src/bench/coin_selection.cpp

   1 // Copyright (c) 2012-2016 The Bitcoin Core developers
   2 // Distributed under the MIT software license, see the accompanying
   3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   4
   5 #include "bench.h"
   6 #include "wallet/wallet.h"
   7
   8 #include <boost/foreach.hpp>
   9 #include <set>
  10
  11 static void addCoin(const CAmount& nValue, const CWallet& wallet, std::vector<COutput>& vCoins)
  12 {
  13     int nInput = 0;
  14
  15     static int nextLockTime = 0;
  16     CMutableTransaction tx;
  17     tx.nLockTime = nextLockTime++; // so all transactions get different hashes
  18     tx.vout.resize(nInput + 1);
  19     tx.vout[nInput].nValue = nValue;
  20     CWalletTx* wtx = new CWalletTx(&wallet, MakeTransactionRef(std::move(tx)));
  21
  22     int nAge = 6 * 24;
  23     COutput output(wtx, nInput, nAge, true /* spendable */, true /* solvable */, true /* safe */);
  24     vCoins.push_back(output);
  25 }
  26
  27 // Simple benchmark for wallet coin selection. Note that it maybe be necessary
  28 // to build up more complicated scenarios in order to get meaningful
  29 // measurements of performance. From laanwj, "Wallet coin selection is probably
  30 // the hardest, as you need a wider selection of scenarios, just testing the
  31 // same one over and over isn't too useful. Generating random isn't useful
  32 // either for measurements."
  33 // (https://github.com/bitcoin/bitcoin/issues/7883#issuecomment-224807484)
  34 static void CoinSelection(benchmark::State& state)
  35 {
  36     const CWallet wallet;
  37     std::vector<COutput> vCoins;
  38     LOCK(wallet.cs_wallet);
  39
  40     while (state.KeepRunning()) {
  41         // Empty wallet.
  42         BOOST_FOREACH (COutput output, vCoins)
  43             delete output.tx;
  44         vCoins.clear();
  45
  46         // Add coins.
  47         for (int i = 0; i < 1000; i++)
  48             addCoin(1000 * COIN, wallet, vCoins);
  49         addCoin(3 * COIN, wallet, vCoins);
  50
  51         std::set<std::pair<const CWalletTx*, unsigned int> > setCoinsRet;
  52         CAmount nValueRet;
  53         bool success = wallet.SelectCoinsMinConf(1003 * COIN, 1, 6, 0, vCoins, setCoinsRet, nValueRet);
  54         assert(success);
  55         assert(nValueRet == 1003 * COIN);
  56         assert(setCoinsRet.size() == 2);
  57     }
  58 }
  59
  60 BENCHMARK(CoinSelection);