feat: add BestTransactionsWithAttributes blob fee checks (#6674)

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

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

@@ -17,13 +17,14 @@ use tracing::debug;
 ///
 /// This is a wrapper around [`BestTransactions`] that also enforces a specific basefee.
 ///
-/// This iterator guarantees that all transaction it returns satisfy the base fee.
-pub(crate) struct BestTransactionsWithBasefee<T: TransactionOrdering> {
+/// This iterator guarantees that all transaction it returns satisfy both the base fee and blob fee!
+pub(crate) struct BestTransactionsWithFees<T: TransactionOrdering> {
     pub(crate) best: BestTransactions<T>,
     pub(crate) base_fee: u64,
+    pub(crate) base_fee_per_blob_gas: u64,
 }
 
-impl<T: TransactionOrdering> crate::traits::BestTransactions for BestTransactionsWithBasefee<T> {
+impl<T: TransactionOrdering> crate::traits::BestTransactions for BestTransactionsWithFees<T> {
     fn mark_invalid(&mut self, tx: &Self::Item) {
         BestTransactions::mark_invalid(&mut self.best, tx)
     }
@@ -41,7 +42,7 @@ impl<T: TransactionOrdering> crate::traits::BestTransactions for BestTransaction
     }
 }
 
-impl<T: TransactionOrdering> Iterator for BestTransactionsWithBasefee<T> {
+impl<T: TransactionOrdering> Iterator for BestTransactionsWithFees<T> {
     type Item = Arc<ValidPoolTransaction<T::Transaction>>;
 
     fn next(&mut self) -> Option<Self::Item> {
@@ -52,6 +53,13 @@ impl<T: TransactionOrdering> Iterator for BestTransactionsWithBasefee<T> {
                 // tx violates base fee, mark it as invalid and continue
                 crate::traits::BestTransactions::mark_invalid(self, &best);
             } else {
+                // tx is EIP4844 and violates blob fee, mark it as invalid and continue
+                if best.transaction.max_fee_per_blob_gas().is_some_and(|max_fee_per_blob_gas| {
+                    max_fee_per_blob_gas < self.base_fee_per_blob_gas as u128
+                }) {
+                    crate::traits::BestTransactions::mark_invalid(self, &best);
+                    continue;
+                };
                 return Some(best)
             }
         }

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

@@ -80,12 +80,42 @@ impl<T: PoolTransaction> BlobTransactions<T> {
         Some(tx.transaction)
     }
 
-    /// Returns all transactions that satisfy the given basefee and blob_fee.
-    pub(crate) const fn satisfy_attributes(
+    /// Returns all transactions that satisfy the given basefee and blobfee.
+    ///
+    /// Note: This does not remove any the transactions from the pool.
+    pub(crate) fn satisfy_attributes(
         &self,
-        _best_transactions_attributes: BestTransactionsAttributes,
+        best_transactions_attributes: BestTransactionsAttributes,
     ) -> Vec<Arc<ValidPoolTransaction<T>>> {
-        Vec::new()
+        let mut transactions = Vec::new();
+        {
+            // short path if blob_fee is None in provided best transactions attributes
+            if let Some(blob_fee_to_satisfy) =
+                best_transactions_attributes.blob_fee.map(|fee| fee as u128)
+            {
+                let mut iter = self.by_id.iter().peekable();
+
+                while let Some((id, tx)) = iter.next() {
+                    if tx.transaction.max_fee_per_blob_gas().unwrap_or_default() <
+                        blob_fee_to_satisfy ||
+                        tx.transaction.max_fee_per_gas() <
+                            best_transactions_attributes.basefee as u128
+                    {
+                        // does not satisfy the blob fee or base fee
+                        // still parked in blob pool -> skip descendant transactions
+                        'this: while let Some((peek, _)) = iter.peek() {
+                            if peek.sender != id.sender {
+                                break 'this
+                            }
+                            iter.next();
+                        }
+                    } else {
+                        transactions.push(tx.transaction.clone());
+                    }
+                }
+            }
+        }
+        transactions
     }
 
     /// Returns true if the pool exceeds the given limit

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

@@ -1,7 +1,7 @@
 use crate::{
     identifier::{SenderId, TransactionId},
     pool::{
-        best::{BestTransactions, BestTransactionsWithBasefee},
+        best::{BestTransactions, BestTransactionsWithFees},
         size::SizeTracker,
     },
     Priority, SubPoolLimit, TransactionOrdering, ValidPoolTransaction,
@@ -115,9 +115,13 @@ impl<T: TransactionOrdering> PendingPool<T> {
         }
     }
 
