feat: adds host simulation to block build (#167)

# feat: adds host simulation to block build

This PR adds host simulation to the block build loop.

> Note: Requires the signet-sdk release of `0.13.0`​ in order to pass CI.

- bumps bin-base to `0.15.1`​
- deprecates the `BuilderHelper`​ wrapper contract submission in favor of the raw `Zenith`​ contract
- wires up the `HostProvider`​ into the Simulator for host transaction simulation

Author: dylanlott

Cargo.lock

@@ -18,17 +18,17 @@ name = "zenith-builder-example"
 path = "bin/builder.rs"
 
 [dependencies]
-init4-bin-base = { version = "0.13.1", features = ["perms", "aws" ] }
+init4-bin-base = { version = "0.16.0", features = ["perms", "aws"] }
 
-signet-constants = { version = "0.11.2" }
-signet-sim = { version = "0.11.2" }
-signet-tx-cache = { version = "0.11.2" }
-signet-types = { version = "0.11.2" }
-signet-zenith = { version = "0.11.2" }
+signet-constants = { version = "0.13.0" }
+signet-sim = { version = "0.13.0" }
+signet-tx-cache = { version = "0.13.0" }
+signet-types = { version = "0.13.0" }
+signet-zenith = { version = "0.13.0" }
 
-trevm = { version = "0.29.0", features = ["concurrent-db", "test-utils"] }
+trevm = { version = "0.29", features = ["concurrent-db", "test-utils"] }
 
-alloy = { version = "1.0.37", features = [
+alloy = { version = "1.0.35", features = [
     "full",
     "json-rpc",
     "signer-aws",
@@ -39,7 +39,7 @@ alloy = { version = "1.0.37", features = [
     "node-bindings",
     "serde",
     "getrandom",
-    "provider-mev-api"
+    "provider-mev-api",
 ] }
 
 axum = "0.7.5"
@@ -52,3 +52,16 @@ tracing = "0.1.41"
 tokio = { version = "1.36.0", features = ["full", "macros", "rt-multi-thread"] }
 tokio-stream = "0.1.17"
 url = "2.5.4"
+
+# comment / uncomment for local dev
+# [patch.crates-io]
+# signet-constants = { path = "../signet-sdk/crates/constants" }
+# signet-types = { path = "../signet-sdk/crates/types" }
+# signet-zenith = { path = "../signet-sdk/crates/zenith" }
+# signet-sim = { path = "../signet-sdk/crates/sim" }
+# signet-evm = { path = "../signet-sdk/crates/evm" }
+# signet-extract = { path = "../signet-sdk/crates/extract" }
+# signet-journal = { path = "../signet-sdk/crates/journal" }
+# signet-tx-cache = { path = "../signet-sdk/crates/tx-cache" }
+# signet-bundle = { path = "../signet-sdk/crates/bundle" }
+# init4-bin-base = { path = "../bin-base" }

Cargo.toml

@@ -44,9 +44,8 @@ async fn main() -> eyre::Result<()> {
     let (submit_channel, submit_jh) = submit.spawn();
 
     // Set up the simulator
-    let sim = Simulator::new(&config, ru_provider.clone(), block_env);
-    let build_jh =
-        sim.spawn_simulator_task(config.constants.clone(), cache_system.sim_cache, submit_channel);
+    let sim = Simulator::new(&config, host_provider, ru_provider, block_env);
+    let build_jh = sim.spawn_simulator_task(cache_system.sim_cache, submit_channel);
 
     // Start the healthcheck server
     let server = serve_builder(([0, 0, 0, 0], config.builder_port));

bin/builder.rs

@@ -1,4 +1,4 @@
-use crate::{quincey::Quincey, tasks::block::cfg::SignetCfgEnv};
+use crate::quincey::Quincey;
 use alloy::{
     network::{Ethereum, EthereumWallet},
     primitives::Address,
@@ -66,14 +66,6 @@ pub const DEFAULT_CONCURRENCY_LIMIT: usize = 8;
 /// chain.
 #[derive(Debug, Clone, FromEnv)]
 pub struct BuilderConfig {
-    /// The chain ID of the host chain.
-    #[from_env(var = "HOST_CHAIN_ID", desc = "The chain ID of the host chain")]
-    pub host_chain_id: u64,
-
-    /// The chain ID of the rollup chain.
-    #[from_env(var = "RU_CHAIN_ID", desc = "The chain ID of the rollup chain")]
-    pub ru_chain_id: u64,
-
     /// URL for Host RPC node.
     #[from_env(
         var = "HOST_RPC_URL",
@@ -101,17 +93,6 @@ pub struct BuilderConfig {
     )]
     pub flashbots_endpoint: Option<url::Url>,
 
