txmempool.cpp raw

   1  // Copyright (c) 2009-2010 Satoshi Nakamoto
   2  // Copyright (c) 2009-present The Bitcoin Core developers
   3  // Distributed under the MIT software license, see the accompanying
   4  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   5  
   6  #include <txmempool.h>
   7  
   8  #include <chain.h>
   9  #include <coins.h>
  10  #include <common/system.h>
  11  #include <consensus/consensus.h>
  12  #include <consensus/tx_verify.h>
  13  #include <consensus/validation.h>
  14  #include <policy/policy.h>
  15  #include <policy/settings.h>
  16  #include <random.h>
  17  #include <tinyformat.h>
  18  #include <util/check.h>
  19  #include <util/feefrac.h>
  20  #include <util/log.h>
  21  #include <util/moneystr.h>
  22  #include <util/overflow.h>
  23  #include <util/result.h>
  24  #include <util/time.h>
  25  #include <util/trace.h>
  26  #include <util/translation.h>
  27  #include <validationinterface.h>
  28  
  29  #include <algorithm>
  30  #include <cmath>
  31  #include <numeric>
  32  #include <optional>
  33  #include <ranges>
  34  #include <string_view>
  35  #include <utility>
  36  
  37  TRACEPOINT_SEMAPHORE(mempool, added);
  38  TRACEPOINT_SEMAPHORE(mempool, removed);
  39  
  40  bool TestLockPointValidity(CChain& active_chain, const LockPoints& lp)
  41  {
  42      AssertLockHeld(cs_main);
  43      // If there are relative lock times then the maxInputBlock will be set
  44      // If there are no relative lock times, the LockPoints don't depend on the chain
  45      if (lp.maxInputBlock) {
  46          // Check whether active_chain is an extension of the block at which the LockPoints
  47          // calculation was valid.  If not LockPoints are no longer valid
  48          if (!active_chain.Contains(*lp.maxInputBlock)) {
  49              return false;
  50          }
  51      }
  52  
  53      // LockPoints still valid
  54      return true;
  55  }
  56  
  57  std::vector<CTxMemPoolEntry::CTxMemPoolEntryRef> CTxMemPool::GetChildren(const CTxMemPoolEntry& entry) const
  58  {
  59      std::vector<CTxMemPoolEntry::CTxMemPoolEntryRef> ret;
  60      const auto& hash = entry.GetTx().GetHash();
  61      {
  62          LOCK(cs);
  63          auto iter = mapNextTx.lower_bound(COutPoint(hash, 0));
  64          for (; iter != mapNextTx.end() && iter->first->hash == hash; ++iter) {
  65              ret.emplace_back(*(iter->second));
  66          }
  67      }
  68      std::ranges::sort(ret, CompareIteratorByHash{});
  69      auto removed = std::ranges::unique(ret, [](auto& a, auto& b) noexcept { return &a.get() == &b.get(); });
  70      ret.erase(removed.begin(), removed.end());
  71      return ret;
  72  }
  73  
  74  std::vector<CTxMemPoolEntry::CTxMemPoolEntryRef> CTxMemPool::GetParents(const CTxMemPoolEntry& entry) const
  75  {
  76      LOCK(cs);
  77      std::vector<CTxMemPoolEntry::CTxMemPoolEntryRef> ret;
  78      std::set<Txid> inputs;
  79      for (const auto& txin : entry.GetTx().vin) {
  80          inputs.insert(txin.prevout.hash);
  81      }
  82      for (const auto& hash : inputs) {
  83          std::optional<txiter> piter = GetIter(hash);
  84          if (piter) {
  85              ret.emplace_back(**piter);
  86          }
  87      }
  88      return ret;
  89  }
  90  
  91  void CTxMemPool::UpdateTransactionsFromBlock(const std::vector<Txid>& vHashesToUpdate)
  92  {
  93      AssertLockHeld(cs);
  94  
  95      // Iterate in reverse, so that whenever we are looking at a transaction
  96      // we are sure that all in-mempool descendants have already been processed.
  97      for (const Txid& hash : vHashesToUpdate | std::views::reverse) {
  98          // calculate children from mapNextTx
  99          txiter it = mapTx.find(hash);
 100          if (it == mapTx.end()) {
 101              continue;
 102          }
 103          auto iter = mapNextTx.lower_bound(COutPoint(hash, 0));
 104          {
 105              for (; iter != mapNextTx.end() && iter->first->hash == hash; ++iter) {
 106                  txiter childIter = iter->second;
 107                  assert(childIter != mapTx.end());
 108                  // Add dependencies that are discovered between transactions in the
 109                  // block and transactions that were in the mempool to txgraph.
 110                  m_txgraph->AddDependency(/*parent=*/*it, /*child=*/*childIter);
 111              }
 112          }
 113      }
 114  
 115      auto txs_to_remove = m_txgraph->Trim(); // Enforce cluster size limits.
 116      for (auto txptr : txs_to_remove) {
 117          const CTxMemPoolEntry& entry = *(static_cast<const CTxMemPoolEntry*>(txptr));
 118          removeUnchecked(mapTx.iterator_to(entry), MemPoolRemovalReason::SIZELIMIT);
 119      }
 120  }
 121  
 122  bool CTxMemPool::HasDescendants(const Txid& txid) const
 123  {
 124      LOCK(cs);
 125      auto entry = GetEntry(txid);
 126      if (!entry) return false;
 127      return m_txgraph->GetDescendants(*entry, TxGraph::Level::MAIN).size() > 1;
 128  }
 129  
 130  CTxMemPool::setEntries CTxMemPool::CalculateMemPoolAncestors(const CTxMemPoolEntry &entry) const
 131  {
 132      auto ancestors = m_txgraph->GetAncestors(entry, TxGraph::Level::MAIN);
 133      setEntries ret;
 134      if (ancestors.size() > 0) {
 135          for (auto ancestor : ancestors) {
 136              if (ancestor != &entry) {
 137                  ret.insert(mapTx.iterator_to(static_cast<const CTxMemPoolEntry&>(*ancestor)));
 138              }
 139          }
 140          return ret;
 141      }
 142  
 143      // If we didn't get anything back, the transaction is not in the graph.
