Staking process: calculate the stakeable utxo only once.

furszy · furszy · commit 261bd227e5b5 · 2020-09-06T19:57:08.000-03:00
We were calculating the stakeable utxo before calling CreateNewBlock and inside the method (CreateCoinStake). Looping over the wallet's transactions map twice.
diff --git a/src/miner.cpp b/src/miner.cpp
@@ -168,13 +168,13 @@ bool CreateCoinbaseTx(CBlock* pblock, const CScript& scriptPubKeyIn, CBlockIndex
     return true;
 }
 
-bool SolveProofOfStake(CBlock* pblock, CBlockIndex* pindexPrev, CWallet* pwallet)
+bool SolveProofOfStake(CBlock* pblock, CBlockIndex* pindexPrev, CWallet* pwallet, std::vector<COutput>* availableCoins)
 {
     boost::this_thread::interruption_point();
     pblock->nBits = GetNextWorkRequired(pindexPrev, pblock);
     CMutableTransaction txCoinStake;
     int64_t nTxNewTime = 0;
-    if (!pwallet->CreateCoinStake(*pwallet, pindexPrev, pblock->nBits, txCoinStake, nTxNewTime)) {
+    if (!pwallet->CreateCoinStake(*pwallet, pindexPrev, pblock->nBits, txCoinStake, nTxNewTime, availableCoins)) {
         LogPrint(BCLog::STAKING, "%s : stake not found\n", __func__);
         return false;
     }
@@ -190,7 +190,7 @@ bool SolveProofOfStake(CBlock* pblock, CBlockIndex* pindexPrev, CWallet* pwallet
     return true;
 }
 
-CBlockTemplate* CreateNewBlock(const CScript& scriptPubKeyIn, CWallet* pwallet, bool fProofOfStake)
+CBlockTemplate* CreateNewBlock(const CScript& scriptPubKeyIn, CWallet* pwallet, bool fProofOfStake, std::vector<COutput>* availableCoins)
 {
     // Create new block
     std::unique_ptr<CBlockTemplate> pblocktemplate(new CBlockTemplate());
@@ -214,7 +214,7 @@ CBlockTemplate* CreateNewBlock(const CScript& scriptPubKeyIn, CWallet* pwallet,
     }
 
     // Depending on the tip height, try to find a coinstake who solves the block or create a coinbase tx.
-    if (!(fProofOfStake ? SolveProofOfStake(pblock, pindexPrev, pwallet)
+    if (!(fProofOfStake ? SolveProofOfStake(pblock, pindexPrev, pwallet, availableCoins)
                         : CreateCoinbaseTx(pblock, scriptPubKeyIn, pindexPrev))) {
         return nullptr;
     }
@@ -556,13 +556,13 @@ bool fGenerateBitcoins = false;
 bool fStakeableCoins = false;
 int nMintableLastCheck = 0;
 
-void CheckForCoins(CWallet* pwallet, const int minutes)
+void CheckForCoins(CWallet* pwallet, const int minutes, std::vector<COutput>* availableCoins)
 {
     //control the amount of times the client will check for mintable coins
     int nTimeNow = GetTime();
     if ((nTimeNow - nMintableLastCheck > minutes * 60)) {
         nMintableLastCheck = nTimeNow;
-        fStakeableCoins = pwallet->StakeableCoins();
+        fStakeableCoins = pwallet->StakeableCoins(availableCoins);
     }
 }
 
@@ -578,9 +578,10 @@ void BitcoinMiner(CWallet* pwallet, bool fProofOfStake)
     Optional<CReserveKey> opReservekey{nullopt};
     if (!fProofOfStake) {
         opReservekey = CReserveKey(pwallet);
-
     }
 
+    // Available UTXO set
+    std::vector<COutput> availableCoins;
     unsigned int nExtraNonce = 0;
 
     while (fGenerateBitcoins || fProofOfStake) {
@@ -597,13 +598,13 @@ void BitcoinMiner(CWallet* pwallet, bool fProofOfStake)
             }
 
             // update fStakeableCoins (5 minute check time);
-            CheckForCoins(pwallet, 5);
+            CheckForCoins(pwallet, 5, &availableCoins);
 
             while ((g_connman && g_connman->GetNodeCount(CConnman::CONNECTIONS_ALL) == 0 && Params().MiningRequiresPeers())
                     || pwallet->IsLocked() || !fStakeableCoins || masternodeSync.NotCompleted()) {
                 MilliSleep(5000);
                 // Do a separate 1 minute check here to ensure fStakeableCoins is updated
-                if (!fStakeableCoins) CheckForCoins(pwallet, 1);
+                if (!fStakeableCoins) CheckForCoins(pwallet, 1, &availableCoins);
             }
 
