diff --git a/doc/release-notes.md b/doc/release-notes.md
--- a/doc/release-notes.md
+++ b/doc/release-notes.md
@@ -7,3 +7,6 @@
- Remove the bip9_softforks result from the getblockchaininfo RPC call.
- Remove the rules, vbavailable and vbrequired result from the getblocktemplate RPC call.
- Remove the rules argument from the getblocktemplate RPC call.
+ - Update fee calculation to add 179 effective bytes per transaction output in excess of inputs.
+ Refund 179 bytes worth of minimum fee per input in excess of outputs to a minimum of
+ 10 + 34 * (number of utxos)
diff --git a/src/primitives/transaction.h b/src/primitives/transaction.h
--- a/src/primitives/transaction.h
+++ b/src/primitives/transaction.h
@@ -312,6 +312,10 @@
// size)
unsigned int CalculateModifiedSize(unsigned int nTxSize = 0) const;
+ // Computes an adjusted tx size so that the UTXIs are billed partially
+ // upfront.
+ size_t GetBillableSize() const;
+
/**
* Get the total transaction size in bytes.
* @return Total transaction size in bytes
diff --git a/src/primitives/transaction.cpp b/src/primitives/transaction.cpp
--- a/src/primitives/transaction.cpp
+++ b/src/primitives/transaction.cpp
@@ -107,6 +107,24 @@
return nTxSize;
}
+size_t CTransaction::GetBillableSize() const {
+ size_t nTxSize = GetTotalSize(), inputs = vin.size(), outputs = vout.size();
+
+ // 179 bytes is the minimum size it would take to spend any outputs which
+ // are created. We want to change in advance of spending them to
+ // incentivize keeping your UTXO set reasonbly sized.
+ int64_t modSize =
+ int64_t(nTxSize) + (int64_t(outputs) - int64_t(inputs)) * 179;
+
+ // Note: It is impossible to generate a negative number above in any real
+ // world situation. This is because the inputs have a least 179 byte
+ // each. However, it is possible to have shorter scriptSigs than 179
+ // bytes. Therefore, we include a minimum of 10 bytes + 34 * vouts.
+ nTxSize = std::max(int64_t(outputs * 34 + 10), modSize);
+
+ return nTxSize;
+}
+
unsigned int CTransaction::GetTotalSize() const {
return ::GetSerializeSize(*this, SER_NETWORK, PROTOCOL_VERSION);
}
diff --git a/src/test/transaction_tests.cpp b/src/test/transaction_tests.cpp
--- a/src/test/transaction_tests.cpp
+++ b/src/test/transaction_tests.cpp
@@ -757,4 +757,24 @@
BOOST_CHECK(!IsStandardTx(CTransaction(t), reason));
}
+BOOST_AUTO_TEST_CASE(tx_transaction_fee) {
+ std::vector<size_t> sizes = {1, 2, 4, 8, 16, 32, 64, 128, 256, 512};
+ for (size_t inputs : sizes) {
+ for (size_t outputs : sizes) {
+ CMutableTransaction mtx;
+ mtx.vin.resize(inputs);
+ mtx.vout.resize(outputs);
+ CTransaction tx(mtx);
+ auto txBillableSize = tx.GetBillableSize();
+ auto txSize = tx.GetTotalSize();
+ BOOST_CHECK(txBillableSize > 0);
+ if (inputs > outputs) {
+ BOOST_CHECK(txBillableSize < txSize);
+ } else {
+ BOOST_CHECK(txBillableSize >= txSize);
+ }
+ }
+ }
+}
+
BOOST_AUTO_TEST_SUITE_END()
diff --git a/src/txmempool.h b/src/txmempool.h
--- a/src/txmempool.h
+++ b/src/txmempool.h
@@ -86,6 +86,8 @@
Amount nFee;
//!< ... and avoid recomputing tx size
size_t nTxSize;
+ //!< ... and billable size for billing
+ size_t nTxBillableSize;
//!< ... and modified size for priority
size_t nModSize;
//!< ... and total memory usage
@@ -143,6 +145,8 @@
double GetPriority(unsigned int currentHeight) const;
const Amount GetFee() const { return nFee; }
size_t GetTxSize() const { return nTxSize; }
+ size_t GetTxBillableSize() const { return nTxBillableSize; }
+
int64_t GetTime() const { return nTime; }
unsigned int GetHeight() const { return entryHeight; }
int64_t GetSigOpCount() const { return sigOpCount; }