 144      // Find each parent and call GetAncestors on each.
 145      setEntries staged_parents;
 146      const CTransaction &tx = entry.GetTx();
 147  
 148      // Get parents of this transaction that are in the mempool
 149      for (unsigned int i = 0; i < tx.vin.size(); i++) {
 150          std::optional<txiter> piter = GetIter(tx.vin[i].prevout.hash);
 151          if (piter) {
 152              staged_parents.insert(*piter);
 153          }
 154      }
 155  
 156      for (const auto& parent : staged_parents) {
 157          auto parent_ancestors = m_txgraph->GetAncestors(*parent, TxGraph::Level::MAIN);
 158          for (auto ancestor : parent_ancestors) {
 159              ret.insert(mapTx.iterator_to(static_cast<const CTxMemPoolEntry&>(*ancestor)));
 160          }
 161      }
 162  
 163      return ret;
 164  }
 165  
 166  static CTxMemPool::Options&& Flatten(CTxMemPool::Options&& opts, bilingual_str& error)
 167  {
 168      opts.check_ratio = std::clamp<int>(opts.check_ratio, 0, 1'000'000);
 169      int64_t cluster_limit_bytes = opts.limits.cluster_size_vbytes * 40;
 170      if (opts.max_size_bytes < 0 || (opts.max_size_bytes > 0 && opts.max_size_bytes < cluster_limit_bytes)) {
 171          error = strprintf(_("-maxmempool must be at least %d MB"), std::ceil(cluster_limit_bytes / 1'000'000.0));
 172      }
 173      return std::move(opts);
 174  }
 175  
 176  CTxMemPool::CTxMemPool(Options opts, bilingual_str& error)
 177      : m_opts{Flatten(std::move(opts), error)}
 178  {
 179      m_txgraph = MakeTxGraph(
 180          /*max_cluster_count=*/m_opts.limits.cluster_count,
 181          /*max_cluster_size=*/m_opts.limits.cluster_size_vbytes * WITNESS_SCALE_FACTOR,
 182          /*acceptable_cost=*/ACCEPTABLE_COST,
 183          /*fallback_order=*/[&](const TxGraph::Ref& a, const TxGraph::Ref& b) noexcept {
 184              const Txid& txid_a = static_cast<const CTxMemPoolEntry&>(a).GetTx().GetHash();
 185              const Txid& txid_b = static_cast<const CTxMemPoolEntry&>(b).GetTx().GetHash();
 186              return txid_a <=> txid_b;
 187          });
 188  }
 189  
 190  bool CTxMemPool::isSpent(const COutPoint& outpoint) const
 191  {
 192      LOCK(cs);
 193      return mapNextTx.count(outpoint);
 194  }
 195  
 196  unsigned int CTxMemPool::GetTransactionsUpdated() const
 197  {
 198      return nTransactionsUpdated;
 199  }
 200  
 201  void CTxMemPool::AddTransactionsUpdated(unsigned int n)
 202  {
 203      nTransactionsUpdated += n;
 204  }
 205  
 206  void CTxMemPool::Apply(ChangeSet* changeset)
 207  {
 208      AssertLockHeld(cs);
 209      m_txgraph->CommitStaging();
 210  
 211      RemoveStaged(changeset->m_to_remove, MemPoolRemovalReason::REPLACED);
 212  
 213      for (size_t i=0; i<changeset->m_entry_vec.size(); ++i) {
 214          auto tx_entry = changeset->m_entry_vec[i];
 215          // First splice this entry into mapTx.
 216          auto node_handle = changeset->m_to_add.extract(tx_entry);
 217          auto result = mapTx.insert(std::move(node_handle));
 218  
 219          Assume(result.inserted);
 220          txiter it = result.position;
 221  
 222          addNewTransaction(it);
 223      }
 224      if (!m_txgraph->DoWork(/*max_cost=*/POST_CHANGE_COST)) {
 225          LogDebug(BCLog::MEMPOOL, "Mempool in non-optimal ordering after addition(s).");
 226      }
 227  }
 228  
 229  void CTxMemPool::addNewTransaction(CTxMemPool::txiter newit)
 230  {
 231      const CTxMemPoolEntry& entry = *newit;
 232  
 233      // Update cachedInnerUsage to include contained transaction's usage.
 234      // (When we update the entry for in-mempool parents, memory usage will be
 235      // further updated.)
 236      cachedInnerUsage += entry.DynamicMemoryUsage();
 237  
 238      const CTransaction& tx = newit->GetTx();
 239      for (unsigned int i = 0; i < tx.vin.size(); i++) {
 240          mapNextTx.insert(std::make_pair(&tx.vin[i].prevout, newit));
 241      }
 242      // Don't bother worrying about child transactions of this one.
 243      // Normal case of a new transaction arriving is that there can't be any
 244      // children, because such children would be orphans.
 245      // An exception to that is if a transaction enters that used to be in a block.
 246      // In that case, our disconnect block logic will call UpdateTransactionsFromBlock
 247      // to clean up the mess we're leaving here.
