diff --git a/src/coins.h b/src/coins.h index 0d3ef88bc..8e5d0e7c2 100644 --- a/src/coins.h +++ b/src/coins.h @@ -1,319 +1,324 @@ // Copyright (c) 2009-2010 Satoshi Nakamoto // Copyright (c) 2009-2016 The Bitcoin Core developers // Distributed under the MIT software license, see the accompanying // file COPYING or http://www.opensource.org/licenses/mit-license.php. #ifndef BITCOIN_COINS_H #define BITCOIN_COINS_H #include #include #include #include #include #include #include #include #include /** * A UTXO entry. * * Serialized format: * - VARINT((coinbase ? 1 : 0) | (height << 1)) * - the non-spent CTxOut (via CTxOutCompressor) */ class Coin { //! Unspent transaction output. CTxOut out; //! Whether containing transaction was a coinbase and height at which the //! transaction was included into a block. uint32_t nHeightAndIsCoinBase; public: //! Empty constructor Coin() : nHeightAndIsCoinBase(0) {} //! Constructor from a CTxOut and height/coinbase information. Coin(CTxOut outIn, uint32_t nHeightIn, bool IsCoinbase) : out(std::move(outIn)), nHeightAndIsCoinBase((nHeightIn << 1) | IsCoinbase) {} uint32_t GetHeight() const { return nHeightAndIsCoinBase >> 1; } bool IsCoinBase() const { return nHeightAndIsCoinBase & 0x01; } bool IsSpent() const { return out.IsNull(); } CTxOut &GetTxOut() { return out; } const CTxOut &GetTxOut() const { return out; } void Clear() { out.SetNull(); nHeightAndIsCoinBase = 0; } template void Serialize(Stream &s) const { assert(!IsSpent()); ::Serialize(s, VARINT(nHeightAndIsCoinBase)); ::Serialize(s, CTxOutCompressor(REF(out))); } template void Unserialize(Stream &s) { ::Unserialize(s, VARINT(nHeightAndIsCoinBase)); ::Unserialize(s, CTxOutCompressor(out)); } size_t DynamicMemoryUsage() const { return memusage::DynamicUsage(out.scriptPubKey); } }; class SaltedOutpointHasher { private: /** Salt */ const uint64_t k0, k1; public: SaltedOutpointHasher(); /** * This *must* return size_t. With Boost 1.46 on 32-bit systems the * unordered_map will behave unpredictably if the custom hasher returns a * uint64_t, resulting in failures when syncing the chain (#4634). * Note: This information above might be outdated as the unordered map * container type has meanwhile been switched to the C++ standard library * implementation. */ size_t operator()(const COutPoint &outpoint) const { return SipHashUint256Extra(k0, k1, outpoint.GetTxId(), outpoint.GetN()); } }; struct CCoinsCacheEntry { // The actual cached data. Coin coin; uint8_t flags; enum Flags { // This cache entry is potentially different from the version in the // parent view. DIRTY = (1 << 0), // The parent view does not have this entry (or it is pruned). FRESH = (1 << 1), /* Note that FRESH is a performance optimization with which we can erase coins that are fully spent if we know we do not need to flush the changes to the parent cache. It is always safe to not mark FRESH if that condition is not guaranteed. */ }; CCoinsCacheEntry() : flags(0) {} explicit CCoinsCacheEntry(Coin coinIn) : coin(std::move(coinIn)), flags(0) {} }; typedef std::unordered_map CCoinsMap; /** Cursor for iterating over CoinsView state */ class CCoinsViewCursor { public: CCoinsViewCursor(const uint256 &hashBlockIn) : hashBlock(hashBlockIn) {} virtual ~CCoinsViewCursor() {} virtual bool GetKey(COutPoint &key) const = 0; virtual bool GetValue(Coin &coin) const = 0; virtual unsigned int GetValueSize() const = 0; virtual bool Valid() const = 0; virtual void Next() = 0; //! Get best block at the time this cursor was created const uint256 &GetBestBlock() const { return hashBlock; } private: uint256 hashBlock; }; /** Abstract view on the open txout dataset. */ class CCoinsView { public: /** * Retrieve the Coin (unspent transaction output) for a given outpoint. * Returns true only when an unspent coin was found, which is returned in * coin. When false is returned, coin's value is unspecified. */ virtual bool GetCoin(const COutPoint &outpoint, Coin &coin) const; //! Just check whether a given outpoint is unspent. virtual bool HaveCoin(const COutPoint &outpoint) const; //! Retrieve the block hash whose state this CCoinsView currently represents virtual uint256 GetBestBlock() const; //! Retrieve the range of blocks that may have been only partially written. //! If the database is in a consistent state, the result is the empty //! vector. //! Otherwise, a two-element vector is returned consisting of the new and //! the old block hash, in that order. virtual std::vector GetHeadBlocks() const; //! Do a bulk modification (multiple Coin changes + BestBlock change). //! The passed mapCoins can be modified. virtual bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock); //! Get a cursor to iterate over the whole state virtual CCoinsViewCursor *Cursor() const; //! As we use CCoinsViews polymorphically, have a virtual destructor virtual ~CCoinsView() {} //! Estimate database size (0 if not implemented) virtual size_t EstimateSize() const { return 0; } }; /** CCoinsView backed by another CCoinsView */ class CCoinsViewBacked : public CCoinsView { protected: CCoinsView *base; public: CCoinsViewBacked(CCoinsView *viewIn); bool GetCoin(const COutPoint &outpoint, Coin &coin) const override; bool HaveCoin(const COutPoint &outpoint) const override; uint256 GetBestBlock() const override; std::vector GetHeadBlocks() const override; void SetBackend(CCoinsView &viewIn); bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock) override; CCoinsViewCursor *Cursor() const override; size_t EstimateSize() const override; }; /** * CCoinsView that adds a memory cache for transactions to another CCoinsView */ class CCoinsViewCache : public CCoinsViewBacked { protected: /** * Make mutable so that we can "fill the cache" even from Get-methods * declared as "const". */ mutable uint256 hashBlock; mutable CCoinsMap cacheCoins; /* Cached dynamic memory usage for the inner Coin objects. */ mutable size_t cachedCoinsUsage; public: CCoinsViewCache(CCoinsView *baseIn); /** * By deleting the copy constructor, we prevent accidentally using it when * one intends to create a cache on top of a base cache. */ CCoinsViewCache(const CCoinsViewCache &) = delete; // Standard CCoinsView methods bool GetCoin(const COutPoint &outpoint, Coin &coin) const override; bool HaveCoin(const COutPoint &outpoint) const override; uint256 GetBestBlock() const override; void SetBestBlock(const uint256 &hashBlock); bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock) override; CCoinsViewCursor *Cursor() const override { throw std::logic_error( "CCoinsViewCache cursor iteration not supported."); } /** * Check