wallet: Move long term feerate setting to CreateTransaction

Instead of setting the long term feerate for each SelectCoinsMinConf
iteration, set it once during CreateTransaction and let it be shared
with each SelectCoinsMinConf through
coin_selection_params.m_long_term_feerate.

Does not change behavior.

Author: achow101

src/bench/coin_selection.cpp

@@ -49,7 +49,10 @@ static void CoinSelection(benchmark::Bench& bench)
     }
 
     const CoinEligibilityFilter filter_standard(1, 6, 0);
-    const CoinSelectionParams coin_selection_params(true, 34, 148, CFeeRate(0), 0, false);
+    const CoinSelectionParams coin_selection_params(/* use_bnb= */ true, /* change_output_size= */ 34,
+                                                    /* change_spend_size= */ 148, /* effective_fee= */ CFeeRate(0),
+                                                    /* long_term_feerate= */ CFeeRate(0),
+                                                    /* tx_no_inputs_size= */ 0, /* avoid_partial= */ false);
     bench.run([&] {
         std::set<CInputCoin> setCoinsRet;
         CAmount nValueRet;

src/wallet/test/coinselector_tests.cpp

@@ -35,7 +35,10 @@ static CAmount balance = 0;
 CoinEligibilityFilter filter_standard(1, 6, 0);
 CoinEligibilityFilter filter_confirmed(1, 1, 0);
 CoinEligibilityFilter filter_standard_extra(6, 6, 0);
-CoinSelectionParams coin_selection_params(false, 0, 0, CFeeRate(0), 0, false);
+CoinSelectionParams coin_selection_params(/* use_bnb= */ false, /* change_output_size= */ 0,
+                                          /* change_spend_size= */ 0, /* effective_fee= */ CFeeRate(0),
+                                          /* long_term_feerate= */ CFeeRate(0),
+                                          /* tx_no_inputs_size= */ 0, /* avoid_partial= */ false);
 
 static void add_coin(const CAmount& nValue, int nInput, std::vector<CInputCoin>& set)
 {
@@ -269,7 +272,10 @@ BOOST_AUTO_TEST_CASE(bnb_search_test)
     }
 
     // Make sure that effective value is working in SelectCoinsMinConf when BnB is used
-    CoinSelectionParams coin_selection_params_bnb(true, 0, 0, CFeeRate(3000), 0, false);
+    CoinSelectionParams coin_selection_params_bnb(/* use_bnb= */ true, /* change_output_size= */ 0,
+                                                  /* change_spend_size= */ 0, /* effective_fee= */ CFeeRate(3000),
+                                                  /* long_term_feerate= */ CFeeRate(1000),
+                                                  /* tx_no_inputs_size= */ 0, /* avoid_partial= */ false);
     CoinSet setCoinsRet;
     CAmount nValueRet;
     bool bnb_used;
@@ -639,8 +645,14 @@ BOOST_AUTO_TEST_CASE(SelectCoins_test)
         CAmount target = rand.randrange(balance - 1000) + 1000;
 
         // Perform selection
-        CoinSelectionParams coin_selection_params_knapsack(false, 34, 148, CFeeRate(0), 0, false);
-        CoinSelectionParams coin_selection_params_bnb(true, 34, 148, CFeeRate(0), 0, false);
+        CoinSelectionParams coin_selection_params_knapsack(/* use_bnb= */ false, /* change_output_size= */ 34,
+                                                           /* change_spend_size= */ 148, /* effective_fee= */ CFeeRate(0),
+                                                           /* long_term_feerate= */ CFeeRate(0),
+                                                           /* tx_no_inputs_size= */ 0, /* avoid_partial= */ false);
+        CoinSelectionParams coin_selection_params_bnb(/* use_bnb= */ true, /* change_output_size= */ 34,
+                                                      /* change_spend_size= */ 148, /* effective_fee= */ CFeeRate(0),
+                                                      /* long_term_feerate= */ CFeeRate(0),
+                                                      /* tx_no_inputs_size= */ 0, /* avoid_partial= */ false);
         CoinSet out_set;
         CAmount out_value = 0;
         bool bnb_used = false;

src/wallet/wallet.cpp

@@ -2364,20 +2364,14 @@ bool CWallet::SelectCoinsMinConf(const CAmount& nTargetValue, const CoinEligibil
     nValueRet = 0;
 
     if (coin_selection_params.use_bnb) {
-        // Get long term estimate
-        FeeCalculation feeCalc;
-        CCoinControl temp;
-        temp.m_confirm_target = 1008;
-        CFeeRate long_term_feerate = GetMinimumFeeRate(*this, temp, &feeCalc);
-
         // Get the feerate for effective value.
         // When subtracting the fee from the outputs, we want the effective feerate to be 0
         CFeeRate effective_feerate{0};
         if (!coin_selection_params.m_subtract_fee_outputs) {
             effective_feerate = coin_selection_params.effective_fee;
         }
 
-        std::vector<OutputGroup> groups = GroupOutputs(coins, !coin_selection_params.m_avoid_partial_spends, effective_feerate, long_term_feerate, eligibility_filter, true /* positive_only */);
+        std::vector<OutputGroup> groups = GroupOutputs(coins, !coin_selection_params.m_avoid_partial_spends, effective_feerate, coin_selection_params.m_long_term_feerate, eligibility_filter, true /* positive_only */);
 
         // Calculate cost of change
         CAmount cost_of_change = GetDiscardRate(*this).GetFee(coin_selection_params.change_spend_size) + coin_selection_params.effective_fee.GetFee(coin_selection_params.change_output_size);
@@ -2820,6 +2814,11 @@ bool CWallet::CreateTransactionInternal(
                 return false;
             }
 
+            // Get long term estimate
+            CCoinControl cc_temp;
+            cc_temp.m_confirm_target = chain().estimateMaxBlocks();
+            coin_selection_params.m_long_term_feerate = GetMinimumFeeRate(*this, cc_temp, nullptr);
+
             nFeeRet = 0;
             bool pick_new_inputs = true;
             CAmount nValueIn = 0;

src/wallet/wallet.h

@@ -607,16 +607,19 @@ struct CoinSelectionParams
     size_t change_output_size = 0;
     size_t change_spend_size = 0;
     CFeeRate effective_fee = CFeeRate(0);
+    CFeeRate m_long_term_feerate;
     size_t tx_noinputs_size = 0;
     //! Indicate that we are subtracting the fee from outputs
     bool m_subtract_fee_outputs = false;
     bool m_avoid_partial_spends = false;
 
-    CoinSelectionParams(bool use_bnb, size_t change_output_size, size_t change_spend_size, CFeeRate effective_fee, size_t tx_noinputs_size, bool avoid_partial) :
+    CoinSelectionParams(bool use_bnb, size_t change_output_size, size_t change_spend_size, CFeeRate effective_fee,
+                        CFeeRate long_term_feerate, size_t tx_noinputs_size, bool avoid_partial) :
         use_bnb(use_bnb),
         change_output_size(change_output_size),
         change_spend_size(change_spend_size),
         effective_fee(effective_fee),
+        m_long_term_feerate(long_term_feerate),
         tx_noinputs_size(tx_noinputs_size),
         m_avoid_partial_spends(avoid_partial)
     {}