 248  
 249      nTransactionsUpdated++;
 250      totalTxSize += entry.GetTxSize();
 251      m_total_fee += entry.GetFee();
 252  
 253      txns_randomized.emplace_back(tx.GetWitnessHash(), newit);
 254      newit->idx_randomized = txns_randomized.size() - 1;
 255  
 256      TRACEPOINT(mempool, added,
 257          entry.GetTx().GetHash().data(),
 258          entry.GetTxSize(),
 259          entry.GetFee()
 260      );
 261  }
 262  
 263  void CTxMemPool::removeUnchecked(txiter it, MemPoolRemovalReason reason)
 264  {
 265      // We increment mempool sequence value no matter removal reason
 266      // even if not directly reported below.
 267      uint64_t mempool_sequence = GetAndIncrementSequence();
 268  
 269      if (reason != MemPoolRemovalReason::BLOCK && m_opts.signals) {
 270          // Notify clients that a transaction has been removed from the mempool
 271          // for any reason except being included in a block. Clients interested
 272          // in transactions included in blocks can subscribe to the BlockConnected
 273          // notification.
 274          m_opts.signals->TransactionRemovedFromMempool(it->GetSharedTx(), reason, mempool_sequence);
 275      }
 276      TRACEPOINT(mempool, removed,
 277          it->GetTx().GetHash().data(),
 278          RemovalReasonToString(reason).c_str(),
 279          it->GetTxSize(),
 280          it->GetFee(),
 281          std::chrono::duration_cast<std::chrono::duration<std::uint64_t>>(it->GetTime()).count()
 282      );
 283  
 284      for (const CTxIn& txin : it->GetTx().vin)
 285          mapNextTx.erase(txin.prevout);
 286  
 287      RemoveUnbroadcastTx(it->GetTx().GetHash(), true /* add logging because unchecked */);
 288  
 289      if (txns_randomized.size() > 1) {
 290          // Remove entry from txns_randomized by replacing it with the back and deleting the back.
 291          txns_randomized[it->idx_randomized] = std::move(txns_randomized.back());
 292          txns_randomized[it->idx_randomized].second->idx_randomized = it->idx_randomized;
 293          txns_randomized.pop_back();
 294          if (txns_randomized.size() * 2 < txns_randomized.capacity()) {
 295              txns_randomized.shrink_to_fit();
 296          }
 297      } else {
 298          txns_randomized.clear();
 299      }
 300  
 301      totalTxSize -= it->GetTxSize();
 302      m_total_fee -= it->GetFee();
 303      cachedInnerUsage -= it->DynamicMemoryUsage();
 304      mapTx.erase(it);
 305      nTransactionsUpdated++;
 306  }
 307  
 308  // Calculates descendants of given entry and adds to setDescendants.
 309  void CTxMemPool::CalculateDescendants(txiter entryit, setEntries& setDescendants) const
 310  {
 311      (void)CalculateDescendants(*entryit, setDescendants);
 312      return;
 313  }
 314  
 315  CTxMemPool::txiter CTxMemPool::CalculateDescendants(const CTxMemPoolEntry& entry, setEntries& setDescendants) const
 316  {
 317      for (auto tx : m_txgraph->GetDescendants(entry, TxGraph::Level::MAIN)) {
 318          setDescendants.insert(mapTx.iterator_to(static_cast<const CTxMemPoolEntry&>(*tx)));
 319      }
 320      return mapTx.iterator_to(entry);
 321  }
 322  
 323  void CTxMemPool::removeRecursive(CTxMemPool::txiter to_remove, MemPoolRemovalReason reason)
 324  {
 325      AssertLockHeld(cs);
 326      Assume(!m_have_changeset);
 327      auto descendants = m_txgraph->GetDescendants(*to_remove, TxGraph::Level::MAIN);
 328      for (auto tx: descendants) {
 329          removeUnchecked(mapTx.iterator_to(static_cast<const CTxMemPoolEntry&>(*tx)), reason);
 330      }
 331  }
 332  
 333  void CTxMemPool::removeRecursive(const CTransaction &origTx, MemPoolRemovalReason reason)
 334  {
 335      // Remove transaction from memory pool
 336      AssertLockHeld(cs);
 337      Assume(!m_have_changeset);
 338      txiter origit = mapTx.find(origTx.GetHash());
 339      if (origit != mapTx.end()) {
 340          removeRecursive(origit, reason);
 341      } else {
 342          // When recursively removing but origTx isn't in the mempool
 343          // be sure to remove any descendants that are in the pool. This can
 344          // happen during chain re-orgs if origTx isn't re-accepted into
 345          // the mempool for any reason.