if we have the given utxo already loaded in this cache. * The semantics are the same as HaveCoin(), but no calls to the backing * CCoinsView are made. */ bool HaveCoinInCache(const COutPoint &outpoint) const; /** - * Return a reference to a Coin in the cache, or a pruned one if not found. - * This is more efficient than GetCoin. Modifications to other cache entries - * are allowed while accessing the returned pointer. + * Return a reference to Coin in the cache, or a pruned one if not found. + * This is more efficient than GetCoin. + * + * Generally, do not hold the reference returned for more than a short + * scope. While the current implementation allows for modifications to the + * contents of the cache while holding the reference, this behavior should + * not be relied on! To be safe, best to not hold the returned reference + * through any other calls to this cache. */ const Coin &AccessCoin(const COutPoint &output) const; /** * Add a coin. Set potential_overwrite to true if a non-pruned version may * already exist. */ void AddCoin(const COutPoint &outpoint, Coin coin, bool potential_overwrite); /** * Spend a coin. Pass moveto in order to get the deleted data. * If no unspent output exists for the passed outpoint, this call has no * effect. */ bool SpendCoin(const COutPoint &outpoint, Coin *moveto = nullptr); /** * Push the modifications applied to this cache to its base. * Failure to call this method before destruction will cause the changes to * be forgotten. If false is returned, the state of this cache (and its * backing view) will be undefined. */ bool Flush(); /** * Removes the UTXO with the given outpoint from the cache, if it is not * modified. */ void Uncache(const COutPoint &outpoint); //! Calculate the size of the cache (in number of transaction outputs) unsigned int GetCacheSize() const; //! Calculate the size of the cache (in bytes) size_t DynamicMemoryUsage() const; /** * Amount of bitcoins coming in to a transaction * Note that lightweight clients may not know anything besides the hash of * previous transactions, so may not be able to calculate this. * * @param[in] tx transaction for which we are checking input total * @return Sum of value of all inputs (scriptSigs) */ Amount GetValueIn(const CTransaction &tx) const; //! Check whether all prevouts of the transaction are present in the UTXO //! set represented by this view bool HaveInputs(const CTransaction &tx) const; /** * Return priority of tx at height nHeight. Also calculate the sum of the * values of the inputs that are already in the chain. These are the inputs * that will age and increase priority as new blocks are added to the chain. */ double GetPriority(const CTransaction &tx, int nHeight, Amount &inChainInputValue) const; const CTxOut &GetOutputFor(const CTxIn &input) const; private: CCoinsMap::iterator FetchCoin(const COutPoint &outpoint) const; }; //! Utility function to add all of a transaction's outputs to a cache. // When check is false, this assumes that overwrites are only possible for // coinbase transactions. // When check is true, the underlying view may be queried to determine whether // an addition is an overwrite. // TODO: pass in a boolean to limit these possible overwrites to known // (pre-BIP34) cases. void AddCoins(CCoinsViewCache &cache, const CTransaction &tx, int nHeight, bool check = false); //! Utility function to find any unspent output with a given txid. // This function can be quite expensive because in the event of a transaction // which is not found in the cache, it can cause up to MAX_OUTPUTS_PER_BLOCK // lookups to database, so it should be used with care. const Coin &AccessByTxid(const CCoinsViewCache &cache, const TxId &txid); #endif // BITCOIN_COINS_H diff --git a/src/txmempool.cpp b/src/txmempool.cpp index 3ef5b6f3e..f83dfaa00 100644 --- a/src/txmempool.cpp +++ b/src/txmempool.cpp @@ -1,1400 +1,1398 @@ // Copyright (c) 2009-2010 Satoshi Nakamoto // Copyright (c) 2009-2016 The Bitcoin Core developers // Distributed under the MIT software license, see the accompanying // file COPYING or http://www.opensource.org/licenses/mit-license.php. #include #include #include // for GetConsensus. #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include CTxMemPoolEntry::CTxMemPoolEntry(const CTransactionRef &_tx, const Amount _nFee, int64_t _nTime, double _entryPriority, unsigned int _entryHeight, Amount _inChainInputValue, bool _spendsCoinbase, int64_t _sigOpsCount, LockPoints lp) : tx(_tx), nFee(_nFee), nTime(_nTime), entryPriority(_entryPriority), entryHeight(_entryHeight), inChainInputValue(_inChainInputValue), spendsCoinbase(_spendsCoinbase), sigOpCount(_sigOpsCount), lockPoints(lp) { nTxSize = tx->GetTotalSize(); nModSize = tx->CalculateModifiedSize(GetTxSize()); nUsageSize = RecursiveDynamicUsage(tx); nCountWithDescendants = 1; nSizeWithDescendants = GetTxSize(); nModFeesWithDescendants = nFee; Amount nValueIn = tx->GetValueOut() + nFee; assert(inChainInputValue <= nValueIn); feeDelta = Amount::zero(); nCountWithAncestors = 1; nSizeWithAncestors = GetTxSize(); nModFeesWithAncestors = nFee; nSigOpCountWithAncestors = sigOpCount; } double CTxMemPoolEntry::GetPriority(unsigned int currentHeight) const { double deltaPriority = double((currentHeight - entryHeight) * (inChainInputValue / SATOSHI)) / nModSize; double dResult = entryPriority + deltaPriority; // This should only happen if it was called with a height below entry height if (dResult < 0) { dResult = 0; } return dResult; } void CTxMemPoolEntry::UpdateFeeDelta(Amount newFeeDelta) { nModFeesWithDescendants += newFeeDelta - feeDelta; nModFeesWithAncestors += newFeeDelta - feeDelta; feeDelta = newFeeDelta; } void CTxMemPoolEntry::UpdateLockPoints(const LockPoints &lp) { lockPoints = lp; } // Update the given tx for any in-mempool descendants. // Assumes that setMemPoolChildren is correct for the given tx and all // descendants. void CTxMemPool::UpdateForDescendants(txiter updateIt, cacheMap &cachedDescendants, const std::set &setExclude) { setEntries stageEntries, setAllDescendants; stageEntries = GetMemPoolChildren(updateIt); while (!stageEntries.empty()) { const txiter cit = *stageEntries.begin(); setAllDescendants.insert(cit); stageEntries.erase(cit); const setEntries &setChildren = GetMemPoolChildren(cit); for (txiter childEntry : setChildren) { cacheMap::iterator cacheIt = cachedDescendants.find(childEntry); if (cacheIt != cachedDescendants.end()) { // We've already calculated this one, just add the entries for // this set but don't traverse again. for (txiter cacheEntry : cacheIt->second) { setAllDescendants.insert(cacheEntry); } } else