bitcoin/test/functional/mempool_limit.py
2023-04-17 12:35:23 +01:00

155 lines
8.7 KiB
Python
Executable File

#!/usr/bin/env python3
# Copyright (c) 2014-2022 The Bitcoin Core developers
# Distributed under the MIT software license, see the accompanying
# file COPYING or http://www.opensource.org/licenses/mit-license.php.
"""Test mempool limiting together/eviction with the wallet."""
from decimal import Decimal
from test_framework.blocktools import COINBASE_MATURITY
from test_framework.p2p import P2PTxInvStore
from test_framework.test_framework import BitcoinTestFramework
from test_framework.util import (
assert_equal,
assert_fee_amount,
assert_greater_than,
assert_raises_rpc_error,
create_lots_of_big_transactions,
gen_return_txouts,
)
from test_framework.wallet import (
COIN,
DEFAULT_FEE,
MiniWallet,
)
class MempoolLimitTest(BitcoinTestFramework):
def set_test_params(self):
self.setup_clean_chain = True
self.num_nodes = 1
self.extra_args = [[
"-datacarriersize=100000",
"-maxmempool=5",
]]
self.supports_cli = False
def run_test(self):
txouts = gen_return_txouts()
node = self.nodes[0]
miniwallet = MiniWallet(node)
relayfee = node.getnetworkinfo()['relayfee']
self.log.info('Check that mempoolminfee is minrelaytxfee')
assert_equal(node.getmempoolinfo()['minrelaytxfee'], Decimal('0.00001000'))
assert_equal(node.getmempoolinfo()['mempoolminfee'], Decimal('0.00001000'))
tx_batch_size = 1
num_of_batches = 75
# Generate UTXOs to flood the mempool
# 1 to create a tx initially that will be evicted from the mempool later
# 3 batches of multiple transactions with a fee rate much higher than the previous UTXO
# And 1 more to verify that this tx does not get added to the mempool with a fee rate less than the mempoolminfee
# And 2 more for the package cpfp test
self.generate(miniwallet, 1 + (num_of_batches * tx_batch_size) + 1 + 2)
# Mine 99 blocks so that the UTXOs are allowed to be spent
self.generate(node, COINBASE_MATURITY - 1)
self.log.info('Create a mempool tx that will be evicted')
tx_to_be_evicted_id = miniwallet.send_self_transfer(from_node=node, fee_rate=relayfee)["txid"]
# Increase the tx fee rate to give the subsequent transactions a higher priority in the mempool
# The tx has an approx. vsize of 65k, i.e. multiplying the previous fee rate (in sats/kvB)
# by 130 should result in a fee that corresponds to 2x of that fee rate
base_fee = relayfee * 130
self.log.info("Fill up the mempool with txs with higher fee rate")
for batch_of_txid in range(num_of_batches):
fee = (batch_of_txid + 1) * base_fee
create_lots_of_big_transactions(miniwallet, node, fee, tx_batch_size, txouts)
self.log.info('The tx should be evicted by now')
# The number of transactions created should be greater than the ones present in the mempool
assert_greater_than(tx_batch_size * num_of_batches, len(node.getrawmempool()))
# Initial tx created should not be present in the mempool anymore as it had a lower fee rate
assert tx_to_be_evicted_id not in node.getrawmempool()
self.log.info('Check that mempoolminfee is larger than minrelaytxfee')
assert_equal(node.getmempoolinfo()['minrelaytxfee'], Decimal('0.00001000'))
assert_greater_than(node.getmempoolinfo()['mempoolminfee'], Decimal('0.00001000'))
# Deliberately try to create a tx with a fee less than the minimum mempool fee to assert that it does not get added to the mempool
self.log.info('Create a mempool tx that will not pass mempoolminfee')
assert_raises_rpc_error(-26, "mempool min fee not met", miniwallet.send_self_transfer, from_node=node, fee_rate=relayfee)
self.log.info("Check that submitpackage allows cpfp of a parent below mempool min feerate")
node = self.nodes[0]
peer = node.add_p2p_connection(P2PTxInvStore())