 346          auto iter = mapNextTx.lower_bound(COutPoint(origTx.GetHash(), 0));
 347          std::vector<const TxGraph::Ref*> to_remove;
 348          while (iter != mapNextTx.end() && iter->first->hash == origTx.GetHash()) {
 349              to_remove.emplace_back(&*(iter->second));
 350              ++iter;
 351          }
 352          auto all_removes = m_txgraph->GetDescendantsUnion(to_remove, TxGraph::Level::MAIN);
 353          for (auto ref : all_removes) {
 354              auto tx = mapTx.iterator_to(static_cast<const CTxMemPoolEntry&>(*ref));
 355              removeUnchecked(tx, reason);
 356          }
 357      }
 358  }
 359  
 360  void CTxMemPool::removeForReorg(CChain& chain, std::function<bool(txiter)> check_final_and_mature)
 361  {
 362      // Remove transactions spending a coinbase which are now immature and no-longer-final transactions
 363      AssertLockHeld(cs);
 364      AssertLockHeld(::cs_main);
 365      Assume(!m_have_changeset);
 366  
 367      std::vector<const TxGraph::Ref*> to_remove;
 368      for (txiter it = mapTx.begin(); it != mapTx.end(); it++) {
 369          if (check_final_and_mature(it)) {
 370              to_remove.emplace_back(&*it);
 371          }
 372      }
 373  
 374      auto all_to_remove = m_txgraph->GetDescendantsUnion(to_remove, TxGraph::Level::MAIN);
 375  
 376      for (auto ref : all_to_remove) {
 377          auto it = mapTx.iterator_to(static_cast<const CTxMemPoolEntry&>(*ref));
 378          removeUnchecked(it, MemPoolRemovalReason::REORG);
 379      }
 380      for (indexed_transaction_set::const_iterator it = mapTx.begin(); it != mapTx.end(); it++) {
 381          assert(TestLockPointValidity(chain, it->GetLockPoints()));
 382      }
 383      if (!m_txgraph->DoWork(/*max_cost=*/POST_CHANGE_COST)) {
 384          LogDebug(BCLog::MEMPOOL, "Mempool in non-optimal ordering after reorg.");
 385      }
 386  }
 387  
 388  void CTxMemPool::removeConflicts(const CTransaction &tx)
 389  {
 390      // Remove transactions which depend on inputs of tx, recursively
 391      AssertLockHeld(cs);
 392      for (const CTxIn &txin : tx.vin) {
 393          auto it = mapNextTx.find(txin.prevout);
 394          if (it != mapNextTx.end()) {
 395              const CTransaction &txConflict = it->second->GetTx();
 396              if (Assume(txConflict.GetHash() != tx.GetHash()))
 397              {
 398                  ClearPrioritisation(txConflict.GetHash());
 399                  removeRecursive(it->second, MemPoolRemovalReason::CONFLICT);
 400              }
 401          }
 402      }
 403  }
 404  
 405  void CTxMemPool::removeForBlock(const std::vector<CTransactionRef>& vtx, unsigned int nBlockHeight)
 406  {
 407      // Remove confirmed txs and conflicts when a new block is connected, updating the fee logic
 408      AssertLockHeld(cs);
 409      Assume(!m_have_changeset);
 410      std::vector<RemovedMempoolTransactionInfo> txs_removed_for_block;
 411      if (mapTx.size() || mapNextTx.size() || mapDeltas.size()) {
 412          txs_removed_for_block.reserve(vtx.size());
 413          for (const auto& tx : vtx) {
 414              txiter it = mapTx.find(tx->GetHash());
 415              if (it != mapTx.end()) {
 416                  txs_removed_for_block.emplace_back(*it);
 417                  removeUnchecked(it, MemPoolRemovalReason::BLOCK);
 418              }
 419              removeConflicts(*tx);
 420              ClearPrioritisation(tx->GetHash());
 421          }
 422      }
 423      if (m_opts.signals) {
 424          m_opts.signals->MempoolTransactionsRemovedForBlock(txs_removed_for_block, nBlockHeight);
 425      }
 426      lastRollingFeeUpdate = GetTime();
 427      blockSinceLastRollingFeeBump = true;
 428      if (!m_txgraph->DoWork(/*max_cost=*/POST_CHANGE_COST)) {
 429          LogDebug(BCLog::MEMPOOL, "Mempool in non-optimal ordering after block.");
 430      }
 431  }
 432  
 433  void CTxMemPool::check(const CCoinsViewCache& active_coins_tip, int64_t spendheight) const
 434  {
 435      if (m_opts.check_ratio == 0) return;
 436  
 437      if (FastRandomContext().randrange(m_opts.check_ratio) >= 1) return;
 438  
 439      AssertLockHeld(::cs_main);
 440      LOCK(cs);
 441      LogDebug(BCLog::MEMPOOL, "Checking mempool with %u transactions and %u inputs\n", (unsigned int)mapTx.size(), (unsigned int)mapNextTx.size());
 442  
 443      uint64_t checkTotal = 0;
 444      CAmount check_total_fee{0};
 445      CAmount check_total_modified_fee{0};
 446      int64_t check_total_adjusted_weight{0};
 447      uint64_t innerUsage = 0;
 448  
 449      assert(!m_txgraph->IsOversized(TxGraph::Level::MAIN));
 450      m_txgraph->SanityCheck();
 451  
 452      CCoinsViewCache mempoolDuplicate(const_cast<CCoinsViewCache*>(&active_coins_tip));
 453  
 454      const auto score_with_topo{GetSortedScoreWithTopology()};
 455  
 456      // Number of chunks is bounded by number of transactions.
 457      const auto diagram{GetFeerateDiagram()};
 458      assert(diagram.size() <= score_with_topo.size() + 1);
 459      assert(diagram.size() >= 1);
 460  
 461      std::optional<Wtxid> last_wtxid = std::nullopt;
 462      auto diagram_iter = diagram.cbegin();
 463  
 464      for (const auto& it : score_with_topo) {
 465          // GetSortedScoreWithTopology() contains the same chunks as the feerate
 466          // diagram. We do not know where the chunk boundaries are, but we can
 467          // check that there are points at which they match the cumulative fee
 468          // and weight.
 469          // The feerate diagram should never get behind the current transaction
 470          // size totals.
 471          assert(diagram_iter->size >= check_total_adjusted_weight);
 472          if (diagram_iter->fee == check_total_modified_fee &&
 473                  diagram_iter->size == check_total_adjusted_weight) {
 474              ++diagram_iter;
 475          }
 476          checkTotal += it->GetTxSize();
 477          check_total_adjusted_weight += it->GetAdjustedWeight();
 478          check_total_fee += it->GetFee();
 479          check_total_modified_fee += it->GetModifiedFee();
 480          innerUsage += it->DynamicMemoryUsage();
 481          const CTransaction& tx = it->GetTx();
 482  
 483          // CompareMiningScoreWithTopology should agree with GetSortedScoreWithTopology()
 484          if (last_wtxid) {
 485              assert(CompareMiningScoreWithTopology(*last_wtxid, tx.GetWitnessHash()));
 486          }
 487          last_wtxid = tx.GetWitnessHash();
 488  
 489          std::set<CTxMemPoolEntry::CTxMemPoolEntryRef, CompareIteratorByHash> setParentCheck;
 490          std::set<CTxMemPoolEntry::CTxMemPoolEntryRef, CompareIteratorByHash> setParentsStored;
 491          for (const CTxIn &txin : tx.vin) {
 492              // Check that every mempool transaction's inputs refer to available coins, or other mempool tx's.