if (!setAllDescendants.count(childEntry)) { // Schedule for later processing stageEntries.insert(childEntry); } } } // setAllDescendants now contains all in-mempool descendants of updateIt. // Update and add to cached descendant map int64_t modifySize = 0; int64_t modifyCount = 0; Amount modifyFee = Amount::zero(); for (txiter cit : setAllDescendants) { if (!setExclude.count(cit->GetTx().GetId())) { modifySize += cit->GetTxSize(); modifyFee += cit->GetModifiedFee(); modifyCount++; cachedDescendants[updateIt].insert(cit); // Update ancestor state for each descendant mapTx.modify(cit, update_ancestor_state(updateIt->GetTxSize(), updateIt->GetModifiedFee(), 1, updateIt->GetSigOpCount())); } } mapTx.modify(updateIt, update_descendant_state(modifySize, modifyFee, modifyCount)); } // txidsToUpdate is the set of transaction hashes from a disconnected block // which has been re-added to the mempool. For each entry, look for descendants // that are outside txidsToUpdate, and add fee/size information for such // descendants to the parent. For each such descendant, also update the ancestor // state to include the parent. void CTxMemPool::UpdateTransactionsFromBlock( const std::vector &txidsToUpdate) { LOCK(cs); // For each entry in txidsToUpdate, store the set of in-mempool, but not // in-txidsToUpdate transactions, so that we don't have to recalculate // descendants when we come across a previously seen entry. cacheMap mapMemPoolDescendantsToUpdate; // Use a set for lookups into txidsToUpdate (these entries are already // accounted for in the state of their ancestors) std::set setAlreadyIncluded(txidsToUpdate.begin(), txidsToUpdate.end()); // Iterate in reverse, so that whenever we are looking at a transaction // we are sure that all in-mempool descendants have already been processed. // This maximizes the benefit of the descendant cache and guarantees that // setMemPoolChildren will be updated, an assumption made in // UpdateForDescendants. for (const TxId &txid : reverse_iterate(txidsToUpdate)) { // we cache the in-mempool children to avoid duplicate updates setEntries setChildren; // calculate children from mapNextTx txiter it = mapTx.find(txid); if (it == mapTx.end()) { continue; } auto iter = mapNextTx.lower_bound(COutPoint(txid, 0)); // First calculate the children, and update setMemPoolChildren to // include them, and update their setMemPoolParents to include this tx. for (; iter != mapNextTx.end() && iter->first->GetTxId() == txid; ++iter) { const TxId &childTxId = iter->second->GetId(); txiter childIter = mapTx.find(childTxId); assert(childIter != mapTx.end()); // We can skip updating entries we've encountered before or that are // in the block (which are already accounted for). if (setChildren.insert(childIter).second && !setAlreadyIncluded.count(childTxId)) { UpdateChild(it, childIter, true); UpdateParent(childIter, it, true); } } UpdateForDescendants(it, mapMemPoolDescendantsToUpdate, setAlreadyIncluded); } } bool CTxMemPool::CalculateMemPoolAncestors( const CTxMemPoolEntry &entry, setEntries &setAncestors, uint64_t limitAncestorCount, uint64_t limitAncestorSize, uint64_t limitDescendantCount, uint64_t limitDescendantSize, std::string &errString, bool fSearchForParents /* = true */) const { LOCK(cs); setEntries parentHashes; const CTransaction &tx = entry.GetTx(); if (fSearchForParents) { // Get parents of this transaction that are in the mempool // GetMemPoolParents() is only valid for entries in the mempool, so we // iterate mapTx to find parents. for (const CTxIn &in : tx.vin) { txiter piter = mapTx.find(in.prevout.GetTxId()); if (piter == mapTx.end()) { continue; } parentHashes.insert(piter); if (parentHashes.size() + 1 > limitAncestorCount) { errString = strprintf("too many unconfirmed parents [limit: %u]", limitAncestorCount); return false; } } } else { // If we're not searching for parents, we require this to be an entry in // the mempool already. txiter it = mapTx.iterator_to(entry); parentHashes = GetMemPoolParents(it); } size_t totalSizeWithAncestors = entry.GetTxSize(); while (!parentHashes.empty()) { txiter stageit = *parentHashes.begin(); setAncestors.insert(stageit); parentHashes.erase(stageit); totalSizeWithAncestors += stageit->GetTxSize(); if (stageit->GetSizeWithDescendants() + entry.GetTxSize() > limitDescendantSize) { errString = strprintf( "exceeds descendant size limit for tx %s [limit: %u]", stageit->GetTx().GetId().ToString(), limitDescendantSize); return false; } if (stageit->GetCountWithDescendants() + 1 > limitDescendantCount) { errString = strprintf("too many descendants for tx %s [limit: %u]", stageit->GetTx().GetId().ToString(), limitDescendantCount); return false; } if (totalSizeWithAncestors > limitAncestorSize) { errString = strprintf("exceeds ancestor size limit [limit: %u]", limitAncestorSize); return false; } const setEntries &setMemPoolParents = GetMemPoolParents(stageit); for (const txiter &phash : setMemPoolParents) { // If this is a new ancestor, add it. if (setAncestors.count(phash) == 0) { parentHashes.insert(phash); } if (parentHashes.size() + setAncestors.size() + 1 > limitAncestorCount) { errString = strprintf("too many unconfirmed ancestors [limit: %u]", limitAncestorCount); return false; } } } return true; } void CTxMemPool::UpdateAncestorsOf(bool add, txiter it, setEntries &setAncestors) { setEntries parentIters = GetMemPoolParents(it); // add or remove this tx as a child of each parent for (txiter piter : parentIters) { UpdateChild(piter, it, add); } const int64_t updateCount = (add ? 1 : -1); const int64_t updateSize = updateCount * it->GetTxSize(); const Amount updateFee = updateCount * it->GetModifiedFee(); for (txiter ancestorIt : setAncestors) { mapTx.modify(ancestorIt, update_descendant_state(updateSize, updateFee, updateCount)); } } void CTxMemPool::UpdateEntryForAncestors(txiter it, const setEntries &setAncestors) { int64_t updateCount = setAncestors.size(); int64_t updateSize = 0; int64_t updateSigOpsCount = 0; Amount updateFee = Amount::zero(); for (txiter ancestorIt : setAncestors) { updateSize += ancestorIt->GetTxSize(); updateFee += ancestorIt->GetModifiedFee(); updateSigOpsCount += ancestorIt->GetSigOpCount(); } mapTx.modify(it, update_ancestor_state(updateSize, updateFee, updateCount, updateSigOpsCount)); } void CTxMemPool::UpdateChildrenForRemoval(txiter it) { const setEntries &setMemPoolChildren = GetMemPoolChildren(it); for (txiter updateIt : setMemPoolChildren) { UpdateParent(updateIt, it, false); } } void CTxMemPool::UpdateForRemoveFromMempool(const setEntries &entriesToRemove, bool