally.rs

@@ -0,0 +1,37 @@
+use consensus_engine::View;
+use std::collections::{HashMap, HashSet};
+
+pub(crate) struct Tally<T: core::hash::Hash + Eq> {
+    cache: HashMap<View, HashSet<T>>,
+    threshold: usize,
+}
+
+impl<T: core::hash::Hash + Eq> Default for Tally<T> {
+    fn default() -> Self {
+        Self::new(0)
+    }
+}
+
+impl<T: core::hash::Hash + Eq> Tally<T> {
+    pub fn new(threshold: usize) -> Self {
+        Self {
+            cache: Default::default(),
+            threshold,
+        }
+    }
+
+    pub fn tally(&mut self, view: View, message: T) -> Option<HashSet<T>> {
+        self.tally_by(view, message, self.threshold)
+    }
+
+    pub fn tally_by(&mut self, view: View, message: T, threshold: usize) -> Option<HashSet<T>> {
+        let entries = self.cache.entry(view).or_default();
+        entries.insert(message);
+        let entries = entries.len();
+        if entries >= threshold {
+            Some(self.cache.remove(&view).unwrap())
+        } else {
+            None
+        }
+    }
+}

simulations/src/node/carnot/timeout.rs

@@ -0,0 +1,34 @@
+use consensus_engine::View;
+use polars::export::ahash::HashMap;
+use std::time::Duration;
+
+pub(crate) struct TimeoutHandler {
+    pub timeout: Duration,
+    pub per_view: HashMap<View, Duration>,
+}
+
+impl TimeoutHandler {
+    pub fn new(timeout: Duration) -> Self {
+        Self {
+            timeout,
+            per_view: Default::default(),
+        }
+    }
+
+    pub fn step(&mut self, view: View, elapsed: Duration) -> bool {
+        let timeout = self.per_view.entry(view).or_insert(self.timeout);
+        *timeout = timeout.saturating_sub(elapsed);
+        *timeout == Duration::ZERO
+    }
+
+    pub fn is_timeout(&self, view: View) -> bool {
+        self.per_view
+            .get(&view)
+            .map(|t| t.is_zero())
+            .unwrap_or(false)
+    }
+
+    pub fn prune_by_view(&mut self, view: View) {
+        self.per_view.retain(|entry, _| entry > &view);
+    }
+}

simulations/src/node/dummy.rs

@@ -1,5 +1,6 @@
 // std
 use std::collections::{BTreeMap, BTreeSet};
+use std::time::Duration;
 // crates
 use serde::{Deserialize, Serialize};
 // internal
@@ -362,7 +363,7 @@ impl Node for DummyNode {
         &self.state
     }
 
-    fn step(&mut self) {
+    fn step(&mut self, _: Duration) {
         let incoming_messages = self.network_interface.receive_messages();
         self.state.message_count += incoming_messages.len();
 
@@ -565,19 +566,19 @@ mod tests {
         for (_, node) in nodes.iter() {
             assert_eq!(node.current_view(), 0);
         }
-
+        let elapsed = Duration::from_millis(100);
         // 1. Leaders receive vote and broadcast new Proposal(Block) to all nodes.
-        network.dispatch_after(Duration::from_millis(100));
+        network.dispatch_after(elapsed);
         nodes.iter_mut().for_each(|(_, node)| {
-            node.step();
+            node.step(elapsed);
         });
         network.collect_messages();
 
         // 2. a) All nodes received proposal block.
         //    b) Leaf nodes send vote to internal nodes.
-        network.dispatch_after(Duration::from_millis(100));
+        network.dispatch_after(elapsed);
         nodes.iter_mut().for_each(|(_, node)| {
-            node.step();
+            node.step(elapsed);
         });
         network.collect_messages();
 
@@ -598,9 +599,9 @@ mod tests {
         assert!(nodes[&node_id(6)].state().view_state[&1].vote_sent); // Leaf
 
         // 3. Internal nodes send vote to root node.
-        network.dispatch_after(Duration::from_millis(100));
+        network.dispatch_after(elapsed);
         nodes.iter_mut().for_each(|(_, node)| {
-            node.step();
+            node.step(elapsed);
         });
         network.collect_messages();
 
@@ -616,9 +617,9 @@ mod tests {
         assert!(nodes[&node_id(6)].state().view_state[&1].vote_sent); // Leaf
 
