mempool_updatefromblock.py
1 #!/usr/bin/env python3 2 # Copyright (c) 2020-present The Bitcoin Core developers 3 # Distributed under the MIT software license, see the accompanying 4 # file COPYING or http://www.opensource.org/licenses/mit-license.php. 5 """Test mempool descendants/ancestors information update. 6 7 Test mempool update of transaction descendants/ancestors information (count, size) 8 when transactions have been re-added from a disconnected block to the mempool. 9 """ 10 from decimal import Decimal 11 from math import ceil 12 import time 13 14 from test_framework.blocktools import create_empty_fork 15 from test_framework.test_framework import BitcoinTestFramework 16 from test_framework.util import assert_equal, assert_greater_than_or_equal, assert_raises_rpc_error 17 from test_framework.wallet import MiniWallet 18 from test_framework.mempool_util import DEFAULT_CLUSTER_LIMIT 19 20 MAX_DISCONNECTED_TX_POOL_BYTES = 20_000_000 21 22 class MempoolUpdateFromBlockTest(BitcoinTestFramework): 23 def set_test_params(self): 24 self.num_nodes = 1 25 self.extra_args = [['-limitclustersize=1000']] 26 27 def trigger_reorg(self, fork_blocks): 28 """Trigger reorg of the fork blocks.""" 29 for block in fork_blocks: 30 self.nodes[0].submitblock(block.serialize().hex()) 31 assert_equal(self.nodes[0].getbestblockhash(), fork_blocks[-1].hash_hex) 32 33 def transaction_graph_test(self, size, *, n_tx_to_mine, fee=100_000): 34 """Create an acyclic tournament (a type of directed graph) of transactions and use it for testing. 35 36 Keyword arguments: 37 size -- the order N of the tournament which is equal to the number of the created transactions 38 n_tx_to_mine -- the number of transactions that should be mined into a block 39 40 If all of the N created transactions tx[0]..tx[N-1] reside in the mempool, 41 the following holds: 42 the tx[K] transaction: 43 - has N-K descendants (including this one), and 44 - has K+1 ancestors (including this one) 45 46 More details: https://en.wikipedia.org/wiki/Tournament_(graph_theory) 47 """ 48 wallet = MiniWallet(self.nodes[0]) 49 50 # Prep for fork with empty blocks to not use invalidateblock directly 51 # for reorg case. The rpc has different codepath 52 fork_blocks = create_empty_fork(self.nodes[0], fork_length=7) 53 54 tx_id = [] 55 tx_size = [] 56 self.log.info('Creating {} transactions...'.format(size)) 57 for i in range(0, size): 58 self.log.debug('Preparing transaction #{}...'.format(i)) 59 # Prepare inputs. 60 if i == 0: 61 inputs = [wallet.get_utxo()] # let MiniWallet provide a start UTXO 62 else: 63 inputs = [] 64 for j, tx in enumerate(tx_id[0:i]): 65 # Transaction tx[K] is a child of each of previous transactions tx[0]..tx[K-1] at their output K-1. 66 vout = i - j - 1 67 inputs.append(wallet.get_utxo(txid=tx_id[j], vout=vout)) 68 69 # Prepare outputs. 70 tx_count = i + 1 71 if tx_count < size: 72 # Transaction tx[K] is an ancestor of each of subsequent transactions tx[K+1]..tx[N-1]. 73 n_outputs = size - tx_count 74 else: 75 n_outputs = 1 76 77 # Create a new transaction. 78 new_tx = wallet.send_self_transfer_multi( 79 from_node=self.nodes[0], 80 utxos_to_spend=inputs, 81 num_outputs=n_outputs, 82 fee_per_output=ceil(fee / n_outputs) 83 ) 84 tx_id.append(new_tx['txid']) 85 tx_size.append(new_tx['tx'].get_vsize()) 86 87 if tx_count in n_tx_to_mine: 88 # The created transactions are mined into blocks by batches. 89 self.log.info('The batch of {} transactions has been accepted into the mempool.'.format(len(self.nodes[0].getrawmempool()))) 90 self.generate(self.nodes[0], 1)[0] 91 assert_equal(len(self.nodes[0].getrawmempool()), 0) 92 self.log.info('All of the transactions from the current batch have been mined into a block.') 93 elif tx_count == size: 94 # At the end the old fork is submitted to cause reorg, and all of the created 95 # transactions should be re-added from disconnected blocks to the mempool. 96 self.log.info('The last batch of {} transactions has been accepted into the mempool.'.format(len(self.nodes[0].getrawmempool()))) 97 start = time.time() 98 # Trigger reorg 99 for block in fork_blocks: 100 self.nodes[0].submitblock(block.serialize().hex()) 101 end = time.time() 102 assert_equal(len(self.nodes[0].getrawmempool()), size) 103 self.log.info('All of the recently mined transactions have been re-added into the mempool in {} seconds.'.format(end - start)) 104 105 self.log.info('Checking descendants/ancestors properties of all of the in-mempool transactions...') 106 for k, tx in enumerate(tx_id): 107 self.log.debug('Check transaction #{}.'