diff --git a/src/txmempool.cpp b/src/txmempool.cpp
--- a/src/txmempool.cpp
+++ b/src/txmempool.cpp
@@ -32,6 +32,7 @@
spendsCoinbase(_spendsCoinbase), sigOpCount(_sigOpsCount),
lockPoints(lp) {
nTxSize = tx->GetTotalSize();
+ nTxBillableSize = tx->GetBillableSize();
nModSize = tx->CalculateModifiedSize(GetTxSize());
nUsageSize = RecursiveDynamicUsage(tx);
@@ -894,7 +895,7 @@
static TxMempoolInfo
GetInfo(CTxMemPool::indexed_transaction_set::const_iterator it) {
return TxMempoolInfo{it->GetSharedTx(), it->GetTime(),
- CFeeRate(it->GetFee(), it->GetTxSize()),
+ CFeeRate(it->GetFee(), it->GetTxBillableSize()),
it->GetModifiedFee() - it->GetFee()};
}
diff --git a/src/validation.cpp b/src/validation.cpp
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -883,6 +883,7 @@
chainActive.Height(), inChainInputValue,
fSpendsCoinbase, nSigOpsCount, lp);
unsigned int nSize = entry.GetTxSize();
+ size_t feeSize = tx.GetBillableSize();
// Check that the transaction doesn't have an excessive number of
// sigops, making it impossible to mine. Since the coinbase transaction
@@ -900,7 +901,7 @@
pool.GetMinFee(
gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) *
1000000)
- .GetFee(nSize);
+ .GetFee(feeSize);
if (mempoolRejectFee > Amount(0) && nModifiedFees < mempoolRejectFee) {
return state.DoS(0, false, REJECT_INSUFFICIENTFEE,
"mempool min fee not met", false,
@@ -908,7 +909,7 @@
}
if (gArgs.GetBoolArg("-relaypriority", DEFAULT_RELAYPRIORITY) &&
- nModifiedFees < minRelayTxFee.GetFee(nSize) &&
+ nModifiedFees < minRelayTxFee.GetFee(feeSize) &&
!AllowFree(entry.GetPriority(chainActive.Height() + 1))) {
// Require that free transactions have sufficient priority to be
// mined in the next block.
@@ -920,7 +921,7 @@
// This mitigates 'penny-flooding' -- sending thousands of free
// transactions just to be annoying or make others' transactions take
// longer to confirm.
- if (fLimitFree && nModifiedFees < minRelayTxFee.GetFee(nSize)) {
+ if (fLimitFree && nModifiedFees < minRelayTxFee.GetFee(feeSize)) {
static CCriticalSection csFreeLimiter;
static double dFreeCount;
static int64_t nLastTime;
@@ -933,6 +934,9 @@
nLastTime = nNow;
// -limitfreerelay unit is thousand-bytes-per-minute
// At default rate it would take over a month to fill 1GB
+
+ // NOTE: Use the actual size here, and not the fee size since this
+ // is counting real size for the rate limiter.
if (dFreeCount + nSize >=
gArgs.GetArg("-limitfreerelay", DEFAULT_LIMITFREERELAY) * 10 *
1000) {
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -2919,6 +2919,12 @@
CTransaction txNewConst(txNew);
unsigned int nBytes = txNewConst.GetTotalSize();
+
+ // Note: The relaying code has been changed to charge upfront for
+ // the minimum required bytes to spend a UTXO. This means that
+ // we need to calculate possible fees based that size.
+ size_t feeBytes = txNewConst.GetBillableSize();
+
dPriority = txNewConst.ComputePriority(dPriority, nBytes);
// Remove scriptSigs to eliminate the fee calculation dummy
@@ -2935,20 +2941,20 @@
}
Amount nFeeNeeded =
- GetMinimumFee(nBytes, currentConfirmationTarget, mempool);
+ GetMinimumFee(feeBytes, currentConfirmationTarget, mempool);
if (coinControl && nFeeNeeded > Amount(0) &&
coinControl->nMinimumTotalFee > nFeeNeeded) {
nFeeNeeded = coinControl->nMinimumTotalFee;
}
if (coinControl && coinControl->fOverrideFeeRate) {
- nFeeNeeded = coinControl->nFeeRate.GetFee(nBytes);
+ nFeeNeeded = coinControl->nFeeRate.GetFee(feeBytes);
}
// If we made it here and we aren't even able to meet the relay fee
// on the next pass, give up because we must be at the maximum
// allowed fee.
