fix(api): Use better gas per pubdata in API (pure server changes) (#1311

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core/lib/multivm/src/utils.rs

@@ -77,38 +77,61 @@ pub fn get_batch_base_fee(l1_batch_env: &L1BatchEnv, vm_version: VmVersion) -> u
 pub fn adjust_pubdata_price_for_tx(
     batch_fee_input: BatchFeeInput,
     tx_gas_per_pubdata_limit: U256,
+    max_base_fee: Option<U256>,
     vm_version: VmVersion,
 ) -> BatchFeeInput {
-    if U256::from(derive_base_fee_and_gas_per_pubdata(batch_fee_input, vm_version).1)
-        <= tx_gas_per_pubdata_limit
+    // If no max base fee was provided, we just use the maximal one for convenience.
+    let max_base_fee = max_base_fee.unwrap_or(U256::MAX);
+    let desired_gas_per_pubdata =
+        tx_gas_per_pubdata_limit.min(get_max_gas_per_pubdata_byte(vm_version).into());
+
+    let (current_base_fee, current_gas_per_pubdata) =
+        derive_base_fee_and_gas_per_pubdata(batch_fee_input, vm_version);
+
+    if U256::from(current_gas_per_pubdata) <= desired_gas_per_pubdata
+        && U256::from(current_base_fee) <= max_base_fee
     {
         // gas per pubdata is already smaller than or equal to `tx_gas_per_pubdata_limit`.
         return batch_fee_input;
     }
 
     match batch_fee_input {
         BatchFeeInput::L1Pegged(fee_input) => {
+            let current_l2_fair_gas_price = U256::from(fee_input.fair_l2_gas_price);
+            let fair_l2_gas_price = if max_base_fee < current_l2_fair_gas_price {
+                max_base_fee
+            } else {
+                current_l2_fair_gas_price
+            };
+
             // `gasPerPubdata = ceil(17 * l1gasprice / fair_l2_gas_price)`
             // `gasPerPubdata <= 17 * l1gasprice / fair_l2_gas_price + 1`
             // `fair_l2_gas_price(gasPerPubdata - 1) / 17 <= l1gasprice`
-            let new_l1_gas_price = U256::from(fee_input.fair_l2_gas_price)
-                * (tx_gas_per_pubdata_limit - U256::from(1u32))
-                / U256::from(17);
+            let new_l1_gas_price =
+                fair_l2_gas_price * (desired_gas_per_pubdata - U256::from(1u32)) / U256::from(17);
 
             BatchFeeInput::L1Pegged(L1PeggedBatchFeeModelInput {
                 l1_gas_price: new_l1_gas_price.as_u64(),
-                ..fee_input
+                fair_l2_gas_price: fair_l2_gas_price.as_u64(),
             })
         }
         BatchFeeInput::PubdataIndependent(fee_input) => {
+            let current_l2_fair_gas_price = U256::from(fee_input.fair_l2_gas_price);
+            let fair_l2_gas_price = if max_base_fee < current_l2_fair_gas_price {
+                max_base_fee
+            } else {
+                current_l2_fair_gas_price
+            };
+
             // `gasPerPubdata = ceil(fair_pubdata_price / fair_l2_gas_price)`
             // `gasPerPubdata <= fair_pubdata_price / fair_l2_gas_price + 1`
             // `fair_l2_gas_price(gasPerPubdata - 1) <= fair_pubdata_price`
-            let new_fair_pubdata_price = U256::from(fee_input.fair_l2_gas_price)
-                * (tx_gas_per_pubdata_limit - U256::from(1u32));
+            let new_fair_pubdata_price =
+                fair_l2_gas_price * (desired_gas_per_pubdata - U256::from(1u32));
 
             BatchFeeInput::PubdataIndependent(PubdataIndependentBatchFeeModelInput {
                 fair_pubdata_price: new_fair_pubdata_price.as_u64(),
+                fair_l2_gas_price: fair_l2_gas_price.as_u64(),
                 ..fee_input
             })
         }

core/lib/zksync_core/src/api_server/execution_sandbox/apply.rs

@@ -266,6 +266,7 @@ impl<'a> Sandbox<'a> {
             self.l1_batch_env.fee_input = adjust_pubdata_price_for_tx(
                 self.l1_batch_env.fee_input,
                 tx.gas_per_pubdata_byte_limit(),
+                self.l1_batch_env.enforced_base_fee.map(U256::from),
                 protocol_version.into(),
             );
         };

core/lib/zksync_core/src/api_server/tx_sender/mod.rs

@@ -12,7 +12,6 @@ use zksync_config::configs::{api::Web3JsonRpcConfig, chain::StateKeeperConfig};
 use zksync_contracts::BaseSystemContracts;
 use zksync_dal::{transactions_dal::L2TxSubmissionResult, ConnectionPool, StorageProcessor};
 use zksync_state::PostgresStorageCaches;
-use zksync_system_constants::DEFAULT_L2_TX_GAS_PER_PUBDATA_BYTE;
 use zksync_types::{
     fee::{Fee, TransactionExecutionMetrics},
     fee_model::BatchFeeInput,
@@ -653,6 +652,9 @@ impl TxSender {
             adjust_pubdata_price_for_tx(
                 fee_input,
                 tx.gas_per_pubdata_byte_limit(),
+                // We do not have to adjust the params to the `gasPrice` of the transaction, since
+                // its gas price will be amended later on to suit the `fee_input`
+                None,
                 protocol_version.into(),
             )
         };
@@ -706,9 +708,6 @@ impl TxSender {
             if l2_common_data.signature.is_empty() {
                 l2_common_data.signature = PackedEthSignature::default().serialize_packed().into();
             }
-
-            l2_common_data.fee.gas_per_pubdata_limit =
-                U256::from(DEFAULT_L2_TX_GAS_PER_PUBDATA_BYTE);
         }
 
         // Acquire the vm token for the whole duration of the binary search.