.format(k)) 108 entry = self.nodes[0].getmempoolentry(tx) 109 assert_equal(entry['descendantcount'], size - k) 110 assert_equal(entry['descendantsize'], sum(tx_size[k:size])) 111 assert_equal(entry['ancestorcount'], k + 1) 112 assert_equal(entry['ancestorsize'], sum(tx_size[0:(k + 1)])) 113 114 self.generate(self.nodes[0], 1) 115 assert_equal(self.nodes[0].getrawmempool(), []) 116 wallet.rescan_utxos() 117 118 def test_max_disconnect_pool_bytes(self): 119 self.log.info('Creating independent transactions to test MAX_DISCONNECTED_TX_POOL_BYTES limit during reorg') 120 121 # Generate coins for the hundreds of transactions we will make 122 parent_target_vsize = 100_000 123 wallet = MiniWallet(self.nodes[0]) 124 self.generate(wallet, (MAX_DISCONNECTED_TX_POOL_BYTES // parent_target_vsize) + 100) 125 126 assert_equal(self.nodes[0].getrawmempool(), []) 127 128 # Set up empty fork blocks ahead of time, needs to be longer than full fork made later 129 fork_blocks = create_empty_fork(self.nodes[0], fork_length=60) 130 131 large_std_txs = [] 132 # Add children to ensure they're recursively removed if disconnectpool trimming of parent occurs 133 small_child_txs = [] 134 aggregate_serialized_size = 0 135 while aggregate_serialized_size < MAX_DISCONNECTED_TX_POOL_BYTES: 136 # Mine parents in FIFO order via fee ordering 137 large_std_txs.append(wallet.create_self_transfer(target_vsize=parent_target_vsize, fee=Decimal("0.00400000") - (Decimal("0.00001000") * len(large_std_txs)))) 138 small_child_txs.append(wallet.create_self_transfer(utxo_to_spend=large_std_txs[-1]['new_utxo'])) 139 # Slight underestimate of dynamic cost, so we'll be over during reorg 140 aggregate_serialized_size += len(large_std_txs[-1]["tx"].serialize()) 141 142 for large_std_tx in large_std_txs: 143 self.nodes[0].sendrawtransaction(large_std_tx["hex"]) 144 145 assert_equal(self.nodes[0].getmempoolinfo()["size"], len(large_std_txs)) 146 147 # Mine non-empty chain that will be reorged shortly 148 self.generate(self.nodes[0], len(fork_blocks) - 1) 149 assert_equal(self.nodes[0].getrawmempool(), []) 150 151 # Stick children in mempool, evicted with parent potentially 152 for small_child_tx in small_child_txs: 153 self.nodes[0].sendrawtransaction(small_child_tx["hex"]) 154 155 assert_equal(self.nodes[0].getmempoolinfo()["size"], len(small_child_txs)) 156 157 # Reorg back before the first block in the series, should drop something 158 # but not all, and any time parent is dropped, child is also removed 159 self.trigger_reorg(fork_blocks=fork_blocks) 160 mempool = self.nodes[0].getrawmempool() 161 # At least one parent must be dropped, but more may be dropped, 162 # depending on the dynamic cost overhead. 163 expected_parent_count = len(large_std_txs) - 1 164 assert_greater_than_or_equal(expected_parent_count * 2, len(mempool)) 165 expected_parent_count = len(mempool) // 2 166 167 parent_presence = [tx["txid"] in mempool for tx in large_std_txs] 168 169 # The txns at the end of the list, or most recently confirmed, should have been trimmed 170 assert_equal(parent_presence, [tx["txid"] in mempool for tx in small_child_txs]) 171 assert_equal(parent_presence, [True] * expected_parent_count + [False] * (len(large_std_txs) - expected_parent_count)) 172 173 def test_chainlimits_exceeded(self): 174 self.log.info('Check that too long chains on reorg are handled') 175 176 wallet = MiniWallet(self.nodes[0]) 177 self.generate(wallet, 101) 178 179 assert_equal(self.nodes[0].getrawmempool(), []) 180 181 # Prep fork 182 fork_blocks = create_empty_fork(self.nodes[0]) 183 184 # Two higher than descendant count 185 chain = wallet.create_self_transfer_chain(chain_length=DEFAULT_CLUSTER_LIMIT + 2) 186 for tx in chain[:-2]: 187 self.nodes[0].sendrawtransaction(tx["hex"]) 188 189 assert_raises_rpc_error(-26, "too-large-cluster", self.nodes[0].sendrawtransaction, chain[-2]["hex"]) 190 191 # Mine a block with all but last transaction, non-standardly long chain 192 self.generateblock(self.nodes[0], output="raw(42)", transactions=[tx["hex"] for tx in chain[:-1]]) 193 assert_equal(self.nodes[0].getrawmempool(), []) 194 195 # Last tx fits now 196 self.nodes[0].sendrawtransaction(chain[-1]["hex"]) 197 198 # Finally, reorg to empty chain to kick everything back into mempool 199 # at normal chain limits 200 for block in fork_blocks: 201 self.nodes[0].submitblock(block.serialize().hex()) 202 mempool = self.nodes[0].getrawmempool() 203 assert_equal(set(mempool), set([tx["txid"] for tx in chain[:-2]])) 204 205 def run_test(self): 206 # Mine in batches of 25 to test multi-block reorg under chain limits 207 self.transaction_graph_test(size=DEFAULT_CLUSTER_LIMIT, n_tx_to_mine=[25, 50, 75]) 208 209 self.test_max_disconnect_pool_bytes() 210 211 self.test_chainlimits_exceeded() 212 213 if __name__ == '__main__': 214 MempoolUpdateFromBlockTest(__file__).main()