 493              indexed_transaction_set::const_iterator it2 = mapTx.find(txin.prevout.hash);
 494              if (it2 != mapTx.end()) {
 495                  const CTransaction& tx2 = it2->GetTx();
 496                  assert(tx2.vout.size() > txin.prevout.n && !tx2.vout[txin.prevout.n].IsNull());
 497                  setParentCheck.insert(*it2);
 498              }
 499              // We are iterating through the mempool entries sorted
 500              // topologically and by mining score. All parents must have been
 501              // checked before their children and their coins added to the
 502              // mempoolDuplicate coins cache.
 503              assert(mempoolDuplicate.HaveCoin(txin.prevout));
 504              // Check whether its inputs are marked in mapNextTx.
 505              auto it3 = mapNextTx.find(txin.prevout);
 506              assert(it3 != mapNextTx.end());
 507              assert(it3->first == &txin.prevout);
 508              assert(&it3->second->GetTx() == &tx);
 509          }
 510          auto comp = [](const CTxMemPoolEntry& a, const CTxMemPoolEntry& b) -> bool {
 511              return a.GetTx().GetHash() == b.GetTx().GetHash();
 512          };
 513          for (auto &txentry : GetParents(*it)) {
 514              setParentsStored.insert(dynamic_cast<const CTxMemPoolEntry&>(txentry.get()));
 515          }
 516          assert(setParentCheck.size() == setParentsStored.size());
 517          assert(std::equal(setParentCheck.begin(), setParentCheck.end(), setParentsStored.begin(), comp));
 518  
 519          // Check children against mapNextTx
 520          std::set<CTxMemPoolEntry::CTxMemPoolEntryRef, CompareIteratorByHash> setChildrenCheck;
 521          std::set<CTxMemPoolEntry::CTxMemPoolEntryRef, CompareIteratorByHash> setChildrenStored;
 522          auto iter = mapNextTx.lower_bound(COutPoint(it->GetTx().GetHash(), 0));
 523          for (; iter != mapNextTx.end() && iter->first->hash == it->GetTx().GetHash(); ++iter) {
 524              txiter childit = iter->second;
 525              assert(childit != mapTx.end()); // mapNextTx points to in-mempool transactions
 526              setChildrenCheck.insert(*childit);
 527          }
 528          for (auto &txentry : GetChildren(*it)) {
 529              setChildrenStored.insert(dynamic_cast<const CTxMemPoolEntry&>(txentry.get()));
 530          }
 531          assert(setChildrenCheck.size() == setChildrenStored.size());
 532          assert(std::equal(setChildrenCheck.begin(), setChildrenCheck.end(), setChildrenStored.begin(), comp));
 533  
 534          TxValidationState dummy_state; // Not used. CheckTxInputs() should always pass
 535          CAmount txfee = 0;
 536          assert(!tx.IsCoinBase());
 537          assert(Consensus::CheckTxInputs(tx, dummy_state, mempoolDuplicate, spendheight, txfee));
 538          for (const auto& input: tx.vin) mempoolDuplicate.SpendCoin(input.prevout);
 539          AddCoins(mempoolDuplicate, tx, std::numeric_limits<int>::max());
 540      }
 541      for (auto it = mapNextTx.cbegin(); it != mapNextTx.cend(); it++) {
 542          indexed_transaction_set::const_iterator it2 = it->second;
 543          assert(it2 != mapTx.end());
 544      }
 545  
 546      ++diagram_iter;
 547      assert(diagram_iter == diagram.cend());
 548  
 549      assert(totalTxSize == checkTotal);
 550      assert(m_total_fee == check_total_fee);
 551      assert(diagram.back().fee == check_total_modified_fee);
 552      assert(diagram.back().size == check_total_adjusted_weight);
 553      assert(innerUsage == cachedInnerUsage);
 554  }
 555  
 556  bool CTxMemPool::CompareMiningScoreWithTopology(const Wtxid& hasha, const Wtxid& hashb) const
 557  {
 558      /* Return `true` if hasha should be considered sooner than hashb, namely when:
 559       *     a is not in the mempool but b is, or
 560       *     both are in the mempool but a is sorted before b in the total mempool ordering
 561       *     (which takes dependencies and (chunk) feerates into account).
