initial types

crates/engine/tree/Cargo.toml

@@ -65,6 +65,7 @@ rayon.workspace = true
 tracing.workspace = true
 derive_more.workspace = true
 parking_lot.workspace = true
+crossbeam-channel.workspace = true
 
 # optional deps for test-utils
 reth-prune-types = { workspace = true, optional = true }

crates/engine/tree/src/tree/payload_processor/mod.rs

@@ -40,15 +40,13 @@ use reth_trie_sparse::{
     ClearedSparseStateTrie, SparseStateTrie, SparseTrie,
 };
 use reth_trie_sparse_parallel::{ParallelSparseTrie, ParallelismThresholds};
-use std::{
-    sync::{
-        atomic::AtomicBool,
-        mpsc::{self, channel, Sender},
-        Arc,
-    },
-    time::Instant,
+use std::sync::{
+    atomic::AtomicBool,
+    mpsc::{self, channel},
+    Arc,
 };
-use tracing::{debug, debug_span, instrument, warn};
+use crossbeam_channel::Sender as CrossbeamSender;
+use tracing::{debug, instrument, warn};
 
 mod configured_sparse_trie;
 pub mod executor;
@@ -322,7 +320,7 @@ where
         mut transactions: mpsc::Receiver<impl ExecutableTxFor<Evm> + Clone + Send + 'static>,
         transaction_count_hint: usize,
         provider_builder: StateProviderBuilder<N, P>,
-        to_multi_proof: Option<Sender<MultiProofMessage>>,
+        to_multi_proof: Option<CrossbeamSender<MultiProofMessage>>,
     ) -> CacheTaskHandle
     where
         P: BlockReader + StateProviderFactory + StateReader + Clone + 'static,
@@ -452,7 +450,7 @@ where
 #[derive(Debug)]
 pub struct PayloadHandle<Tx, Err> {
     /// Channel for evm state updates
-    to_multi_proof: Option<Sender<MultiProofMessage>>,
+    to_multi_proof: Option<CrossbeamSender<MultiProofMessage>>,
     // must include the receiver of the state root wired to the sparse trie
     prewarm_handle: CacheTaskHandle,
     /// Receiver for the state root
@@ -530,7 +528,7 @@ pub(crate) struct CacheTaskHandle {
     /// Metrics for the caches
     cache_metrics: CachedStateMetrics,
     /// Channel to the spawned prewarm task if any
-    to_prewarm_task: Option<Sender<PrewarmTaskEvent>>,
+    to_prewarm_task: Option<std::sync::mpsc::Sender<PrewarmTaskEvent>>,
 }
 
 impl CacheTaskHandle {

crates/engine/tree/src/tree/payload_processor/prewarm.rs

@@ -39,7 +39,8 @@ use std::{
     },
     time::Instant,
 };
-use tracing::{debug, debug_span, instrument, trace, warn};
+use crossbeam_channel::Sender as CrossbeamSender;
+use tracing::{debug, trace, warn};
 
 /// A wrapper for transactions that includes their index in the block.
 #[derive(Clone)]
@@ -83,7 +84,7 @@ where
     /// The number of transactions to be processed
     transaction_count_hint: usize,
     /// Sender to emit evm state outcome messages, if any.
-    to_multi_proof: Option<Sender<MultiProofMessage>>,
+    to_multi_proof: Option<CrossbeamSender<MultiProofMessage>>,
     /// Receiver for events produced by tx execution
     actions_rx: Receiver<PrewarmTaskEvent>,
 }
@@ -99,7 +100,7 @@ where
         executor: WorkloadExecutor,
         execution_cache: PayloadExecutionCache,
         ctx: PrewarmContext<N, P, Evm>,
-        to_multi_proof: Option<Sender<MultiProofMessage>>,
+        to_multi_proof: Option<CrossbeamSender<MultiProofMessage>>,
         transaction_count_hint: usize,
         max_concurrency: usize,
     ) -> (Self, Sender<PrewarmTaskEvent>) {

crates/trie/parallel/src/proof_task.rs

@@ -68,6 +68,26 @@ type TrieNodeProviderResult = Result<Option<RevealedNode>, SparseTrieError>;
 type AccountMultiproofResult =
     Result<(DecodedMultiProof, ParallelTrieStats), ParallelStateRootError>;
 
+/// Message containing a completed proof result with metadata for direct delivery to `MultiProofTask`.
+///
+/// This type enables workers to send proof results directly to the `MultiProofTask` event loop.
+#[derive(Debug)]
+pub struct ProofResultMessage {
+    /// Sequence number for ordering proofs
+    pub sequence_number: u64,
+    /// The proof calculation result
+    pub result: AccountMultiproofResult,
+    /// Time taken for the entire proof calculation (from dispatch to completion)
+    pub elapsed: Duration,
+    /// Original state update that triggered this proof
+    pub state: HashedPostState,
+}
+
+/// Type alias for the proof result sender channel.
+///
+/// Workers use this sender to deliver proof results directly to `MultiProofTask`.
+pub type ProofResultSender = CrossbeamSender<ProofResultMessage>;
+
 /// Internal message for storage workers.
 #[derive(Debug)]
 enum StorageWorkerJob {