updateDescendants) { // For each entry, walk back all ancestors and decrement size associated // with this transaction. const uint64_t nNoLimit = std::numeric_limits::max(); if (updateDescendants) { // updateDescendants should be true whenever we're not recursively // removing a tx and all its descendants, eg when a transaction is // confirmed in a block. Here we only update statistics and not data in // mapLinks (which we need to preserve until we're finished with all // operations that need to traverse the mempool). for (txiter removeIt : entriesToRemove) { setEntries setDescendants; CalculateDescendants(removeIt, setDescendants); setDescendants.erase(removeIt); // don't update state for self int64_t modifySize = -int64_t(removeIt->GetTxSize()); Amount modifyFee = -1 * removeIt->GetModifiedFee(); int modifySigOps = -removeIt->GetSigOpCount(); for (txiter dit : setDescendants) { mapTx.modify(dit, update_ancestor_state(modifySize, modifyFee, -1, modifySigOps)); } } } for (txiter removeIt : entriesToRemove) { setEntries setAncestors; const CTxMemPoolEntry &entry = *removeIt; std::string dummy; // Since this is a tx that is already in the mempool, we can call CMPA // with fSearchForParents = false. If the mempool is in a consistent // state, then using true or false should both be correct, though false // should be a bit faster. // However, if we happen to be in the middle of processing a reorg, then // the mempool can be in an inconsistent state. In this case, the set of // ancestors reachable via mapLinks will be the same as the set of // ancestors whose packages include this transaction, because when we // add a new transaction to the mempool in addUnchecked(), we assume it // has no children, and in the case of a reorg where that assumption is // false, the in-mempool children aren't linked to the in-block tx's // until UpdateTransactionsFromBlock() is called. So if we're being // called during a reorg, ie before UpdateTransactionsFromBlock() has // been called, then mapLinks[] will differ from the set of mempool // parents we'd calculate by searching, and it's important that we use // the mapLinks[] notion of ancestor transactions as the set of things // to update for removal. CalculateMemPoolAncestors(entry, setAncestors, nNoLimit, nNoLimit, nNoLimit, nNoLimit, dummy, false); // Note that UpdateAncestorsOf severs the child links that point to // removeIt in the entries for the parents of removeIt. UpdateAncestorsOf(false, removeIt, setAncestors); } // After updating all the ancestor sizes, we can now sever the link between // each transaction being removed and any mempool children (ie, update // setMemPoolParents for each direct child of a transaction being removed). for (txiter removeIt : entriesToRemove) { UpdateChildrenForRemoval(removeIt); } } void CTxMemPoolEntry::UpdateDescendantState(int64_t modifySize, Amount modifyFee, int64_t modifyCount) { nSizeWithDescendants += modifySize; assert(int64_t(nSizeWithDescendants) > 0); nModFeesWithDescendants += modifyFee; nCountWithDescendants += modifyCount; assert(int64_t(nCountWithDescendants) > 0); } void CTxMemPoolEntry::UpdateAncestorState(int64_t modifySize, Amount modifyFee, int64_t modifyCount, int modifySigOps) { nSizeWithAncestors += modifySize; assert(int64_t(nSizeWithAncestors) > 0); nModFeesWithAncestors += modifyFee; nCountWithAncestors += modifyCount; assert(int64_t(nCountWithAncestors) > 0); nSigOpCountWithAncestors += modifySigOps; assert(int(nSigOpCountWithAncestors) >= 0); } CTxMemPool::CTxMemPool() : nTransactionsUpdated(0) { // lock free clear _clear(); // Sanity checks off by default for performance, because otherwise accepting // transactions becomes O(N^2) where N is the number of transactions in the // pool nCheckFrequency = 0; } CTxMemPool::~CTxMemPool() {} bool CTxMemPool::isSpent(const COutPoint &outpoint) const { LOCK(cs); return mapNextTx.count(outpoint); } unsigned int CTxMemPool::GetTransactionsUpdated() const { LOCK(cs); return nTransactionsUpdated; } void CTxMemPool::AddTransactionsUpdated(unsigned int n) { LOCK(cs); nTransactionsUpdated += n; } bool CTxMemPool::addUnchecked(const uint256 &hash, const CTxMemPoolEntry &entry, setEntries &setAncestors) { NotifyEntryAdded(entry.GetSharedTx()); // Add to memory pool without checking anything. // Used by AcceptToMemoryPool(), which DOES do all the appropriate checks. LOCK(cs); indexed_transaction_set::iterator newit = mapTx.insert(entry).first; mapLinks.insert(make_pair(newit, TxLinks())); // Update transaction for any feeDelta created by PrioritiseTransaction // TODO: refactor so that the fee delta is calculated before inserting into // mapTx. std::map::const_iterator pos = mapDeltas.find(hash); if (pos != mapDeltas.end()) { const TXModifier &deltas = pos->second; if (deltas.second != Amount::zero()) { mapTx.modify(newit, update_fee_delta(deltas.second)); } } // Update cachedInnerUsage to include contained transaction's usage. // (When we update the entry for in-mempool parents, memory usage will be // further updated.) cachedInnerUsage += entry.DynamicMemoryUsage(); const CTransaction &tx = newit->GetTx(); std::set setParentTransactions; for (const CTxIn &in : tx.vin) { mapNextTx.insert(std::make_pair(&in.prevout, &tx)); setParentTransactions.insert(in.prevout.GetTxId()); } // Don't bother worrying about child transactions of this one. Normal case // of a new transaction arriving is that there can't be any children, // because such children would be orphans. An exception to that is if a // transaction enters that used to be in a block. In that case, our // disconnect block logic will call UpdateTransactionsFromBlock to clean up // the mess we're leaving here. // Update ancestors with information about this tx for (const uint256 &phash : setParentTransactions) { txiter pit = mapTx.find(phash); if (pit != mapTx.end()) { UpdateParent(newit, pit, true); } } UpdateAncestorsOf(true, newit, setAncestors); UpdateEntryForAncestors(newit, setAncestors); nTransactionsUpdated++; totalTxSize += entry.GetTxSize(); vTxHashes.emplace_back(tx.GetHash(), newit); newit->vTxHashesIdx = vTxHashes.size() - 1; return true; } void CTxMemPool::removeUnchecked(txiter it, MemPoolRemovalReason reason) { NotifyEntryRemoved(it->GetSharedTx(), reason); for (const CTxIn &txin : it->GetTx().vin) { mapNextTx.erase(txin.prevout); } if (vTxHashes.size() > 1) { vTxHashes[it->vTxHashesIdx] = std::move(vTxHashes.back()); vTxHashes[it->vTxHashesIdx].second->vTxHashesIdx = it->vTxHashesIdx; vTxHashes.pop_back(); if (vTxHashes.size() * 2 < vTxHashes.capacity()) { vTxHashes.shrink_to_fit(); } } else { vTxHashes.clear(); } totalTxSize -= it->GetTxSize(); cachedInnerUsage -= it->DynamicMemoryUsage(); cachedInnerUsage -= memusage::DynamicUsage(mapLinks[it].parents) + memusage::DynamicUsage(mapLinks[it].children); mapLinks.erase(it); mapTx.erase(it); nTransactionsUpdated++; } // Calculates descendants of entry that are not already in setDescendants, and // adds to setDescendants. Assumes entryit is already a tx in the mempool and // setMemPoolChildren is correct for tx and all descendants. Also assumes that // if an entry is in setDescendants already, then all in-mempool descendants of // it are already in setDescendants as well, so that we can save time by not // iterating over those entries. void CTxMemPool::CalculateDescendants(txiter entryit, setEntries &setDescendants) const { setEntries stage; if (setDescendants.count(entryit) == 0) { stage.insert(entryit); } // Traverse down the children of entry, only adding children that are not // accounted for in setDescendants already (because those children have // either already been walked, or will be walked in this iteration). while (!stage.empty()) { txiter it = *stage.begin(); setDescendants.insert(it); stage.erase(it); const setEntries &setChildren = GetMemPoolChildren(it); for (const txiter &childiter : setChildren) { if (!setDescendants.count(childiter)) { stage.insert(childiter); } } } } void CTxMemPool::removeRecursive(const CTransaction &origTx, MemPoolRemovalReason reason) { // Remove transaction from memory pool. LOCK(cs); setEntries txToRemove; txiter origit = mapTx.find(origTx.GetId()); if (origit != mapTx.end()) { txToRemove.insert(origit); } else { // When recursively removing but origTx isn't in the mempool be sure to // remove any children that are in the pool. This can happen during // chain re-orgs if origTx isn't re-accepted into the mempool for any // reason. for (size_t i = 0; i < origTx.vout.size(); i++) { auto it = mapNextTx.find(COutPoint(origTx.GetId(), i)); if (it == mapNextTx.end()) { continue; } txiter nextit = mapTx.find(it->second->GetId()); assert(nextit != mapTx.end()); txToRemove.insert(nextit); } } setEntries setAllRemoves; for (txiter it : txToRemove) { CalculateDescendants(it, setAllRemoves); } RemoveStaged(setAllRemoves, false, reason); } void CTxMemPool::removeForReorg(const Config &config, const CCoinsViewCache *pcoins, unsigned int nMemPoolHeight, int flags) { // Remove transactions spending a coinbase which are now immature and // no-longer-final transactions. LOCK(cs); setEntries txToRemove; for (indexed_transaction_set::const_iterator it = mapTx.begin(); it != mapTx.end(); it++) { const CTransaction &tx = it->GetTx(); LockPoints lp = it->GetLockPoints(); bool validLP = TestLockPointValidity(&lp); CValidationState state; if (!ContextualCheckTransactionForCurrentBlock(config, tx, state, flags) || !CheckSequenceLocks(tx, flags, &lp, validLP)) { // Note if CheckSequenceLocks fails the LockPoints may still be // invalid. So it's critical that we remove the tx and not depend on // the LockPoints. txToRemove.insert(it); } else if (it->GetSpendsCoinbase()) { for (const CTxIn &txin : tx.vin) { indexed_transaction_set::const_iterator it2 = mapTx.find(txin.prevout.GetTxId()); if (it2 != mapTx.end()) { continue; } const Coin &coin = pcoins->AccessCoin(txin.prevout); if (nCheckFrequency != 0) { assert(!coin.IsSpent()); } if (coin.IsSpent() || (coin.IsCoinBase() && int64_t(nMemPoolHeight) - coin.GetHeight() < COINBASE_MATURITY)) { txToRemove.insert(it); break; } } } if (!validLP) { mapTx.modify(it, update_lock_points(lp)); } } setEntries setAllRemoves; for (txiter it : txToRemove) { CalculateDescendants(it, setAllRemoves); } RemoveStaged(setAllRemoves, false, MemPoolRemovalReason::REORG); } void CTxMemPool::removeConflicts(const CTransaction &tx) { // Remove transactions which depend on inputs of tx, recursively LOCK(cs); for (const CTxIn &txin : tx.vin) { auto it = mapNextTx.find(txin.prevout); if (it != mapNextTx.end()) { const CTransaction &txConflict = *it->second; if (txConflict != tx) { ClearPrioritisation(txConflict.GetId()); removeRecursive(txConflict, MemPoolRemovalReason::CONFLICT); } } } } /** * Called when a block is connected. Removes from mempool and updates the miner * fee estimator. */ void CTxMemPool::removeForBlock(const std::vector &vtx, unsigned int nBlockHeight) { LOCK(cs); DisconnectedBlockTransactions disconnectpool; disconnectpool.addForBlock(vtx); std::vector entries; for (const CTransactionRef &tx : reverse_iterate(disconnectpool.GetQueuedTx().get())) { uint256 txid = tx->GetId(); indexed_transaction_set::iterator i = mapTx.find(txid); if (i != mapTx.end()) { entries.push_back(&*i); } } for (const CTransactionRef &tx : reverse_iterate(disconnectpool.GetQueuedTx().get())) { txiter it = mapTx.find(tx->GetId()); if (it != mapTx.end()) { setEntries stage; stage.insert(it); RemoveStaged(stage, true, MemPoolRemovalReason::BLOCK); } removeConflicts(*tx); ClearPrioritisation(tx->GetId()); } disconnectpool.clear(); lastRollingFeeUpdate = GetTime(); blockSinceLastRollingFeeBump = true; } void CTxMemPool::_clear() { mapLinks.clear(); mapTx.clear(); mapNextTx.clear(); vTxHashes.clear(); totalTxSize = 0; cachedInnerUsage = 0; lastRollingFeeUpdate = GetTime(); blockSinceLastRollingFeeBump = false; rollingMinimumFeeRate = 0; ++nTransactionsUpdated; } void CTxMemPool::clear() { LOCK(cs); _clear(); } static void CheckInputsAndUpdateCoins(const CTransaction &tx, CCoinsViewCache &mempoolDuplicate, const int64_t spendheight) { CValidationState state; Amount txfee = Amount::zero(); bool fCheckResult = tx.IsCoinBase() || Consensus::CheckTxInputs(tx, state, mempoolDuplicate, spendheight, txfee); assert(fCheckResult); UpdateCoins(mempoolDuplicate, tx, 1000000); } void CTxMemPool::check(const CCoinsViewCache *pcoins) const { LOCK(cs); if (nCheckFrequency == 0) { return; } if (GetRand(std::numeric_limits::max()) >= nCheckFrequency) { return; } LogPrint(BCLog::MEMPOOL, "Checking mempool with %u transactions and %u inputs\n", (unsigned int)mapTx.size(), (unsigned int)mapNextTx.size()); uint64_t checkTotal = 0; uint64_t innerUsage = 0; CCoinsViewCache mempoolDuplicate(const_cast(pcoins)); const int64_t spendheight = GetSpendHeight(mempoolDuplicate); std::list waitingOnDependants; for (indexed_transaction_set::const_iterator it = mapTx.begin(); it != mapTx.end(); it++) { unsigned int i = 0; checkTotal += it->GetTxSize(); innerUsage += it->DynamicMemoryUsage(); const CTransaction &tx = it->GetTx(); txlinksMap::const_iterator linksiter = mapLinks.find(it); assert(linksiter != mapLinks.end()); const