 562       */
 563      LOCK(cs);
 564      auto j{GetIter(hashb)};
 565      if (!j.has_value()) return false;
 566      auto i{GetIter(hasha)};
 567      if (!i.has_value()) return true;
 568  
 569      return m_txgraph->CompareMainOrder(*i.value(), *j.value()) < 0;
 570  }
 571  
 572  std::vector<CTxMemPool::indexed_transaction_set::const_iterator> CTxMemPool::GetSortedScoreWithTopology() const
 573  {
 574      std::vector<indexed_transaction_set::const_iterator> iters;
 575      AssertLockHeld(cs);
 576  
 577      iters.reserve(mapTx.size());
 578  
 579      for (indexed_transaction_set::iterator mi = mapTx.begin(); mi != mapTx.end(); ++mi) {
 580          iters.push_back(mi);
 581      }
 582      std::sort(iters.begin(), iters.end(), [this](const auto& a, const auto& b) EXCLUSIVE_LOCKS_REQUIRED(cs) noexcept {
 583          return m_txgraph->CompareMainOrder(*a, *b) < 0;
 584      });
 585      return iters;
 586  }
 587  
 588  std::vector<CTxMemPoolEntryRef> CTxMemPool::entryAll() const
 589  {
 590      AssertLockHeld(cs);
 591  
 592      std::vector<CTxMemPoolEntryRef> ret;
 593      ret.reserve(mapTx.size());
 594      for (const auto& it : GetSortedScoreWithTopology()) {
 595          ret.emplace_back(*it);
 596      }
 597      return ret;
 598  }
 599  
 600  std::vector<TxMempoolInfo> CTxMemPool::infoAll() const
 601  {
 602      LOCK(cs);
 603      auto iters = GetSortedScoreWithTopology();
 604  
 605      std::vector<TxMempoolInfo> ret;
 606      ret.reserve(mapTx.size());
 607      for (auto it : iters) {
 608          ret.push_back(GetInfo(it));
 609      }
 610  
 611      return ret;
 612  }
 613  
 614  const CTxMemPoolEntry* CTxMemPool::GetEntry(const Txid& txid) const
 615  {
 616      AssertLockHeld(cs);
 617      const auto i = mapTx.find(txid);
 618      return i == mapTx.end() ? nullptr : &(*i);
 619  }
 620  
 621  CTransactionRef CTxMemPool::get(const Txid& hash) const
 622  {
 623      LOCK(cs);
 624      indexed_transaction_set::const_iterator i = mapTx.find(hash);
 625      if (i == mapTx.end())
 626          return nullptr;
 627      return i->GetSharedTx();
 628  }
 629  
 630  CTransactionRef CTxMemPool::get(const Wtxid& hash) const
 631  {
 632      LOCK(cs);
 633      const auto& wtxid_map{mapTx.get<index_by_wtxid>()};
 634      const auto it{wtxid_map.find(hash)};
 635      if (it == wtxid_map.end()) return nullptr;
 636      return it->GetSharedTx();
 637  }
 638  
 639  void CTxMemPool::PrioritiseTransaction(const Txid& hash, const CAmount& nFeeDelta)
 640  {
 641      {
 642          LOCK(cs);
 643          CAmount &delta = mapDeltas[hash];
 644          delta = SaturatingAdd(delta, nFeeDelta);
 645          txiter it = mapTx.find(hash);
 646          if (it != mapTx.end()) {
 647              // PrioritiseTransaction calls stack on previous ones. Set the new
 648              // transaction fee to be current modified fee + feedelta.
 649              it->UpdateModifiedFee(nFeeDelta);
 650              m_txgraph->SetTransactionFee(*it, it->GetModifiedFee());
 651              ++nTransactionsUpdated;
 652          }
 653          if (delta == 0) {
 654              mapDeltas.erase(hash);
 655              LogInfo("PrioritiseTransaction: %s (%sin mempool) delta cleared\n", hash.ToString(), it == mapTx.end() ? "not " : "");
 656          } else {
 657              LogInfo("PrioritiseTransaction: %s (%sin mempool) fee += %s, new delta=%s\n",
 658                        hash.ToString(),
 659                        it == mapTx.end() ? "not " : "",
 660                        FormatMoney(nFeeDelta),
 661                        FormatMoney(delta));
 662          }
 663      }
 664  }
 665  
 666  void CTxMemPool::ApplyDelta(const Txid& hash, CAmount &nFeeDelta) const
 667  {
 668      AssertLockHeld(cs);
 669      std::map<Txid, CAmount>::const_iterator pos = mapDeltas.find(hash);
 670      if (pos == mapDeltas.end())
 671          return;
 672      const CAmount &delta = pos->second;
 673      nFeeDelta += delta;
 674  }
 675  
 676  void CTxMemPool::ClearPrioritisation(const Txid& hash)
 677  {
 678      AssertLockHeld(cs);
 679      mapDeltas.erase(hash);
 680  }
 681  
 682  std::vector<CTxMemPool::delta_info> CTxMemPool::GetPrioritisedTransactions() const
 683  {
 684      AssertLockNotHeld(cs);
 685      LOCK(cs);
 686      std::vector<delta_info> result;
 687      result.reserve(mapDeltas.size());
 688      for (const auto& [txid, delta] : mapDeltas) {
 689          const auto iter{mapTx.find(txid)};
 690          const bool in_mempool{iter != mapTx.end()};
 691          std::optional<CAmount> modified_fee;
 692          if (in_mempool) modified_fee = iter->GetModifiedFee();
 693          result.emplace_back(delta_info{in_mempool, delta, modified_fee, txid});
 694      }
 695      return result;
 696  }
 697  
 698  const CTransaction* CTxMemPool::GetConflictTx(const COutPoint& prevout) const
 699  {
 700      const auto it = mapNextTx.find(prevout);
 701      return it == mapNextTx.end() ? nullptr : &(it->second->GetTx());
 702  }
 703  
 704  std::optional<CTxMemPool::txiter> CTxMemPool::GetIter(const Txid& txid) const
 705  {
 706      AssertLockHeld(cs);
 707      auto it = mapTx.find(txid);
 708      return it != mapTx.end() ? std::make_optional(it) : std::nullopt;
 709  }
 710  
 711  std::optional<CTxMemPool::txiter> CTxMemPool::GetIter(const Wtxid& wtxid) const
 712  {
 713      AssertLockHeld(cs);
 714      auto it{mapTx.project<0>(mapTx.get<index_by_wtxid>().find(wtxid))};
 715      return it != mapTx.end() ? std::make_optional(it) : std::nullopt;
 716  }
 717  
 718  CTxMemPool::setEntries CTxMemPool::GetIterSet(const std::set<Txid>& hashes) const
 719  {
 720      CTxMemPool::setEntries ret;
 721      for (const auto& h : hashes) {
 722          const auto mi = GetIter(h);
 723          if (mi) ret.insert(*mi);
 724      }
 725      return ret;
 726  }
 727  
 728  std::vector<CTxMemPool::txiter> CTxMemPool::GetIterVec(const std::vector<Txid>& txids) const
 729  {
 730      AssertLockHeld(cs);
 731      std::vector<txiter> ret;
 732      ret.reserve(txids.size());
 733      for (const auto& txid : txids) {
 734          const auto it{GetIter(txid)};
 735          if (!it) return {};
 736          ret.push_back(*it);
 737      }
 738      return ret;
 739  }
 740  
 741  bool CTxMemPool::HasNoInputsOf(const CTransaction &tx) const
 742  {
 743      for (unsigned int i = 0; i < tx.vin.size(); i++)
 744          if (exists(tx.vin[i].prevout.hash))
 745              return false;
 746      return true;
 747  }
 748  
 749  CCoinsViewMemPool::CCoinsViewMemPool(CCoinsView* baseIn, const CTxMemPool& mempoolIn) : CCoinsViewBacked(baseIn), mempool(mempoolIn) { }
 750  
 751  std::optional<Coin> CCoinsViewMemPool::GetCoin(const COutPoint& outpoint) const
 752  {
 753      // Check to see if the inputs are made available by another tx in the package.
