// Test suite for ancestor feerate transaction selection. // Implemented as an additional function, rather than a separate test case, // to allow reusing the blockchain created in CreateNewBlock_validity. void TestPackageSelection(const CChainParams& chainparams, CScript scriptPubKey, std::vector<CTransactionRef>& txFirst) { // Test the ancestor feerate transaction selection. TestMemPoolEntryHelper entry; // Test that a medium fee transaction will be selected after a higher fee // rate package with a low fee rate parent. CMutableTransaction tx; tx.vin.resize(1); tx.vin[0].scriptSig = CScript() << OP_1; tx.vin[0].prevout.hash = txFirst[0]->GetHash(); tx.vin[0].prevout.n = 0; tx.vout.resize(1); tx.vout[0].nValue = 5000000000LL - 1000; // This tx has a low fee: 1000 satoshis uint256 hashParentTx = tx.GetHash(); // save this txid for later use mempool.addUnchecked(hashParentTx, entry.Fee(1000).Time(GetTime()).SpendsCoinbase(true).FromTx(tx)); // This tx has a medium fee: 10000 satoshis tx.vin[0].prevout.hash = txFirst[1]->GetHash(); tx.vout[0].nValue = 5000000000LL - 10000; uint256 hashMediumFeeTx = tx.GetHash(); mempool.addUnchecked(hashMediumFeeTx, entry.Fee(10000).Time(GetTime()).SpendsCoinbase(true).FromTx(tx)); // This tx has a high fee, but depends on the first transaction tx.vin[0].prevout.hash = hashParentTx; tx.vout[0].nValue = 5000000000LL - 1000 - 50000; // 50k satoshi fee uint256 hashHighFeeTx = tx.GetHash(); mempool.addUnchecked(hashHighFeeTx, entry.Fee(50000).Time(GetTime()).SpendsCoinbase(false).FromTx(tx)); std::unique_ptr<CBlockTemplate> pblocktemplate = AssemblerForTest(chainparams).CreateNewBlock(scriptPubKey); BOOST_CHECK(pblocktemplate->block.vtx[1]->GetHash() == hashParentTx); BOOST_CHECK(pblocktemplate->block.vtx[2]->GetHash() == hashHighFeeTx); BOOST_CHECK(pblocktemplate->block.vtx[3]->GetHash() == hashMediumFeeTx); // Test that a package below the block min tx fee doesn't get included tx.vin[0].prevout.hash = hashHighFeeTx; tx.vout[0].nValue = 5000000000LL - 1000 - 50000; // 0 fee uint256 hashFreeTx = tx.GetHash(); mempool.addUnchecked(hashFreeTx, entry.Fee(0).FromTx(tx)); size_t freeTxSize = ::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION); // Calculate a fee on child transaction that will put the package just // below the block min tx fee (assuming 1 child tx of the same size). CAmount feeToUse = blockMinFeeRate.GetFee(2*freeTxSize) - 1; tx.vin[0].prevout.hash = hashFreeTx; tx.vout[0].nValue = 5000000000LL - 1000 - 50000 - feeToUse; uint256 hashLowFeeTx = tx.GetHash(); mempool.addUnchecked(hashLowFeeTx, entry.Fee(feeToUse).FromTx(tx)); pblocktemplate = AssemblerForTest(chainparams).CreateNewBlock(scriptPubKey); // Verify that the free tx and the low fee tx didn't get selected for (size_t i=0; i<pblocktemplate->block.vtx.size(); ++i) { BOOST_CHECK(pblocktemplate->block.vtx[i]->GetHash() != hashFreeTx); BOOST_CHECK(pblocktemplate->block.vtx[i]->GetHash() != hashLowFeeTx); } // Test that packages above the min relay fee do get included, even if one // of the transactions is below the min relay fee // Remove the low fee transaction and replace with a higher fee transaction mempool.removeRecursive(tx); tx.vout[0].nValue -= 2; // Now we should be just over the min relay fee hashLowFeeTx = tx.GetHash(); mempool.addUnchecked(hashLowFeeTx, entry.Fee(feeToUse+2).FromTx(tx)); pblocktemplate = AssemblerForTest(chainparams).CreateNewBlock(scriptPubKey); BOOST_CHECK(pblocktemplate->block.vtx[4]->GetHash() == hashFreeTx); BOOST_CHECK(pblocktemplate->block.vtx[5]->GetHash() == hashLowFeeTx); // Test that transaction selection properly updates ancestor fee // calculations as ancestor transactions get included in a block. // Add a 0-fee transaction that has 2 outputs. tx.vin[0].prevout.hash = txFirst[2]->GetHash(); tx.vout.resize(2); tx.vout[0].nValue = 5000000000LL - 100000000; tx.vout[1].nValue = 100000000; // 1BTC output uint256 hashFreeTx2 = tx.GetHash(); mempool.addUnchecked(hashFreeTx2, entry.Fee(0).SpendsCoinbase(true).FromTx(tx)); // This tx can't be mined by itself tx.vin[0].prevout.hash = hashFreeTx2; tx.vout.resize(1); feeToUse = blockMinFeeRate.GetFee(freeTxSize); tx.vout[0].nValue = 5000000000LL - 100000000 - feeToUse; uint256 hashLowFeeTx2 = tx.GetHash(); mempool.addUnchecked(hashLowFeeTx2, entry.Fee(feeToUse).SpendsCoinbase(false).FromTx(tx)); pblocktemplate = AssemblerForTest(chainparams).CreateNewBlock(scriptPubKey); // Verify that this tx isn't selected. for (size_t i=0; i<pblocktemplate->block.vtx.size(); ++i) { BOOST_CHECK(pblocktemplate->block.vtx[i]->GetHash() != hashFreeTx2); BOOST_CHECK(pblocktemplate->block.vtx[i]->GetHash() != hashLowFeeTx2); } // This tx will be mineable, and should cause hashLowFeeTx2 to be selected // as well. tx.vin[0].prevout.n = 1; tx.vout[0].nValue = 100000000 - 10000; // 10k satoshi fee mempool.addUnchecked(tx.GetHash(), entry.Fee(10000).FromTx(tx)); pblocktemplate = AssemblerForTest(chainparams).CreateNewBlock(scriptPubKey); BOOST_CHECK(pblocktemplate->block.vtx[8]->GetHash() == hashLowFeeTx2); }
uint256 hashParentTx = tx.GetHash(); // save this txid for later use mempool.addUnchecked(entry.Fee(1000).Time(GetTime()).SpendsCoinbase(true).FromTx(tx)); // This tx has a medium fee: 10000 satoshis tx.vin[0].prevout.hash = txFirst[1]->GetHash(); tx.vout[0].nValue = 5000000000LL - 10000; uint256 hashMediumFeeTx = tx.GetHash(); mempool.addUnchecked(entry.Fee(10000).Time(GetTime()).SpendsCoinbase(true).FromTx(tx)); // This tx has a high fee, but depends on the first transaction tx.vin[0].prevout.hash = hashParentTx; tx.vout[0].nValue = 5000000000LL - 1000 - 50000; // 50k satoshi fee uint256 hashHighFeeTx = tx.GetHash(); mempool.addUnchecked(entry.Fee(50000).Time(GetTime()).SpendsCoinbase(false).FromTx(tx)); std::unique_ptr<CBlockTemplate> pblocktemplate = AssemblerForTest(chainparams).CreateNewBlock(scriptPubKey); BOOST_CHECK(pblocktemplate->block.vtx[1]->GetHash() == hashParentTx); BOOST_CHECK(pblocktemplate->block.vtx[2]->GetHash() == hashHighFeeTx); BOOST_CHECK(pblocktemplate->block.vtx[3]->GetHash() == hashMediumFeeTx); // Test that a package below the block min tx fee doesn't get included tx.vin[0].prevout.hash = hashHighFeeTx; tx.vout[0].nValue = 5000000000LL - 1000 - 50000; // 0 fee uint256 hashFreeTx = tx.GetHash(); mempool.addUnchecked(entry.Fee(0).FromTx(tx)); size_t freeTxSize = ::GetSerializeSize(tx, PROTOCOL_VERSION); // Calculate a fee on child transaction that will put the package just // below the block min tx fee (assuming 1 child tx of the same size). CAmount feeToUse = blockMinFeeRate.GetFee(2*freeTxSize) - 1;