             //search our map of hashed blocks, see if bestblock has been hashed yet
@@ -626,7 +627,7 @@ void BitcoinMiner(CWallet* pwallet, bool fProofOfStake)
         unsigned int nTransactionsUpdatedLast = mempool.GetTransactionsUpdated();
 
         std::unique_ptr<CBlockTemplate> pblocktemplate((fProofOfStake ?
-                                                        CreateNewBlock(CScript(), pwallet, fProofOfStake) :
+                                                        CreateNewBlock(CScript(), pwallet, true, &availableCoins) :
                                                         CreateNewBlockWithKey(*opReservekey, pwallet)));
         if (!pblocktemplate.get()) continue;
         CBlock* pblock = &pblocktemplate->block;
diff --git a/src/miner.h b/src/miner.h
@@ -14,6 +14,7 @@
 class CBlock;
 class CBlockHeader;
 class CBlockIndex;
+class COutput;
 class CReserveKey;
 class CScript;
 class CWallet;
@@ -23,7 +24,7 @@ static const bool DEFAULT_PRINTPRIORITY = false;
 struct CBlockTemplate;
 
 /** Generate a new block, without valid proof-of-work */
-CBlockTemplate* CreateNewBlock(const CScript& scriptPubKeyIn, CWallet* pwallet, bool fProofOfStake);
+CBlockTemplate* CreateNewBlock(const CScript& scriptPubKeyIn, CWallet* pwallet, bool fProofOfStake, std::vector<COutput>* availableCoins = nullptr);
 /** Modify the extranonce in a block */
 void IncrementExtraNonce(CBlock* pblock, CBlockIndex* pindexPrev, unsigned int& nExtraNonce);
 /** Check mined block */
diff --git a/src/rpc/mining.cpp b/src/rpc/mining.cpp
@@ -157,10 +157,17 @@ UniValue generate(const JSONRPCRequest& request)
     UniValue blockHashes(UniValue::VARR);
     CReserveKey reservekey(pwalletMain);
     unsigned int nExtraNonce = 0;
-    while (nHeight < nHeightEnd && !ShutdownRequested())
-    {
+
+    while (nHeight < nHeightEnd && !ShutdownRequested()) {
+
+        // Get available coins
+        std::vector<COutput> availableCoins;
+        if (fPoS && !pwalletMain->StakeableCoins(&availableCoins)) {
+            throw JSONRPCError(RPC_WALLET_INSUFFICIENT_FUNDS, "No available coins to stake");
+        }
+
         std::unique_ptr<CBlockTemplate> pblocktemplate(fPoS ?
-                                                       CreateNewBlock(CScript(), pwalletMain, fPoS) :
+                                                       CreateNewBlock(CScript(), pwalletMain, true, &availableCoins) :
                                                        CreateNewBlockWithKey(reservekey, pwalletMain));
         if (!pblocktemplate.get()) break;
         CBlock *pblock = &pblocktemplate->block;
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
@@ -2724,14 +2724,10 @@ bool CWallet::CreateCoinStake(
         const CBlockIndex* pindexPrev,
         unsigned int nBits,
         CMutableTransaction& txNew,
-        int64_t& nTxNewTime)
+        int64_t& nTxNewTime,
+        std::vector<COutput>* availableCoins
+        )
 {
-    // Get the list of stakable utxos
-    std::vector<COutput> vCoins;
-    if (!StakeableCoins(&vCoins)) {
-        LogPrintf("%s: No coin available to stake.\n", __func__);
-        return false;
-    }
 
     const Consensus::Params& consensus = Params().GetConsensus();
 
@@ -2742,7 +2738,7 @@ bool CWallet::CreateCoinStake(
 
     // update staker status (hash)
     pStakerStatus->SetLastTip(pindexPrev);
-    pStakerStatus->SetLastCoins((int) vCoins.size());
+    pStakerStatus->SetLastCoins((int) availableCoins->size());
 
     // P2PKH block signatures were not accepted before v5 update.
     bool onlyP2PK = !consensus.NetworkUpgradeActive(pindexPrev->nHeight + 1, Consensus::UPGRADE_V5_DUMMY);
@@ -2752,7 +2748,7 @@ bool CWallet::CreateCoinStake(
     CScript scriptPubKeyKernel;
     bool fKernelFound = false;
     int nAttempts = 0;
-    for (const COutput &out : vCoins) {
+    for (const COutput &out : *availableCoins) {
         CPivStake stakeInput;
         stakeInput.SetPrevout((CTransaction) *out.tx, out.i);
 
diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h
@@ -567,7 +567,12 @@ class CWallet : public CCryptoKeyStore, public CValidationInterface
     };
     CWallet::CommitResult CommitTransaction(CWalletTx& wtxNew, CReserveKey& reservekey, CConnman* connman, std::string strCommand = NetMsgType::TX);
     bool AddAccountingEntry(const CAccountingEntry&, CWalletDB & pwalletdb);
-    bool CreateCoinStake(const CKeyStore& keystore, const CBlockIndex* pindexPrev, unsigned int nBits, CMutableTransaction& txNew, int64_t& nTxNewTime);
+    bool CreateCoinStake(const CKeyStore& keystore,
+                         const CBlockIndex* pindexPrev,
+                         unsigned int nBits,
+                         CMutableTransaction& txNew,
+                         int64_t& nTxNewTime,
+                         std::vector<COutput>* availableCoins);
     bool MultiSend();
     void AutoCombineDust(CConnman* connman);
 