 754      // These Coins would not be available in the underlying CoinsView.
 755      if (auto it = m_temp_added.find(outpoint); it != m_temp_added.end()) {
 756          return it->second;
 757      }
 758  
 759      // If an entry in the mempool exists, always return that one, as it's guaranteed to never
 760      // conflict with the underlying cache, and it cannot have pruned entries (as it contains full)
 761      // transactions. First checking the underlying cache risks returning a pruned entry instead.
 762      CTransactionRef ptx = mempool.get(outpoint.hash);
 763      if (ptx) {
 764          if (outpoint.n < ptx->vout.size()) {
 765              Coin coin(ptx->vout[outpoint.n], MEMPOOL_HEIGHT, false);
 766              m_non_base_coins.emplace(outpoint);
 767              return coin;
 768          }
 769          return std::nullopt;
 770      }
 771      return base->GetCoin(outpoint);
 772  }
 773  
 774  void CCoinsViewMemPool::PackageAddTransaction(const CTransactionRef& tx)
 775  {
 776      for (unsigned int n = 0; n < tx->vout.size(); ++n) {
 777          m_temp_added.emplace(COutPoint(tx->GetHash(), n), Coin(tx->vout[n], MEMPOOL_HEIGHT, false));
 778          m_non_base_coins.emplace(tx->GetHash(), n);
 779      }
 780  }
 781  void CCoinsViewMemPool::Reset()
 782  {
 783      m_temp_added.clear();
 784      m_non_base_coins.clear();
 785  }
 786  
 787  size_t CTxMemPool::DynamicMemoryUsage() const {
 788      LOCK(cs);
 789      // Estimate the overhead of mapTx to be 9 pointers (3 pointers per index) + an allocation, as no exact formula for boost::multi_index_contained is implemented.
 790      return memusage::MallocUsage(sizeof(CTxMemPoolEntry) + 9 * sizeof(void*)) * mapTx.size() + memusage::DynamicUsage(mapNextTx) + memusage::DynamicUsage(mapDeltas) + memusage::DynamicUsage(txns_randomized) + m_txgraph->GetMainMemoryUsage() + cachedInnerUsage;
 791  }
 792  
 793  void CTxMemPool::RemoveUnbroadcastTx(const Txid& txid, const bool unchecked) {
 794      LOCK(cs);
 795  
 796      if (m_unbroadcast_txids.erase(txid))
 797      {
 798          LogDebug(BCLog::MEMPOOL, "Removed %s from set of unbroadcast txns%s", txid.GetHex(), (unchecked ? " before confirmation that txn was sent out" : ""));
 799      }
 800  }
 801  
 802  void CTxMemPool::RemoveStaged(setEntries &stage, MemPoolRemovalReason reason) {
 803      AssertLockHeld(cs);
 804      for (txiter it : stage) {
 805          removeUnchecked(it, reason);
 806      }
 807  }
 808  
 809  bool CTxMemPool::CheckPolicyLimits(const CTransactionRef& tx)
 810  {
 811      LOCK(cs);
 812      // Use ChangeSet interface to check whether the cluster count
 813      // limits would be violated. Note that the changeset will be destroyed
 814      // when it goes out of scope.
