From e420a1b15e3be8c9d862173d9d554563405b34a7 Mon Sep 17 00:00:00 2001 From: Alex Morcos Date: Tue, 5 Jan 2016 13:11:34 -0500 Subject: [PATCH] Add sane fallback for fee estimation Add new commandline option "-fallbackfee" to use when fee estimation does not have sufficient data. --- src/init.cpp | 11 +++++++++++ src/qt/sendcoinsdialog.cpp | 6 ++++-- src/wallet/wallet.cpp | 9 +++++++++ src/wallet/wallet.h | 3 +++ 4 files changed, 27 insertions(+), 2 deletions(-) diff --git a/src/init.cpp b/src/init.cpp index c768ca75be..ba85a7972e 100644 --- a/src/init.cpp +++ b/src/init.cpp @@ -393,6 +393,8 @@ std::string HelpMessage(HelpMessageMode mode) strUsage += HelpMessageGroup(_("Wallet options:")); strUsage += HelpMessageOpt("-disablewallet", _("Do not load the wallet and disable wallet RPC calls")); strUsage += HelpMessageOpt("-keypool=", strprintf(_("Set key pool size to (default: %u)"), DEFAULT_KEYPOOL_SIZE)); + strUsage += HelpMessageOpt("-fallbackfee=", 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("-mintxfee=", 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=", strprintf(_("Fee (in %s/kB) to add to transactions you send (default: %s)"), @@ -947,6 +949,15 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler) else return InitError(strprintf(_("Invalid amount for -mintxfee=: '%s'"), mapArgs["-mintxfee"])); } + if (mapArgs.count("-fallbackfee")) + { + CAmount nFeePerK = 0; + if (!ParseMoney(mapArgs["-fallbackfee"], nFeePerK)) + return InitError(strprintf(_("Invalid amount for -fallbackfee=: '%s'"), mapArgs["-fallbackfee"])); + if (nFeePerK > nHighTransactionFeeWarning) + InitWarning(_("-fallbackfee is set very high! This is the transaction fee you may pay when fee estimates are not available.")); + CWallet::fallbackFee = CFeeRate(nFeePerK); + } if (mapArgs.count("-paytxfee")) { CAmount nFeePerK = 0; diff --git a/src/qt/sendcoinsdialog.cpp b/src/qt/sendcoinsdialog.cpp index 31c9028c4b..c834c3b564 100644 --- a/src/qt/sendcoinsdialog.cpp +++ b/src/qt/sendcoinsdialog.cpp @@ -640,13 +640,15 @@ void SendCoinsDialog::updateSmartFeeLabel() CFeeRate feeRate = mempool.estimateSmartFee(nBlocksToConfirm, &estimateFoundAtBlocks); if (feeRate <= CFeeRate(0)) // not enough data => minfee { - ui->labelSmartFee->setText(BitcoinUnits::formatWithUnit(model->getOptionsModel()->getDisplayUnit(), CWallet::GetRequiredFee(1000)) + "/kB"); + ui->labelSmartFee->setText(BitcoinUnits::formatWithUnit(model->getOptionsModel()->getDisplayUnit(), + std::max(CWallet::fallbackFee.GetFeePerK(), CWallet::GetRequiredFee(1000))) + "/kB"); ui->labelSmartFee2->show(); // (Smart fee not initialized yet. This usually takes a few blocks...) ui->labelFeeEstimation->setText(""); } else { - ui->labelSmartFee->setText(BitcoinUnits::formatWithUnit(model->getOptionsModel()->getDisplayUnit(), feeRate.GetFeePerK()) + "/kB"); + ui->labelSmartFee->setText(BitcoinUnits::formatWithUnit(model->getOptionsModel()->getDisplayUnit(), + std::max(feeRate.GetFeePerK(), CWallet::GetRequiredFee(1000))) + "/kB"); ui->labelSmartFee2->hide(); ui->labelFeeEstimation->setText(tr("Estimated to begin confirmation within %n block(s).", "", estimateFoundAtBlocks)); } diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp index 244bc37e76..581c688fc7 100644 --- a/src/wallet/wallet.cpp +++ b/src/wallet/wallet.cpp @@ -47,6 +47,12 @@ bool fSendFreeTransactions = DEFAULT_SEND_FREE_TRANSACTIONS; * Override with -mintxfee */ CFeeRate CWallet::minTxFee = CFeeRate(DEFAULT_TRANSACTION_MINFEE); +/** + * If fee estimation does not have enough data to provide estimates, use this fee instead. + * Has no effect if not using fee estimation + * Override with -fallbackfee + */ +CFeeRate CWallet::fallbackFee = CFeeRate(DEFAULT_FALLBACK_FEE); /** @defgroup mapWallet * @@ -2223,6 +2229,9 @@ CAmount CWallet::GetMinimumFee(unsigned int nTxBytes, unsigned int nConfirmTarge if (nFeeNeeded == 0) { int estimateFoundTarget = nConfirmTarget; nFeeNeeded = pool.estimateSmartFee(nConfirmTarget, &estimateFoundTarget).GetFee(nTxBytes); + // ... unless we don't have enough mempool data for estimatefee, then use fallbackFee + if (nFeeNeeded == 0) + nFeeNeeded = fallbackFee.GetFee(nTxBytes); } // prevent user from paying a fee below minRelayTxFee or minTxFee nFeeNeeded = std::max(nFeeNeeded, GetRequiredFee(nTxBytes)); diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h index 53a2b96690..ce57f4dae1 100644 --- a/src/wallet/wallet.h +++ b/src/wallet/wallet.h @@ -41,6 +41,8 @@ static const unsigned int DEFAULT_KEYPOOL_SIZE = 100; static const CAmount DEFAULT_TRANSACTION_FEE = 0; //! -paytxfee will warn if called with a higher fee than this amount (in satoshis) per KB static const CAmount nHighTransactionFeeWarning = 0.01 * COIN; +//! -fallbackfee default +static const CAmount DEFAULT_FALLBACK_FEE = 20000; //! -mintxfee default static const CAmount DEFAULT_TRANSACTION_MINFEE = 1000; //! -maxtxfee default @@ -666,6 +668,7 @@ public: bool AddAccountingEntry(const CAccountingEntry&, CWalletDB & pwalletdb); static CFeeRate minTxFee; + static CFeeRate fallbackFee; /** * Estimate the minimum fee considering user set parameters * and the required fee