diff options
| -rw-r--r-- | src/wallet/wallet.cpp | 31 | ||||
| -rw-r--r-- | src/wallet/wallet.h | 3 |
2 files changed, 32 insertions, 2 deletions
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp index 13da7bb2c2..e230ee0eb0 100644 --- a/src/wallet/wallet.cpp +++ b/src/wallet/wallet.cpp @@ -57,6 +57,8 @@ CFeeRate CWallet::minTxFee = CFeeRate(DEFAULT_TRANSACTION_MINFEE); */ CFeeRate CWallet::fallbackFee = CFeeRate(DEFAULT_FALLBACK_FEE); +CFeeRate CWallet::m_discard_rate = CFeeRate(DEFAULT_DISCARD_FEE); + const uint256 CMerkleTx::ABANDON_HASH(uint256S("0000000000000000000000000000000000000000000000000000000000000001")); /** @defgroup mapWallet @@ -2501,6 +2503,17 @@ bool CWallet::FundTransaction(CMutableTransaction& tx, CAmount& nFeeRet, int& nC return true; } +static CFeeRate GetDiscardRate(const CBlockPolicyEstimator& estimator) +{ + unsigned int highest_target = estimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE); + CFeeRate discard_rate = estimator.estimateSmartFee(highest_target, nullptr /* FeeCalculation */, false /* conservative */); + // Don't let discard_rate be greater than longest possible fee estimate if we get a valid fee estimate + discard_rate = (discard_rate == CFeeRate(0)) ? CWallet::m_discard_rate : std::min(discard_rate, CWallet::m_discard_rate); + // Discard rate must be at least dustRelayFee + discard_rate = std::max(discard_rate, ::dustRelayFee); + return discard_rate; +} + bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CWalletTx& wtxNew, CReserveKey& reservekey, CAmount& nFeeRet, int& nChangePosInOut, std::string& strFailReason, const CCoinControl& coin_control, bool sign) { @@ -2600,6 +2613,7 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CWalletT CTxOut change_prototype_txout(0, scriptChange); size_t change_prototype_size = GetSerializeSize(change_prototype_txout, SER_DISK, 0); + CFeeRate discard_rate = GetDiscardRate(::feeEstimator); nFeeRet = 0; bool pick_new_inputs = true; CAmount nValueIn = 0; @@ -2667,7 +2681,7 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CWalletT // Never create dust outputs; if we would, just // add the dust to the fee. - if (IsDust(newTxOut, ::dustRelayFee)) + if (IsDust(newTxOut, discard_rate)) { nChangePosInOut = -1; nFeeRet += nChange; @@ -2747,7 +2761,7 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CWalletT // (because of reduced tx size) and so we should add a // change output. Only try this once. CAmount fee_needed_for_change = GetMinimumFee(change_prototype_size, coin_control, ::mempool, ::feeEstimator, nullptr); - CAmount minimum_value_for_change = GetDustThreshold(change_prototype_txout, ::dustRelayFee); + CAmount minimum_value_for_change = GetDustThreshold(change_prototype_txout, discard_rate); CAmount max_excess_fee = fee_needed_for_change + minimum_value_for_change; if (nFeeRet > nFeeNeeded + max_excess_fee && nChangePosInOut == -1 && nSubtractFeeFromAmount == 0 && pick_new_inputs) { pick_new_inputs = false; @@ -3788,6 +3802,9 @@ std::string CWallet::GetWalletHelpString(bool showDebug) strUsage += HelpMessageOpt("-keypool=<n>", strprintf(_("Set key pool size to <n> (default: %u)"), DEFAULT_KEYPOOL_SIZE)); strUsage += HelpMessageOpt("-fallbackfee=<amt>", strprintf(_("A fee rate (in %s/kB) that will be used when fee estimation has insufficient data (default: %s)"), CURRENCY_UNIT, FormatMoney(DEFAULT_FALLBACK_FEE))); + strUsage += HelpMessageOpt("-discardfee=<amt>", strprintf(_("The fee rate (in %s/kB) used to discard change (to fee) if it would be dust at this fee rate (default: %s) " + "Note: We will always discard up to the dust relay fee and a discard fee above that is limited by the longest target fee estimate"), + CURRENCY_UNIT, FormatMoney(DEFAULT_DISCARD_FEE))); strUsage += HelpMessageOpt("-mintxfee=<amt>", strprintf(_("Fees (in %s/kB) smaller than this are considered zero fee for transaction creation (default: %s)"), CURRENCY_UNIT, FormatMoney(DEFAULT_TRANSACTION_MINFEE))); strUsage += HelpMessageOpt("-paytxfee=<amt>", strprintf(_("Fee (in %s/kB) to add to transactions you send (default: %s)"), @@ -4113,6 +4130,16 @@ bool CWallet::ParameterInteraction() _("This is the transaction fee you may pay when fee estimates are not available.")); CWallet::fallbackFee = CFeeRate(nFeePerK); } + if (IsArgSet("-discardfee")) + { + CAmount nFeePerK = 0; + if (!ParseMoney(GetArg("-discardfee", ""), nFeePerK)) + return InitError(strprintf(_("Invalid amount for -discardfee=<amount>: '%s'"), GetArg("-discardfee", ""))); + if (nFeePerK > HIGH_TX_FEE_PER_KB) + InitWarning(AmountHighWarn("-discardfee") + " " + + _("This is the transaction fee you may discard if change is smaller than dust at this level")); + CWallet::m_discard_rate = CFeeRate(nFeePerK); + } if (IsArgSet("-paytxfee")) { CAmount nFeePerK = 0; diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h index b716e46a7d..a7fef8a802 100644 --- a/src/wallet/wallet.h +++ b/src/wallet/wallet.h @@ -45,6 +45,8 @@ static const unsigned int DEFAULT_KEYPOOL_SIZE = 100; static const CAmount DEFAULT_TRANSACTION_FEE = 0; //! -fallbackfee default static const CAmount DEFAULT_FALLBACK_FEE = 20000; +//! -m_discard_rate default +static const CAmount DEFAULT_DISCARD_FEE = 10000; //! -mintxfee default static const CAmount DEFAULT_TRANSACTION_MINFEE = 1000; //! minimum recommended increment for BIP 125 replacement txs @@ -965,6 +967,7 @@ public: static CFeeRate minTxFee; static CFeeRate fallbackFee; + static CFeeRate m_discard_rate; /** * Estimate the minimum fee considering user set parameters * and the required fee |