# Package with 2 parents and 1 child. One parent has a high feerate due to modified fees,
# another is below the mempool minimum feerate but bumped by the child.
tx_poor = miniwallet.create_self_transfer(fee_rate=relayfee)
tx_rich = miniwallet.create_self_transfer(fee=0, fee_rate=0)
node.prioritisetransaction(tx_rich["txid"], 0, int(DEFAULT_FEE * COIN))
package_txns = [tx_rich, tx_poor]
coins = [tx["new_utxo"] for tx in package_txns]
tx_child = miniwallet.create_self_transfer_multi(utxos_to_spend=coins, fee_per_output=10000) #DEFAULT_FEE
package_txns.append(tx_child)
submitpackage_result = node.submitpackage([tx["hex"] for tx in package_txns])
rich_parent_result = submitpackage_result["tx-results"][tx_rich["wtxid"]]
poor_parent_result = submitpackage_result["tx-results"][tx_poor["wtxid"]]
child_result = submitpackage_result["tx-results"][tx_child["tx"].getwtxid()]
assert_fee_amount(poor_parent_result["fees"]["base"], tx_poor["tx"].get_vsize(), relayfee)
assert_equal(rich_parent_result["fees"]["base"], 0)
assert_equal(child_result["fees"]["base"], DEFAULT_FEE)
# The "rich" parent does not require CPFP so its effective feerate is just its individual feerate.
assert_fee_amount(DEFAULT_FEE, tx_rich["tx"].get_vsize(), rich_parent_result["fees"]["effective-feerate"])
assert_equal(rich_parent_result["fees"]["effective-includes"], [tx_rich["wtxid"]])
# The "poor" parent and child's effective feerates are the same, composed of their total
# fees divided by their combined vsize.
package_fees = poor_parent_result["fees"]["base"] + child_result["fees"]["base"]
package_vsize = tx_poor["tx"].get_vsize() + tx_child["tx"].get_vsize()
assert_fee_amount(package_fees, package_vsize, poor_parent_result["fees"]["effective-feerate"])
assert_fee_amount(package_fees, package_vsize, child_result["fees"]["effective-feerate"])
assert_equal([tx_poor["wtxid"], tx_child["tx"].getwtxid()], poor_parent_result["fees"]["effective-includes"])
assert_equal([tx_poor["wtxid"], tx_child["tx"].getwtxid()], child_result["fees"]["effective-includes"])
# The node will broadcast each transaction, still abiding by its peer's fee filter
peer.wait_for_broadcast([tx["tx"].getwtxid() for tx in package_txns])
self.log.info("Check a package that passes mempoolminfee but is evicted immediately after submission")
mempoolmin_feerate = node.getmempoolinfo()["mempoolminfee"]
current_mempool = node.getrawmempool(verbose=False)
worst_feerate_btcvb = Decimal("21000000")
for txid in current_mempool:
entry = node.getmempoolentry(txid)
worst_feerate_btcvb = min(worst_feerate_btcvb, entry["fees"]["descendant"] / entry["descendantsize"])
# Needs to be large enough to trigger eviction
target_weight_each = 200000
assert_greater_than(target_weight_each * 2, node.getmempoolinfo()["maxmempool"] - node.getmempoolinfo()["bytes"])
# Should be a true CPFP: parent's feerate is just below mempool min feerate
parent_fee = (mempoolmin_feerate / 1000) * (target_weight_each // 4) - Decimal("0.00001")
# Parent + child is above mempool minimum feerate
child_fee = (worst_feerate_btcvb) * (target_weight_each // 4) - Decimal("0.00001")
# However, when eviction is triggered, these transactions should be at the bottom.
# This assertion assumes parent and child are the same size.
miniwallet.rescan_utxos()
tx_parent_just_below = miniwallet.create_self_transfer(fee=parent_fee, target_weight=target_weight_each)
tx_child_just_above = miniwallet.create_self_transfer(utxo_to_spend=tx_parent_just_below["new_utxo"], fee=child_fee, target_weight=target_weight_each)
# This package ranks below the lowest descendant package in the mempool
assert_greater_than(worst_feerate_btcvb, (parent_fee + child_fee) / (tx_parent_just_below["tx"].get_vsize() + tx_child_just_above["tx"].get_vsize()))
assert_greater_than(mempoolmin_feerate, (parent_fee) / (tx_parent_just_below["tx"].get_vsize()))
assert_greater_than((parent_fee + child_fee) / (tx_parent_just_below["tx"].get_vsize() + tx_child_just_above["tx"].get_vsize()), mempoolmin_feerate / 1000)
assert_raises_rpc_error(-26, "mempool full", node.submitpackage, [tx_parent_just_below["hex"], tx_child_just_above["hex"]])
self.log.info('Test passing a value below the minimum (5 MB) to -maxmempool throws an error')
self.stop_node(0)
self.nodes[0].assert_start_raises_init_error(["-maxmempool=4"], "Error: -maxmempool must be at least 5 MB")
if __name__ == '__main__':
MempoolLimitTest().main()