NDEV-2111 mempool: increase gas-price on full mempool

proxy/mempool/mempool.py

@@ -1,4 +1,5 @@
 import asyncio
+import dataclasses
 import logging
 import math
 import time
@@ -150,6 +151,9 @@ def get_pending_tx_by_sender_nonce(self, sender_addr: str, tx_nonce: int) -> MPN
         return self._completed_tx_dict.get_tx_by_sender_nonce(sender_addr, tx_nonce)
 
     def get_gas_price(self) -> Optional[MPGasPriceResult]:
+        min_gas_price = self._tx_schedule.min_gas_price
+        if min_gas_price > self._gas_price.suggested_gas_price:
+            return dataclasses.replace(self._gas_price, suggested_gas_price=min_gas_price)
         return self._gas_price
 
     @staticmethod

proxy/mempool/mempool_schedule.py

@@ -259,6 +259,16 @@ def __init__(self, capacity: int) -> None:
         )
         self._suspended_sender_set: Set[str] = set()
 
+    @property
+    def min_gas_price(self) -> int:
+        if self.tx_cnt < int(self._capacity * 0.9):  # if there are more than 90%
+            return 0
+
+        lower_tx = self._tx_dict.peek_lower_tx()
+        if not lower_tx:
+            return 0
+        return int(lower_tx.gas_price * 1.3)  # increase gas-price in 30%
+
     def _add_tx_to_sender_pool(self, sender_pool: MPSenderTxPool, tx: MPTxRequest) -> None:
         LOG.debug(f'Add tx {tx.sig} to mempool with {self.tx_cnt} txs')