-    /// Address of the Zenith contract on Host.
-    #[from_env(var = "ZENITH_ADDRESS", desc = "address of the Zenith contract on Host")]
-    pub zenith_address: Address,
-
-    /// Address of the Builder Helper contract on Host.
-    #[from_env(
-        var = "BUILDER_HELPER_ADDRESS",
-        desc = "address of the Builder Helper contract on Host"
-    )]
-    pub builder_helper_address: Address,
-
     /// URL for remote Quincey Sequencer server to sign blocks.
     /// NB: Disregarded if a sequencer_signer is configured.
     #[from_env(
@@ -165,10 +146,18 @@ pub struct BuilderConfig {
     )]
     pub concurrency_limit: Option<usize>,
 
+    /// Optional maximum host gas coefficient to use when building blocks.
+    /// Defaults to 80% (80) if not set.
+    #[from_env(
+        var = "MAX_HOST_GAS_COEFFICIENT",
+        desc = "Optional maximum host gas coefficient, as a percentage, to use when building blocks",
+        default = 80
+    )]
+    pub max_host_gas_coefficient: Option<u8>,
+
     /// The slot calculator for the builder.
     pub slot_calculator: SlotCalculator,
 
-    // TODO: Make this compatible with FromEnv again, somehow it broke
     /// The signet system constants.
     pub constants: SignetSystemConstants,
 }
@@ -179,7 +168,7 @@ impl BuilderConfig {
         static ONCE: tokio::sync::OnceCell<LocalOrAws> = tokio::sync::OnceCell::const_new();
 
         ONCE.get_or_try_init(|| async {
-            LocalOrAws::load(&self.builder_key, Some(self.host_chain_id)).await
+            LocalOrAws::load(&self.builder_key, Some(self.constants.host_chain_id())).await
         })
         .await
         .cloned()
@@ -189,7 +178,7 @@ impl BuilderConfig {
     /// Connect to the Sequencer signer.
     pub async fn connect_sequencer_signer(&self) -> eyre::Result<Option<LocalOrAws>> {
         if let Some(sequencer_key) = &self.sequencer_key {
-            LocalOrAws::load(sequencer_key, Some(self.host_chain_id))
+            LocalOrAws::load(sequencer_key, Some(self.constants.host_chain_id()))
                 .await
                 .map_err(Into::into)
                 .map(Some)
@@ -240,7 +229,7 @@ impl BuilderConfig {
 
     /// Connect to the Zenith instance, using the specified provider.
     pub const fn connect_zenith(&self, provider: HostProvider) -> ZenithInstance {
-        Zenith::new(self.zenith_address, provider)
+        Zenith::new(self.constants.host_zenith(), provider)
     }
 
     /// Get an oauth2 token for the builder, starting the authenticator if it
@@ -270,11 +259,6 @@ impl BuilderConfig {
         Ok(Quincey::new_remote(client, url, token))
     }
 
-    /// Create a [`SignetCfgEnv`] using this config.
-    pub const fn cfg_env(&self) -> SignetCfgEnv {
-        SignetCfgEnv { chain_id: self.ru_chain_id }
-    }
-
     /// Memoizes the concurrency limit for the current system. Uses [`std::thread::available_parallelism`] if no
     /// value is set. If that for some reason fails, it returns the default concurrency limit.
     pub fn concurrency_limit(&self) -> usize {
@@ -292,4 +276,11 @@ impl BuilderConfig {
                 .unwrap_or(DEFAULT_CONCURRENCY_LIMIT)
         })
     }
+
+    /// Returns the maximum host gas to use for block building based on the configured max host gas coefficient.
+    pub fn max_host_gas(&self, gas_limit: u64) -> u64 {
+        // Set max host gas to a percentage of the host block gas limit
+        ((gas_limit as u128 * (self.max_host_gas_coefficient.unwrap_or(80) as u128)) / 100u128)
+            as u64
+    }
 }