-    /// Same as `best` but only returns transactions that satisfy the given basefee.
-    pub(crate) fn best_with_basefee(&self, base_fee: u64) -> BestTransactionsWithBasefee<T> {
-        BestTransactionsWithBasefee { best: self.best(), base_fee }
+    /// Same as `best` but only returns transactions that satisfy the given basefee and blobfee.
+    pub(crate) fn best_with_basefee_and_blobfee(
+        &self,
+        base_fee: u64,
+        base_fee_per_blob_gas: u64,
+    ) -> BestTransactionsWithFees<T> {
+        BestTransactionsWithFees { best: self.best(), base_fee, base_fee_per_blob_gas }
     }
 
     /// Same as `best` but also includes the given unlocked transactions.

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

@@ -287,38 +287,67 @@ impl<T: TransactionOrdering> TxPool<T> {
         }
     }
 
-    /// Returns an iterator that yields transactions that are ready to be included in the block.
+    /// Returns an iterator that yields transactions that are ready to be included in the block with
+    /// the tracked fees.
     pub(crate) fn best_transactions(&self) -> BestTransactions<T> {
         self.pending_pool.best()
     }
 
     /// Returns an iterator that yields transactions that are ready to be included in the block with
     /// the given base fee and optional blob fee.
+    ///
+    /// If the provided attributes differ from the currently tracked fees, this will also include
+    /// transactions that are unlocked by the new fees, or exclude transactions that are no longer
+    /// valid with the new fees.
     pub(crate) fn best_transactions_with_attributes(
         &self,
         best_transactions_attributes: BestTransactionsAttributes,
     ) -> Box<dyn crate::traits::BestTransactions<Item = Arc<ValidPoolTransaction<T::Transaction>>>>
     {
+        // First we need to check if the given base fee is different than what's currently being
+        // tracked
         match best_transactions_attributes.basefee.cmp(&self.all_transactions.pending_fees.base_fee)
         {
             Ordering::Equal => {
-                // fee unchanged, nothing to shift
-                Box::new(self.best_transactions())
+                // for EIP-4844 transactions we also need to check if the blob fee is now lower than
+                // what's currently being tracked, if so we need to include transactions from the
+                // blob pool that are valid with the lower blob fee
+                if best_transactions_attributes
+                    .blob_fee
+                    .map_or(false, |fee| fee < self.all_transactions.pending_fees.blob_fee as u64)
+                {
+                    let unlocked_by_blob_fee =
+                        self.blob_pool.satisfy_attributes(best_transactions_attributes);
+
+                    Box::new(self.pending_pool.best_with_unlocked(
+                        unlocked_by_blob_fee,
+                        self.all_transactions.pending_fees.base_fee,
+                    ))
+                } else {
+                    Box::new(self.pending_pool.best())
+                }
             }
             Ordering::Greater => {
                 // base fee increased, we only need to enforce this on the pending pool
-                Box::new(self.pending_pool.best_with_basefee(best_transactions_attributes.basefee))
+                Box::new(self.pending_pool.best_with_basefee_and_blobfee(
+                    best_transactions_attributes.basefee,
+                    best_transactions_attributes.blob_fee.unwrap_or_default(),
+                ))
             }
             Ordering::Less => {
-                // base fee decreased, we need to move transactions from the basefee pool to the
-                // pending pool and satisfy blob fee transactions as well
-                let unlocked_with_blob =
-                    self.blob_pool.satisfy_attributes(best_transactions_attributes);
+                // base fee decreased, we need to move transactions from the basefee + blob pool to
+                // the pending pool that might be unlocked by the lower base fee
+                let mut unlocked = self
+                    .basefee_pool
+                    .satisfy_base_fee_transactions(best_transactions_attributes.basefee);
 
-                Box::new(self.pending_pool.best_with_unlocked(
-                    unlocked_with_blob,
-                    self.all_transactions.pending_fees.base_fee,
-                ))
+                // also include blob pool transactions that are now unlocked
+                unlocked.extend(self.blob_pool.satisfy_attributes(best_transactions_attributes));
+
+                Box::new(
+                    self.pending_pool
+                        .best_with_unlocked(unlocked, self.all_transactions.pending_fees.base_fee),
+                )
             }
         }
     }