perf: optimize txpool_status RPC by avoiding full transaction collection (#17392)

Co-authored-by: Matthias Seitz <matthias.seitz@outlook.de>

crates/rpc/rpc/src/txpool.rs

@@ -88,8 +88,8 @@ where
     /// Handler for `txpool_status`
     async fn txpool_status(&self) -> RpcResult<TxpoolStatus> {
         trace!(target: "rpc::eth", "Serving txpool_status");
-        let all = self.pool.all_transactions();
-        Ok(TxpoolStatus { pending: all.pending.len() as u64, queued: all.queued.len() as u64 })
+        let (pending, queued) = self.pool.pending_and_queued_txn_count();
+        Ok(TxpoolStatus { pending: pending as u64, queued: queued as u64 })
     }
 
     /// Returns a summary of all the transactions currently pending for inclusion in the next

crates/transaction-pool/src/lib.rs

@@ -591,6 +591,13 @@ where
         self.pool.queued_transactions()
     }
 
+    fn pending_and_queued_txn_count(&self) -> (usize, usize) {
+        let data = self.pool.get_pool_data();
+        let pending = data.pending_transactions_count();
+        let queued = data.queued_transactions_count();
+        (pending, queued)
+    }
+
     fn all_transactions(&self) -> AllPoolTransactions<Self::Transaction> {
         self.pool.all_transactions()
     }

crates/transaction-pool/src/noop.rs

@@ -190,6 +190,10 @@ impl<T: EthPoolTransaction> TransactionPool for NoopTransactionPool<T> {
         vec![]
     }
 
+    fn pending_and_queued_txn_count(&self) -> (usize, usize) {
+        (0, 0)
+    }
+
     fn all_transactions(&self) -> AllPoolTransactions<Self::Transaction> {
         AllPoolTransactions::default()
     }

crates/transaction-pool/src/pool/parked.rs

@@ -131,7 +131,7 @@ impl<T: ParkedOrd> ParkedPool<T> {
     /// Returns an iterator over all transactions in the pool
     pub(crate) fn all(
         &self,
-    ) -> impl Iterator<Item = Arc<ValidPoolTransaction<T::Transaction>>> + '_ {
+    ) -> impl ExactSizeIterator<Item = Arc<ValidPoolTransaction<T::Transaction>>> + '_ {
         self.by_id.values().map(|tx| tx.transaction.clone().into())
     }
 

crates/transaction-pool/src/pool/pending.rs

@@ -158,7 +158,7 @@ impl<T: TransactionOrdering> PendingPool<T> {
     /// Returns an iterator over all transactions in the pool
     pub(crate) fn all(
         &self,
-    ) -> impl Iterator<Item = Arc<ValidPoolTransaction<T::Transaction>>> + '_ {
+    ) -> impl ExactSizeIterator<Item = Arc<ValidPoolTransaction<T::Transaction>>> + '_ {
         self.by_id.values().map(|tx| tx.transaction.clone())
     }
 

crates/transaction-pool/src/pool/txpool.rs

@@ -434,6 +434,11 @@ impl<T: TransactionOrdering> TxPool<T> {
         self.pending_pool.all()
     }
 
+    /// Returns the number of transactions from the pending sub-pool
+    pub(crate) fn pending_transactions_count(&self) -> usize {
+        self.pending_pool.len()
+    }
+
     /// Returns all pending transactions filtered by predicate
     pub(crate) fn pending_transactions_with_predicate(
         &self,
@@ -462,6 +467,11 @@ impl<T: TransactionOrdering> TxPool<T> {
         self.basefee_pool.all().chain(self.queued_pool.all())
     }
 
+    /// Returns the number of transactions in parked pools
+    pub(crate) fn queued_transactions_count(&self) -> usize {
+        self.basefee_pool.len() + self.queued_pool.len()
+    }
+
     /// Returns queued and pending transactions for the specified sender
     pub fn queued_and_pending_txs_by_sender(
         &self,

crates/transaction-pool/src/traits.rs

@@ -355,6 +355,10 @@ pub trait TransactionPool: Clone + Debug + Send + Sync {
     /// Consumer: RPC
     fn queued_transactions(&self) -> Vec<Arc<ValidPoolTransaction<Self::Transaction>>>;
 
+    /// Returns the number of transactions that are ready for inclusion in the next block and the
+    /// number of transactions that are ready for inclusion in future blocks: `(pending, queued)`.
+    fn pending_and_queued_txn_count(&self) -> (usize, usize);
+
     /// Returns all transactions that are currently in the pool grouped by whether they are ready
     /// for inclusion in the next block or not.
     ///