         // 4. Root node send vote to next view leader nodes.
-        network.dispatch_after(Duration::from_millis(100));
+        network.dispatch_after(elapsed);
         nodes.iter_mut().for_each(|(_, node)| {
-            node.step();
+            node.step(elapsed);
         });
         network.collect_messages();
 
@@ -632,9 +633,9 @@ mod tests {
         assert!(nodes[&node_id(6)].state().view_state[&1].vote_sent); // Leaf
 
         // 5. Leaders receive vote and broadcast new Proposal(Block) to all nodes.
-        network.dispatch_after(Duration::from_millis(100));
+        network.dispatch_after(elapsed);
         nodes.iter_mut().for_each(|(_, node)| {
-            node.step();
+            node.step(elapsed);
         });
         network.collect_messages();
 
@@ -645,9 +646,9 @@ mod tests {
 
         // 6. a) All nodes received proposal block.
         //    b) Leaf nodes send vote to internal nodes.
-        network.dispatch_after(Duration::from_millis(100));
+        network.dispatch_after(elapsed);
         nodes.iter_mut().for_each(|(_, node)| {
-            node.step();
+            node.step(elapsed);
         });
         network.collect_messages();
 
@@ -705,11 +706,11 @@ mod tests {
         for (_, node) in nodes.iter() {
             assert_eq!(node.current_view(), 0);
         }
-
+        let elapsed = Duration::from_millis(100);
         for _ in 0..7 {
-            network.dispatch_after(Duration::from_millis(100));
+            network.dispatch_after(elapsed);
             nodes.iter_mut().for_each(|(_, node)| {
-                node.step();
+                node.step(elapsed);
             });
             network.collect_messages();
         }
@@ -755,11 +756,11 @@ mod tests {
         for (_, node) in nodes.iter() {
             assert_eq!(node.current_view(), 0);
         }
-
+        let elapsed = Duration::from_millis(100);
         for _ in 0..7 {
-            network.dispatch_after(Duration::from_millis(100));
+            network.dispatch_after(elapsed);
             nodes.iter_mut().for_each(|(_, node)| {
-                node.step();
+                node.step(elapsed);
             });
             network.collect_messages();
         }
@@ -803,10 +804,11 @@ mod tests {
         network.collect_messages();
 
         let nodes = Arc::new(RwLock::new(nodes));
+        let elapsed = Duration::from_millis(100);
         for _ in 0..9 {
-            network.dispatch_after(Duration::from_millis(100));
+            network.dispatch_after(elapsed);
             nodes.write().par_iter_mut().for_each(|(_, node)| {
-                node.step();
+                node.step(elapsed);
             });
             network.collect_messages();
         }

simulations/src/node/dummy_streaming.rs

@@ -1,4 +1,5 @@
 use serde::{Deserialize, Serialize};
+use std::time::Duration;
 
 use super::{Node, NodeId};
 
@@ -42,7 +43,7 @@ impl<S> Node for DummyStreamingNode<S> {
         &self.state
     }
 
-    fn step(&mut self) {
+    fn step(&mut self, _: Duration) {
         self.state.current_view += 1;
     }
 }

simulations/src/node/mod.rs

@@ -154,7 +154,7 @@ pub trait Node {
     // TODO: View must be view whenever we integrate consensus engine
     fn current_view(&self) -> usize;
     fn state(&self) -> &Self::State;
-    fn step(&mut self);
+    fn step(&mut self, elapsed: Duration);
 }
 
 #[cfg(test)]
@@ -174,7 +174,7 @@ impl Node for usize {
         self
     }
 
-    fn step(&mut self) {
+    fn step(&mut self, _: Duration) {
         use std::ops::AddAssign;
         self.add_assign(1);
     }

simulations/src/runner/async_runner.rs

@@ -9,6 +9,7 @@ use rayon::prelude::*;
 use serde::Serialize;
 use std::collections::HashSet;
 use std::sync::Arc;
+use std::time::Duration;
 
 use super::SimulationRunnerHandle;
 
@@ -39,6 +40,7 @@ where
     let (stop_tx, stop_rx) = bounded(1);
     let p = runner.producer.clone();
     let p1 = runner.producer;
+    let elapsed = Duration::from_millis(100);
     let handle = std::thread::spawn(move || {
         loop {
             select! {
@@ -53,7 +55,7 @@ where
                             .write()
                             .par_iter_mut()
                             .filter(|n| ids.contains(&n.id()))
-                            .for_each(N::step);
+                            .for_each(|node|node.step(elapsed));
 