- Amount minFee = GetConfig().GetMinFeePerKB().GetFee(nBytes);
+ Amount minFee = GetConfig().GetMinFeePerKB().GetFee(feeBytes);
if (nFeeNeeded < minFee) {
strFailReason = _("Transaction too large for fee policy");
return false;
diff --git a/test/functional/fundrawtransaction.py b/test/functional/fundrawtransaction.py
--- a/test/functional/fundrawtransaction.py
+++ b/test/functional/fundrawtransaction.py
@@ -151,7 +151,7 @@
inputs = [{'txid': utx['txid'], 'vout': utx['vout']}]
outputs = {
- self.nodes[0].getnewaddress(): Decimal(5.0) - fee - feeTolerance}
+ self.nodes[0].getnewaddress(): satoshi_round(Decimal(5.0) - fee - feeTolerance)}
rawtx = self.nodes[2].createrawtransaction(inputs, outputs)
dec_tx = self.nodes[2].decoderawtransaction(rawtx)
assert_equal(utx['txid'], dec_tx['vin'][0]['txid'])
diff --git a/test/functional/mempool_limit.py b/test/functional/mempool_limit.py
--- a/test/functional/mempool_limit.py
+++ b/test/functional/mempool_limit.py
@@ -21,7 +21,7 @@
relayfee = self.nodes[0].getnetworkinfo()['relayfee']
txids = []
- utxos = create_confirmed_utxos(relayfee, self.nodes[0], 91)
+ utxos = create_confirmed_utxos(relayfee, self.nodes[0], 121)
# create a mempool tx that will be evicted
us0 = utxos.pop()
@@ -38,7 +38,7 @@
relayfee = self.nodes[0].getnetworkinfo()['relayfee']
base_fee = relayfee * 100
- for i in range(3):
+ for i in range(4):
txids.append([])
txids[i] = create_lots_of_big_transactions(
self.nodes[0], txouts, utxos[30 * i:30 * i + 30], 30, (i + 1) * base_fee)
diff --git a/test/functional/test_framework/mininode.py b/test/functional/test_framework/mininode.py
--- a/test/functional/test_framework/mininode.py
+++ b/test/functional/test_framework/mininode.py
@@ -412,7 +412,8 @@
for vout in self.vout:
# Include the sizes for the outputs.
tx_size += len(ToHex(vout))//2
- return tx_size
+ tx_size += (len(self.vout) - len(self.vin))*179
+ return max(tx_size, 10 + 34 * len(self.vout))
def serialize(self):
r = b""
diff --git a/test/functional/test_framework/test_node.py b/test/functional/test_framework/test_node.py
--- a/test/functional/test_framework/test_node.py
+++ b/test/functional/test_framework/test_node.py
@@ -167,7 +167,7 @@
def calculate_fee(self, tx):
# Relay fee is in satoshis per KB. Thus the 1000, and the COIN added
# to get back to an amount of satoshis.
- return int(self.relay_fee() / 1000 * len(ToHex(tx)) * COIN)
+ return int(self.relay_fee() / 1000 * tx.billable_size() * COIN)
def calculate_fee_from_txid(self, txid):
ctx = FromHex(CTransaction(), self.getrawtransaction(txid))
diff --git a/test/functional/wallet.py b/test/functional/wallet.py
--- a/test/functional/wallet.py
+++ b/test/functional/wallet.py
@@ -5,6 +5,9 @@
"""Test the wallet."""
from test_framework.test_framework import BitcoinTestFramework
from test_framework.util import *
+from test_framework.mininode import *
+
+import io
class WalletTest(BitcoinTestFramework):
@@ -159,8 +162,9 @@
txid = self.nodes[2].sendtoaddress(address, 10, "", "", False)
self.nodes[2].generate(1)
self.sync_all([self.nodes[0:3]])
+ ctx = FromHex(CTransaction(), self.nodes[2].getrawtransaction(txid))
node_2_bal = self.check_fee_amount(self.nodes[2].getbalance(), Decimal(
- '84'), fee_per_byte, count_bytes(self.nodes[2].getrawtransaction(txid)))
+ '84'), fee_per_byte, ctx.billable_size())
assert_equal(self.nodes[0].getbalance(), Decimal('10'))
# Send 10 BTC with subtract fee from amount
@@ -177,8 +181,9 @@
self.nodes[2].generate(1)
self.sync_all([self.nodes[0:3]])
node_0_bal += Decimal('10')
+ ctx = FromHex(CTransaction(), self.nodes[2].getrawtransaction(txid))
node_2_bal = self.check_fee_amount(self.nodes[2].getbalance(
- ), node_2_bal - Decimal('10'), fee_per_byte, count_bytes(self.nodes[2].getrawtransaction(txid)))
+ ), node_2_bal - Decimal('10'), fee_per_byte, ctx.billable_size())
assert_equal(self.nodes[0].getbalance(), node_0_bal)
# Sendmany 10 BTC with subtract fee from amount
@@ -187,8 +192,9 @@
self.sync_all([self.nodes[0:3]])
node_2_bal -= Decimal('10')
assert_equal(self.nodes[2].getbalance(), node_2_bal)
+ ctx = FromHex(CTransaction(), self.nodes[2].getrawtransaction(txid))
node_0_bal = self.check_fee_amount(self.nodes[0].getbalance(
- ), node_0_bal + Decimal('10'), fee_per_byte, count_bytes(self.nodes[2].getrawtransaction(txid)))
+ ), node_0_bal + Decimal('10'), fee_per_byte, ctx.billable_size())
# Test ResendWalletTransactions:
# Create a couple of transactions, then start up a fourth