src/config.rs

@@ -2,10 +2,10 @@
 //! actor that handles the simulation of a stream of bundles and transactions
 //! and turns them into valid Pecorino blocks for network submission.
 use crate::{
-    config::{BuilderConfig, RuProvider},
+    config::{BuilderConfig, HostProvider, RuProvider},
     tasks::env::SimEnv,
 };
-use alloy::{eips::BlockId, network::Ethereum};
+use alloy::consensus::Header;
 use init4_bin_base::{
     deps::metrics::{counter, histogram},
     utils::calc::SlotCalculator,
@@ -21,13 +21,6 @@ use tokio::{
     task::JoinHandle,
 };
 use tracing::{Instrument, Span, debug, instrument};
-use trevm::revm::{
-    context::BlockEnv,
-    database::{AlloyDB, WrapDatabaseAsync},
-    inspector::NoOpInspector,
-};
-
-type AlloyDatabaseProvider = WrapDatabaseAsync<AlloyDB<Ethereum, RuProvider>>;
 
 /// `Simulator` is responsible for periodically building blocks and submitting them for
 /// signing and inclusion in the blockchain. It wraps a rollup provider and a slot
@@ -36,6 +29,8 @@ type AlloyDatabaseProvider = WrapDatabaseAsync<AlloyDB<Ethereum, RuProvider>>;
 pub struct Simulator {
     /// Configuration for the builder.
     pub config: BuilderConfig,
+    /// Host Provider to interact with the host chain.
+    pub host_provider: HostProvider,
     /// A provider that cannot sign transactions, used for interacting with the rollup.
     pub ru_provider: RuProvider,
     /// The block configuration environment on which to simulate
@@ -52,8 +47,18 @@ pub struct SimResult {
 }
 
 impl SimResult {
+    /// Get a reference to the previous host header.
+    pub const fn prev_host(&self) -> &Header {
+        self.sim_env.prev_host()
+    }
+
+    /// Get a reference to the previous rollup header.
+    pub const fn prev_rollup(&self) -> &Header {
+        self.sim_env.prev_rollup()
+    }
+
     /// Returns the block number of the built block.
-    pub const fn block_number(&self) -> u64 {
+    pub const fn rollup_block_number(&self) -> u64 {
         self.block.block_number()
     }
 
@@ -88,17 +93,23 @@ impl Simulator {
     /// A new `Simulator` instance.
     pub fn new(
         config: &BuilderConfig,
+        host_provider: HostProvider,
         ru_provider: RuProvider,
         sim_env: watch::Receiver<Option<SimEnv>>,
     ) -> Self {
-        Self { config: config.clone(), ru_provider, sim_env }
+        Self { config: config.clone(), host_provider, ru_provider, sim_env }
     }
 
     /// Get the slot calculator.
     pub const fn slot_calculator(&self) -> &SlotCalculator {
         &self.config.slot_calculator
     }
 
+    /// Get the system constants.
+    pub const fn constants(&self) -> &SignetSystemConstants {
+        &self.config.constants
+    }
+
     /// Handles building a single block.
     ///
     /// Builds a block in the block environment with items from the simulation cache
@@ -121,25 +132,24 @@ impl Simulator {
     ))]
     pub async fn handle_build(
         &self,
-        constants: SignetSystemConstants,
         sim_items: SimCache,
         finish_by: Instant,
-        block_env: BlockEnv,
+        sim_env: &SimEnv,
     ) -> eyre::Result<BuiltBlock> {
         let concurrency_limit = self.config.concurrency_limit();
 
-        // NB: Build AlloyDB from the previous block number's state, since block_env maps to the in-progress block
-        let db = self.create_db(block_env.number.to::<u64>() - 1).unwrap();
+        let rollup_env = sim_env.sim_rollup_env(self.constants(), self.ru_provider.clone());
 
-        let block_build: BlockBuild<_, NoOpInspector> = BlockBuild::new(
-            db,
-            constants,
-            self.config.cfg_env(),
-            block_env,
+        let host_env = sim_env.sim_host_env(self.constants(), self.host_provider.clone());
+
+        let block_build = BlockBuild::new(
+            rollup_env,
+            host_env,
             finish_by,
             concurrency_limit,
             sim_items,
             self.config.rollup_block_gas_limit,
+            self.config.max_host_gas(sim_env.prev_host().gas_limit),
         );
 
         let built_block = block_build.build().in_current_span().await;
@@ -149,7 +159,7 @@ impl Simulator {
             "block simulation completed",
         );
         counter!("signet.builder.built_blocks").increment(1);
-        histogram!("signet.builder.built_blocks.tx_count").record(built_block.tx_count() as f64);
+        histogram!("signet.builder.built_blocks.tx_count").record(built_block.tx_count() as u32);
 