                         p.send(R::try_from(
                             &simulation_state,

simulations/src/runner/glauber_runner.rs

@@ -9,6 +9,7 @@ use rand::prelude::IteratorRandom;
 use serde::Serialize;
 use std::collections::BTreeSet;
 use std::sync::Arc;
+use std::time::Duration;
 
 use super::SimulationRunnerHandle;
 
@@ -42,6 +43,7 @@ where
     let (stop_tx, stop_rx) = bounded(1);
     let p = runner.producer.clone();
     let p1 = runner.producer;
+    let elapsed = Duration::from_millis(100);
     let handle = std::thread::spawn(move || {
         'main: for chunk in iterations.chunks(update_rate) {
             select! {
@@ -61,7 +63,7 @@ where
                             let node: &mut N = shared_nodes
                                 .get_mut(parse_idx(&node_id))
                                 .expect("Node should be present");
-                            node.step();
+                            node.step(elapsed);
                         }
 
                         // check if any condition makes the simulation stop

simulations/src/runner/layered_runner.rs

@@ -33,6 +33,7 @@ use crossbeam::select;
 use std::collections::BTreeSet;
 use std::ops::Not;
 use std::sync::Arc;
+use std::time::Duration;
 // crates
 use fixed_slice_deque::FixedSliceDeque;
 use rand::prelude::{IteratorRandom, SliceRandom};
@@ -80,6 +81,7 @@ where
     let (stop_tx, stop_rx) = bounded(1);
     let p = runner.producer.clone();
     let p1 = runner.producer;
+    let elapsed = Duration::from_millis(100);
     let handle = std::thread::spawn(move || {
         loop {
             select! {
@@ -99,7 +101,7 @@ where
                             .get_mut(parse_idx(&node_id))
                             .expect("Node should be present");
                         let prev_view = node.current_view();
-                        node.step();
+                        node.step(elapsed);
                         let after_view = node.current_view();
                         if after_view > prev_view {
                             // pass node to next step group

simulations/src/runner/mod.rs

@@ -80,15 +80,15 @@ where
             .any(|x| x)
     }
 
-    fn step<N>(&mut self, nodes: &mut [N])
+    fn step<N>(&mut self, nodes: &mut [N], elapsed: Duration)
     where
         N: Node + Send + Sync,
         N::Settings: Clone + Send,
         N::State: Serialize,
     {
-        self.network.dispatch_after(Duration::from_millis(100));
+        self.network.dispatch_after(elapsed);
         nodes.par_iter_mut().for_each(|node| {
-            node.step();
+            node.step(elapsed);
         });
         self.network.collect_messages();
     }

simulations/src/runner/sync_runner.rs

@@ -5,6 +5,7 @@ use crate::warding::SimulationState;
 use crate::{node::Node, output_processors::Record};
 use crossbeam::channel::{bounded, select};
 use std::sync::Arc;
+use std::time::Duration;
 
 /// Simulate with sending the network state to any subscriber
 pub fn simulate<M, N: Node, R>(
@@ -31,6 +32,7 @@ where
     let (stop_tx, stop_rx) = bounded(1);
     let p = runner.producer.clone();
     let p1 = runner.producer;
+    let elapsed = Duration::from_millis(100);
     let handle = std::thread::spawn(move || {
         p.send(R::try_from(&state)?)?;
         loop {
@@ -44,7 +46,7 @@ where
                     // then dead lock will occur
                     {
                         let mut nodes = nodes.write();
-                        inner_runner.step(&mut nodes);
+                        inner_runner.step(&mut nodes, elapsed);
                     }
 
                     p.send(R::try_from(&state)?)?;
@@ -147,7 +149,7 @@ mod tests {
         let mut runner: SimulationRunner<DummyMessage, DummyNode, OutData> =
             SimulationRunner::new(network, nodes, producer, settings).unwrap();
         let mut nodes = runner.nodes.write();
-        runner.inner.step(&mut nodes);
+        runner.inner.step(&mut nodes, Duration::from_millis(100));
         drop(nodes);
 
         let nodes = runner.nodes.read();
@@ -194,7 +196,7 @@ mod tests {
             SimulationRunner::new(network, nodes, Default::default(), settings).unwrap();
 
         let mut nodes = runner.nodes.write();
-        runner.inner.step(&mut nodes);
+        runner.inner.step(&mut nodes, Duration::from_millis(100));
         drop(nodes);
 
         let nodes = runner.nodes.read();