TxLinks &links = linksiter->second; innerUsage += memusage::DynamicUsage(links.parents) + memusage::DynamicUsage(links.children); bool fDependsWait = false; setEntries setParentCheck; int64_t parentSizes = 0; int64_t parentSigOpCount = 0; for (const CTxIn &txin : tx.vin) { // Check that every mempool transaction's inputs refer to available // coins, or other mempool tx's. indexed_transaction_set::const_iterator it2 = mapTx.find(txin.prevout.GetTxId()); if (it2 != mapTx.end()) { const CTransaction &tx2 = it2->GetTx(); assert(tx2.vout.size() > txin.prevout.GetN() && !tx2.vout[txin.prevout.GetN()].IsNull()); fDependsWait = true; if (setParentCheck.insert(it2).second) { parentSizes += it2->GetTxSize(); parentSigOpCount += it2->GetSigOpCount(); } } else { assert(pcoins->HaveCoin(txin.prevout)); } // Check whether its inputs are marked in mapNextTx. auto it3 = mapNextTx.find(txin.prevout); assert(it3 != mapNextTx.end()); assert(it3->first == &txin.prevout); assert(it3->second == &tx); i++; } assert(setParentCheck == GetMemPoolParents(it)); // Verify ancestor state is correct. setEntries setAncestors; uint64_t nNoLimit = std::numeric_limits::max(); std::string dummy; CalculateMemPoolAncestors(*it, setAncestors, nNoLimit, nNoLimit, nNoLimit, nNoLimit, dummy); uint64_t nCountCheck = setAncestors.size() + 1; uint64_t nSizeCheck = it->GetTxSize(); Amount nFeesCheck = it->GetModifiedFee(); int64_t nSigOpCheck = it->GetSigOpCount(); for (txiter ancestorIt : setAncestors) { nSizeCheck += ancestorIt->GetTxSize(); nFeesCheck += ancestorIt->GetModifiedFee(); nSigOpCheck += ancestorIt->GetSigOpCount(); } assert(it->GetCountWithAncestors() == nCountCheck); assert(it->GetSizeWithAncestors() == nSizeCheck); assert(it->GetSigOpCountWithAncestors() == nSigOpCheck); assert(it->GetModFeesWithAncestors() == nFeesCheck); // Check children against mapNextTx CTxMemPool::setEntries setChildrenCheck; auto iter = mapNextTx.lower_bound(COutPoint(it->GetTx().GetId(), 0)); int64_t childSizes = 0; for (; iter != mapNextTx.end() && iter->first->GetTxId() == it->GetTx().GetId(); ++iter) { txiter childit = mapTx.find(iter->second->GetId()); // mapNextTx points to in-mempool transactions assert(childit != mapTx.end()); if (setChildrenCheck.insert(childit).second) { childSizes += childit->GetTxSize(); } } assert(setChildrenCheck == GetMemPoolChildren(it)); // Also check to make sure size is greater than sum with immediate // children. Just a sanity check, not definitive that this calc is // correct... assert(it->GetSizeWithDescendants() >= childSizes + it->GetTxSize()); if (fDependsWait) { waitingOnDependants.push_back(&(*it)); } else { CheckInputsAndUpdateCoins(tx, mempoolDuplicate, spendheight); } } unsigned int stepsSinceLastRemove = 0; while (!waitingOnDependants.empty()) { const CTxMemPoolEntry *entry = waitingOnDependants.front(); waitingOnDependants.pop_front(); CValidationState state; if (!mempoolDuplicate.HaveInputs(entry->GetTx())) { waitingOnDependants.push_back(entry); stepsSinceLastRemove++; assert(stepsSinceLastRemove < waitingOnDependants.size()); } else { CheckInputsAndUpdateCoins(entry->GetTx(), mempoolDuplicate, spendheight); stepsSinceLastRemove = 0; } } for (auto it = mapNextTx.cbegin(); it != mapNextTx.cend(); it++) { uint256 txid = it->second->GetId(); indexed_transaction_set::const_iterator it2 = mapTx.find(txid); const CTransaction &tx = it2->GetTx(); assert(it2 != mapTx.end()); assert(&tx == it->second); } assert(totalTxSize == checkTotal); assert(innerUsage == cachedInnerUsage); } bool CTxMemPool::CompareDepthAndScore(const uint256 &hasha, const uint256 &hashb) { LOCK(cs); indexed_transaction_set::const_iterator i = mapTx.find(hasha); if (i == mapTx.end()) { return false; } indexed_transaction_set::const_iterator j = mapTx.find(hashb); if (j == mapTx.end()) { return true; } uint64_t counta = i->GetCountWithAncestors(); uint64_t countb = j->GetCountWithAncestors(); if (counta == countb) { return CompareTxMemPoolEntryByScore()(*i, *j); } return counta < countb; } namespace { class DepthAndScoreComparator { public: bool operator()(const CTxMemPool::indexed_transaction_set::const_iterator &a, const CTxMemPool::indexed_transaction_set::const_iterator &b) { uint64_t counta = a->GetCountWithAncestors(); uint64_t countb = b->GetCountWithAncestors(); if (counta == countb) { return CompareTxMemPoolEntryByScore()(*a, *b); } return counta < countb; } }; } // namespace std::vector CTxMemPool::GetSortedDepthAndScore() const { std::vector iters; AssertLockHeld(cs); iters.reserve(mapTx.size()); for (indexed_transaction_set::iterator mi = mapTx.begin(); mi != mapTx.end(); ++mi) { iters.push_back(mi); } std::sort(iters.begin(), iters.end(), DepthAndScoreComparator()); return iters; } void CTxMemPool::queryHashes(std::vector &vtxid) { LOCK(cs); auto iters = GetSortedDepthAndScore(); vtxid.clear(); vtxid.reserve(mapTx.size()); for (auto it : iters) { vtxid.push_back(it->GetTx().GetId()); } } static TxMempoolInfo GetInfo(CTxMemPool::indexed_transaction_set::const_iterator it) { return TxMempoolInfo{it->GetSharedTx(), it->GetTime(), CFeeRate(it->GetFee(), it->GetTxSize()), it->GetModifiedFee() - it->GetFee()}; } std::vector CTxMemPool::infoAll() const { LOCK(cs); auto iters = GetSortedDepthAndScore(); std::vector ret; ret.reserve(mapTx.size()); for (auto it : iters) { ret.push_back(GetInfo(it)); } return ret; } CTransactionRef CTxMemPool::get(const uint256 &txid) const { LOCK(cs); indexed_transaction_set::const_iterator i = mapTx.find(txid); if (i == mapTx.end()) { return nullptr; } return i->GetSharedTx(); } TxMempoolInfo CTxMemPool::info(const uint256 &txid) const { LOCK(cs); indexed_transaction_set::const_iterator i = mapTx.find(txid); if (i == mapTx.end()) { return TxMempoolInfo(); } return GetInfo(i); } CFeeRate CTxMemPool::estimateFee() const { LOCK(cs); uint64_t maxMempoolSize = gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000; // minerPolicy uses recent blocks to figure out a reasonable fee. This // may disagree with the rollingMinimumFeerate under certain scenarios // where the mempool increases rapidly, or blocks are being mined which // do not contain propagated transactions. return std::max(::minRelayTxFee, GetMinFee(maxMempoolSize)); } void CTxMemPool::PrioritiseTransaction(const uint256 &hash, double dPriorityDelta, const Amount nFeeDelta) { { LOCK(cs); TXModifier &deltas = mapDeltas[hash]; deltas.first += dPriorityDelta; deltas.second += nFeeDelta; txiter it = mapTx.find(hash); if (it != mapTx.end()) { mapTx.modify(it, update_fee_delta(deltas.second)); // Now update all ancestors' modified