         Ok(built_block)
     }
@@ -168,13 +178,12 @@ impl Simulator {
     /// A `JoinHandle` for the spawned task.
     pub fn spawn_simulator_task(
         self,
-        constants: SignetSystemConstants,
         cache: SimCache,
         submit_sender: mpsc::UnboundedSender<SimResult>,
     ) -> JoinHandle<()> {
         debug!("starting simulator task");
 
-        tokio::spawn(async move { self.run_simulator(constants, cache, submit_sender).await })
+        tokio::spawn(async move { self.run_simulator(cache, submit_sender).await })
     }
 
     /// This function runs indefinitely, waiting for the block environment to be set and checking
@@ -195,7 +204,6 @@ impl Simulator {
     /// - `submit_sender`: A channel sender used to submit built blocks.
     async fn run_simulator(
         mut self,
-        constants: SignetSystemConstants,
         cache: SimCache,
         submit_sender: mpsc::UnboundedSender<SimResult>,
     ) {
@@ -217,7 +225,7 @@ impl Simulator {
             let sim_cache = cache.clone();
 
             let Ok(block) = self
-                .handle_build(constants.clone(), sim_cache, finish_by, sim_env.block_env.clone())
+                .handle_build(sim_cache, finish_by, &sim_env)
                 .instrument(span.clone())
                 .await
                 .inspect_err(|err| span_error!(span, %err, "error during block build"))
@@ -250,22 +258,4 @@ impl Simulator {
         let deadline = Instant::now() + Duration::from_secs(remaining);
         deadline.max(Instant::now())
     }
-
-    /// Creates an `AlloyDB` instance from the rollup provider.
-    ///
-    /// # Returns
-    ///
-    /// An `Option` containing the wrapped database or `None` if an error occurs.
-    fn create_db(&self, latest_block_number: u64) -> Option<AlloyDatabaseProvider> {
-        // Make an AlloyDB instance from the rollup provider with that latest block number
-        let alloy_db: AlloyDB<Ethereum, RuProvider> =
-            AlloyDB::new(self.ru_provider.clone(), BlockId::from(latest_block_number));
-
-        // Wrap the AlloyDB instance in a WrapDatabaseAsync and return it.
-        // This is safe to unwrap because the main function sets the proper runtime settings.
-        //
-        // See: https://docs.rs/tokio/latest/tokio/attr.main.html
-        let wrapped_db: AlloyDatabaseProvider = WrapDatabaseAsync::new(alloy_db).unwrap();
-        Some(wrapped_db)
-    }
 }

src/tasks/block/sim.rs

@@ -16,7 +16,7 @@ use tracing::{debug, info};
 #[derive(Debug)]
 pub struct CacheTask {
     /// The channel to receive the block environment.
-    env: watch::Receiver<Option<SimEnv>>,
+    envs: watch::Receiver<Option<SimEnv>>,
     /// The channel to receive the transaction bundles.
     bundles: mpsc::UnboundedReceiver<TxCacheBundle>,
     /// The channel to receive the transactions.
@@ -30,24 +30,27 @@ impl CacheTask {
         bundles: mpsc::UnboundedReceiver<TxCacheBundle>,
         txns: mpsc::UnboundedReceiver<TxEnvelope>,
     ) -> Self {
-        Self { env, bundles, txns }
+        Self { envs: env, bundles, txns }
     }
 
     async fn task_future(mut self, cache: SimCache) {
         loop {
             let mut basefee = 0;
             tokio::select! {
                 biased;
-                res = self.env.changed() => {
+                res = self.envs.changed() => {
                     if res.is_err() {
                         debug!("Cache task: env channel closed, exiting");
                         break;
                     }
-                    if let Some(env) = self.env.borrow_and_update().as_ref() {
-                        basefee = env.block_env.basefee;
-                        info!(basefee, block_env_number = env.block_env.number.to::<u64>(), block_env_timestamp = env.block_env.timestamp.to::<u64>(), "rollup block env changed, clearing cache");
+
+                    if let Some(env) = self.envs.borrow_and_update().as_ref() {
+                        let sim_env = env.rollup_env();
+
+                        basefee = sim_env.basefee;
+                        info!(basefee, block_env_number = sim_env.number.to::<u64>(), block_env_timestamp = sim_env.timestamp.to::<u64>(), "rollup block env changed, clearing cache");
                         cache.clean(
-                            env.block_env.number.to(), env.block_env.timestamp.to()
+                            sim_env.number.to(), sim_env.timestamp.to()
                         );
                     }
                 }