fees with descendants setEntries setAncestors; uint64_t nNoLimit = std::numeric_limits::max(); std::string dummy; CalculateMemPoolAncestors(*it, setAncestors, nNoLimit, nNoLimit, nNoLimit, nNoLimit, dummy, false); for (txiter ancestorIt : setAncestors) { mapTx.modify(ancestorIt, update_descendant_state(0, nFeeDelta, 0)); } // Now update all descendants' modified fees with ancestors setEntries setDescendants; CalculateDescendants(it, setDescendants); setDescendants.erase(it); for (txiter descendantIt : setDescendants) { mapTx.modify(descendantIt, update_ancestor_state(0, nFeeDelta, 0, 0)); } ++nTransactionsUpdated; } } LogPrintf("PrioritiseTransaction: %s priority += %f, fee += %d\n", hash.ToString(), dPriorityDelta, FormatMoney(nFeeDelta)); } void CTxMemPool::ApplyDeltas(const uint256 hash, double &dPriorityDelta, Amount &nFeeDelta) const { LOCK(cs); std::map::const_iterator pos = mapDeltas.find(hash); if (pos == mapDeltas.end()) { return; } const TXModifier &deltas = pos->second; dPriorityDelta += deltas.first; nFeeDelta += deltas.second; } void CTxMemPool::ClearPrioritisation(const uint256 hash) { LOCK(cs); mapDeltas.erase(hash); } bool CTxMemPool::HasNoInputsOf(const CTransaction &tx) const { for (const CTxIn &in : tx.vin) { if (exists(in.prevout.GetTxId())) { return false; } } return true; } CCoinsViewMemPool::CCoinsViewMemPool(CCoinsView *baseIn, const CTxMemPool &mempoolIn) : CCoinsViewBacked(baseIn), mempool(mempoolIn) {} bool CCoinsViewMemPool::GetCoin(const COutPoint &outpoint, Coin &coin) const { // If an entry in the mempool exists, always return that one, as it's // guaranteed to never conflict with the underlying cache, and it cannot // have pruned entries (as it contains full) transactions. First checking // the underlying cache risks returning a pruned entry instead. CTransactionRef ptx = mempool.get(outpoint.GetTxId()); if (ptx) { if (outpoint.GetN() < ptx->vout.size()) { coin = Coin(ptx->vout[outpoint.GetN()], MEMPOOL_HEIGHT, false); return true; } return false; } return base->GetCoin(outpoint, coin); } size_t CTxMemPool::DynamicMemoryUsage() const { LOCK(cs); // Estimate the overhead of mapTx to be 12 pointers + an allocation, as no // exact formula for boost::multi_index_contained is implemented. return memusage::MallocUsage(sizeof(CTxMemPoolEntry) + 12 * sizeof(void *)) * mapTx.size() + memusage::DynamicUsage(mapNextTx) + memusage::DynamicUsage(mapDeltas) + memusage::DynamicUsage(mapLinks) + memusage::DynamicUsage(vTxHashes) + cachedInnerUsage; } void CTxMemPool::RemoveStaged(setEntries &stage, bool updateDescendants, MemPoolRemovalReason reason) { AssertLockHeld(cs); UpdateForRemoveFromMempool(stage, updateDescendants); for (const txiter &it : stage) { removeUnchecked(it, reason); } } int CTxMemPool::Expire(int64_t time) { LOCK(cs); indexed_transaction_set::index::type::iterator it = mapTx.get().begin(); setEntries toremove; while (it != mapTx.get().end() && it->GetTime() < time) { toremove.insert(mapTx.project<0>(it)); it++; } setEntries stage; for (txiter removeit : toremove) { CalculateDescendants(removeit, stage); } RemoveStaged(stage, false, MemPoolRemovalReason::EXPIRY); return stage.size(); } void CTxMemPool::LimitSize(size_t limit, unsigned long age) { int expired = Expire(GetTime() - age); if (expired != 0) { LogPrint(BCLog::MEMPOOL, "Expired %i transactions from the memory pool\n", expired); } std::vector vNoSpendsRemaining; TrimToSize(limit, &vNoSpendsRemaining); for (const COutPoint &removed : vNoSpendsRemaining) { pcoinsTip->Uncache(removed); } } bool CTxMemPool::addUnchecked(const uint256 &hash, const CTxMemPoolEntry &entry) { LOCK(cs); setEntries setAncestors; uint64_t nNoLimit = std::numeric_limits::max(); std::string dummy; CalculateMemPoolAncestors(entry, setAncestors, nNoLimit, nNoLimit, nNoLimit, nNoLimit, dummy); return addUnchecked(hash, entry, setAncestors); } void CTxMemPool::UpdateChild(txiter entry, txiter child, bool add) { setEntries s; if (add && mapLinks[entry].children.insert(child).second) { cachedInnerUsage += memusage::IncrementalDynamicUsage(s); } else if (!add && mapLinks[entry].children.erase(child)) { cachedInnerUsage -= memusage::IncrementalDynamicUsage(s); } } void CTxMemPool::UpdateParent(txiter entry, txiter parent, bool add) { setEntries s; if (add && mapLinks[entry].parents.insert(parent).second) { cachedInnerUsage += memusage::IncrementalDynamicUsage(s); } else if (!add && mapLinks[entry].parents.erase(parent)) { cachedInnerUsage -= memusage::IncrementalDynamicUsage(s); } } const CTxMemPool::setEntries & CTxMemPool::GetMemPoolParents(txiter entry) const { assert(entry != mapTx.end()); txlinksMap::const_iterator it = mapLinks.find(entry); assert(it != mapLinks.end()); return it->second.parents; } const CTxMemPool::setEntries & CTxMemPool::GetMemPoolChildren(txiter entry) const { assert(entry != mapTx.end()); txlinksMap::const_iterator it = mapLinks.find(entry); assert(it != mapLinks.end()); return it->second.children; } CFeeRate CTxMemPool::GetMinFee(size_t sizelimit) const { LOCK(cs); if (!blockSinceLastRollingFeeBump || rollingMinimumFeeRate == 0) { return CFeeRate(int64_t(ceill(rollingMinimumFeeRate)) * SATOSHI); } int64_t time = GetTime(); if (time > lastRollingFeeUpdate + 10) { double halflife = ROLLING_FEE_HALFLIFE; if (DynamicMemoryUsage() < sizelimit / 4) { halflife /= 4; } else if (DynamicMemoryUsage() < sizelimit / 2) { halflife /= 2; } rollingMinimumFeeRate = rollingMinimumFeeRate / pow(2.0, (time - lastRollingFeeUpdate) / halflife); lastRollingFeeUpdate = time; } return CFeeRate(int64_t(ceill(rollingMinimumFeeRate)) * SATOSHI); } void CTxMemPool::trackPackageRemoved(const CFeeRate &rate) { AssertLockHeld(cs); if ((rate.GetFeePerK() / SATOSHI) > rollingMinimumFeeRate) { rollingMinimumFeeRate = rate.GetFeePerK() / SATOSHI; blockSinceLastRollingFeeBump = false; } } void CTxMemPool::TrimToSize(size_t sizelimit, std::vector *pvNoSpendsRemaining) { LOCK(cs); unsigned nTxnRemoved = 0; CFeeRate maxFeeRateRemoved(Amount::zero()); while (!mapTx.empty() && DynamicMemoryUsage() > sizelimit) { indexed_transaction_set::index::type::iterator it = mapTx.get().begin(); // We set the new mempool min fee to the feerate of the removed set, // plus the "minimum reasonable fee rate" (ie some value under which we // consider txn to have 0 fee). This way, we don't allow txn to enter // mempool with feerate equal to txn which were removed with no block in // between. CFeeRate removed(it->GetModFeesWithDescendants(), it->GetSizeWithDescendants()); removed += MEMPOOL_FULL_FEE_INCREMENT; trackPackageRemoved(removed); maxFeeRateRemoved = std::max(maxFeeRateRemoved, removed); setEntries stage; CalculateDescendants(mapTx.project<0>(it), stage); nTxnRemoved += stage.size(); std::vector txn; if (pvNoSpendsRemaining) { txn.reserve(stage.size()); for (txiter iter : stage) { txn.push_back(iter->GetTx()); } } RemoveStaged(stage, false, MemPoolRemovalReason::SIZELIMIT); if (pvNoSpendsRemaining) { for (const CTransaction &tx : txn) { for (const CTxIn &txin : tx.vin) { if (exists(txin.prevout.GetTxId())) { continue; } - if (!mapNextTx.count(txin.prevout)) { - pvNoSpendsRemaining->push_back(txin.prevout); - } + pvNoSpendsRemaining->push_back(txin.prevout); } } } } if (maxFeeRateRemoved > CFeeRate(Amount::zero())) { LogPrint(BCLog::MEMPOOL, "Removed %u txn, rolling minimum fee bumped to %s\n", nTxnRemoved, maxFeeRateRemoved.ToString()); } } uint64_t CTxMemPool::CalculateDescendantMaximum(txiter entry) const { // find parent with highest descendant count std::vector candidates; setEntries counted; candidates.push_back(entry); uint64_t maximum = 0; while (candidates.size()) { txiter candidate = candidates.back(); candidates.pop_back(); if (!counted.insert(candidate).second) { continue; } const setEntries &parents = GetMemPoolParents(candidate); if (parents.size() == 0) { maximum = std::max(maximum, candidate->GetCountWithDescendants()); } else { for (txiter i : parents) { candidates.push_back(i); } } } return maximum; } void CTxMemPool::GetTransactionAncestry(const uint256 &txid, size_t &ancestors, size_t &descendants) const { LOCK(cs); auto it = mapTx.find(txid); ancestors = descendants = 0; if (it != mapTx.end()) { ancestors = it->GetCountWithAncestors(); descendants = CalculateDescendantMaximum(it); } } SaltedTxidHasher::SaltedTxidHasher() : k0(GetRand(std::numeric_limits::max())), k1(GetRand(std::numeric_limits::max())) {} /** Maximum bytes for transactions to store for processing during reorg */ static const size_t MAX_DISCONNECTED_TX_POOL_SIZE = 20 * DEFAULT_MAX_BLOCK_SIZE; void DisconnectedBlockTransactions::addForBlock( const std::vector &vtx) { for (const auto &tx : reverse_iterate(vtx)) { // If we already added it, just skip. auto it = queuedTx.find(tx->GetId()); if (it != queuedTx.end()) { continue; } // Insert the transaction into the pool. addTransaction(tx); // Fill in the set of parents. std::unordered_set parents; for (const CTxIn &in : tx->vin) { parents.insert(in.prevout.GetTxId()); } // In order to make sure we keep things in topological order, we check // if we already know of the parent of the current transaction. If so, // we remove them from the set and then add them back. while (parents.size() > 0) { std::unordered_set worklist( std::move(parents)); parents.clear(); for (const TxId &txid : worklist) { // If we do not have that txid in the set, nothing needs to be // done. auto pit = queuedTx.find(txid); if (pit == queuedTx.end()) { continue; } // We have parent in our set, we reinsert them at the right // position. const CTransactionRef ptx = *pit; queuedTx.erase(pit); queuedTx.insert(ptx); // And we make sure ancestors are covered. for (const CTxIn &in : ptx->vin) { parents.insert(in.prevout.GetTxId()); } } } } // Keep the size under control. while (DynamicMemoryUsage() > MAX_DISCONNECTED_TX_POOL_SIZE) { // Drop the earliest entry, and remove its children from the // mempool. auto it = queuedTx.get().begin(); g_mempool.removeRecursive(**it, MemPoolRemovalReason::REORG); removeEntry(it); } } void DisconnectedBlockTransactions::importMempool(CTxMemPool &pool) { // addForBlock's algorithm sorts a vector of transactions back into // topological order. We use it in a separate object to create a valid // ordering of all mempool transactions, which we then splice in front of // the current queuedTx. This results in a valid sequence of transactions to // be reprocessed in updateMempoolForReorg. // We create vtx in order of the entry_time index to facilitate for // addForBlocks (which iterates in reverse order), as vtx probably end in // the correct ordering for queuedTx. std::vector vtx; { LOCK(pool.cs); vtx.reserve(pool.mapTx.size()); for (const CTxMemPoolEntry &e : pool.mapTx.get()) { vtx.push_back(e.GetSharedTx()); } pool.clear(); } // Use addForBlocks to sort the transactions and then splice them in front // of queuedTx DisconnectedBlockTransactions orderedTxnPool; orderedTxnPool.addForBlock(vtx); cachedInnerUsage += orderedTxnPool.cachedInnerUsage; queuedTx.get().splice( queuedTx.get().begin(), orderedTxnPool.queuedTx.get()); // We limit memory usage because we can't know if more blocks will be // disconnected while (DynamicMemoryUsage() > MAX_DISCONNECTED_TX_POOL_SIZE) { // Drop the earliest entry which, by definition, has no children removeEntry(queuedTx.get().begin()); } } void DisconnectedBlockTransactions::updateMempoolForReorg(const Config &config, bool fAddToMempool) { AssertLockHeld(cs_main); std::vector txidsUpdate; // disconnectpool's insertion_order index sorts the entries from oldest to // newest, but the oldest entry will be the last tx from the latest mined // block that was disconnected. // Iterate disconnectpool in reverse, so that we add transactions back to // the mempool starting with the earliest transaction that had been // previously seen in a block. for (const CTransactionRef &tx : reverse_iterate(queuedTx.get())) { // ignore validation errors in resurrected transactions CValidationState stateDummy; if (!fAddToMempool || tx->IsCoinBase() || !AcceptToMemoryPool(config, g_mempool, stateDummy, tx, false, nullptr, true)) { // If the transaction doesn't make it in to the mempool, remove any // transactions that depend on it (which would now be orphans). g_mempool.removeRecursive(*tx, MemPoolRemovalReason::REORG); } else if (g_mempool.exists(tx->GetId())) { txidsUpdate.push_back(tx->GetId()); } } queuedTx.clear(); // AcceptToMemoryPool/addUnchecked all assume that new mempool entries have // no in-mempool children, which is generally not true when adding // previously-confirmed transactions back to the mempool. // UpdateTransactionsFromBlock finds descendants of any transactions in the // disconnectpool that were added back and cleans up the mempool state. g_mempool.UpdateTransactionsFromBlock(txidsUpdate); // We also need to remove any now-immature transactions g_mempool.removeForReorg(config, pcoinsTip.get(), chainActive.Tip()->nHeight + 1, STANDARD_LOCKTIME_VERIFY_FLAGS); // Re-limit mempool size, in case we added any transactions g_mempool.LimitSize( gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000, gArgs.GetArg("-mempoolexpiry", DEFAULT_MEMPOOL_EXPIRY) * 60 * 60); }