 815      auto changeset = GetChangeSet();
 816      (void) changeset->StageAddition(tx, /*fee=*/0, /*time=*/0, /*entry_height=*/0, /*entry_sequence=*/0, /*spends_coinbase=*/false, /*sigops_cost=*/0, LockPoints{});
 817      return changeset->CheckMemPoolPolicyLimits();
 818  }
 819  
 820  int CTxMemPool::Expire(std::chrono::seconds time)
 821  {
 822      AssertLockHeld(cs);
 823      Assume(!m_have_changeset);
 824      indexed_transaction_set::index<entry_time>::type::iterator it = mapTx.get<entry_time>().begin();
 825      setEntries toremove;
 826      while (it != mapTx.get<entry_time>().end() && it->GetTime() < time) {
 827          toremove.insert(mapTx.project<0>(it));
 828          it++;
 829      }
 830      setEntries stage;
 831      for (txiter removeit : toremove) {
 832          CalculateDescendants(removeit, stage);
 833      }
 834      RemoveStaged(stage, MemPoolRemovalReason::EXPIRY);
 835      return stage.size();
 836  }
 837  
 838  CFeeRate CTxMemPool::GetMinFee(size_t sizelimit) const {
 839      LOCK(cs);
 840      if (!blockSinceLastRollingFeeBump || rollingMinimumFeeRate == 0)
 841          return CFeeRate(llround(rollingMinimumFeeRate));
 842  
 843      int64_t time = GetTime();
 844      if (time > lastRollingFeeUpdate + 10) {
 845          double halflife = ROLLING_FEE_HALFLIFE;
 846          if (DynamicMemoryUsage() < sizelimit / 4)
 847              halflife /= 4;
 848          else if (DynamicMemoryUsage() < sizelimit / 2)
 849              halflife /= 2;
 850  
 851          rollingMinimumFeeRate = rollingMinimumFeeRate / pow(2.0, (time - lastRollingFeeUpdate) / halflife);
 852          lastRollingFeeUpdate = time;
 853  
 854          if (rollingMinimumFeeRate < (double)m_opts.incremental_relay_feerate.GetFeePerK() / 2) {
 855              rollingMinimumFeeRate = 0;
 856              return CFeeRate(0);
 857          }
 858      }
 859      return std::max(CFeeRate(llround(rollingMinimumFeeRate)), m_opts.incremental_relay_feerate);
 860  }
 861  
 862  void CTxMemPool::trackPackageRemoved(const CFeeRate& rate) {
 863      AssertLockHeld(cs);
 864      if (rate.GetFeePerK() > rollingMinimumFeeRate) {
 865          rollingMinimumFeeRate = rate.GetFeePerK();
 866          blockSinceLastRollingFeeBump = false;
 867      }
 868  }
 869  
 870  void CTxMemPool::TrimToSize(size_t sizelimit, std::vector<COutPoint>* pvNoSpendsRemaining) {
 871      AssertLockHeld(cs);
 872      Assume(!m_have_changeset);
 873  
 874      unsigned nTxnRemoved = 0;
 875      CFeeRate maxFeeRateRemoved(0);
 876  
 877      while (!mapTx.empty() && DynamicMemoryUsage() > sizelimit) {
 878          const auto &[worst_chunk, feeperweight] = m_txgraph->GetWorstMainChunk();
 879          FeePerVSize feerate = ToFeePerVSize(feeperweight);
 880          CFeeRate removed{feerate.fee, feerate.size};
 881  
 882          // We set the new mempool min fee to the feerate of the removed set, plus the
 883          // "minimum reasonable fee rate" (ie some value under which we consider txn
 884          // to have 0 fee). This way, we don't allow txn to enter mempool with feerate
 885          // equal to txn which were removed with no block in between.
 886          removed += m_opts.incremental_relay_feerate;
 887          trackPackageRemoved(removed);
 888          maxFeeRateRemoved = std::max(maxFeeRateRemoved, removed);
 889  
 890          nTxnRemoved += worst_chunk.size();
 891  
 892          std::vector<CTransaction> txn;
 893          if (pvNoSpendsRemaining) {
 894              txn.reserve(worst_chunk.size());
 895              for (auto ref : worst_chunk) {
 896                  txn.emplace_back(static_cast<const CTxMemPoolEntry&>(*ref).GetTx());
 897              }
 898          }
 899  
 900          setEntries stage;
 901          for (auto ref : worst_chunk) {
 902              stage.insert(mapTx.iterator_to(static_cast<const CTxMemPoolEntry&>(*ref)));
 903          }
 904          for (auto e : stage) {
 905              removeUnchecked(e, MemPoolRemovalReason::SIZELIMIT);
 906          }
 907          if (pvNoSpendsRemaining) {
 908              for (const CTransaction& tx : txn) {
 909                  for (const CTxIn& txin : tx.vin) {
 910                      if (exists(txin.prevout.hash)) continue;
 911                      pvNoSpendsRemaining->push_back(txin.prevout);
 912                  }
 913              }
 914          }
 915      }
 916  
 917      if (maxFeeRateRemoved > CFeeRate(0)) {
 918          LogDebug(BCLog::MEMPOOL, "Removed %u txn, rolling minimum fee bumped to %s\n", nTxnRemoved, maxFeeRateRemoved.ToString());
 919      }
 920  }
 921  
 922  std::tuple<size_t, size_t, CAmount> CTxMemPool::CalculateAncestorData(const CTxMemPoolEntry& entry) const
 923  {
 924      auto ancestors = m_txgraph->GetAncestors(entry, TxGraph::Level::MAIN);
 925  
 926      size_t ancestor_count = ancestors.size();
 927      size_t ancestor_size = 0;
 928      CAmount ancestor_fees = 0;
 929      for (auto tx: ancestors) {
 930          const CTxMemPoolEntry& anc = static_cast<const CTxMemPoolEntry&>(*tx);
 931          ancestor_size += anc.GetTxSize();
 932          ancestor_fees += anc.GetModifiedFee();
 933      }
 934      return {ancestor_count, ancestor_size, ancestor_fees};
 935  }
 936  
 937  std::tuple<size_t, size_t, CAmount> CTxMemPool::CalculateDescendantData(const CTxMemPoolEntry& entry) const
 938  {
 939      auto descendants = m_txgraph->GetDescendants(entry, TxGraph::Level::MAIN);
 940      size_t descendant_count = descendants.size();
 941      size_t descendant_size = 0;
 942      CAmount descendant_fees = 0;
 943  
 944      for (auto tx: descendants) {
 945          const CTxMemPoolEntry &desc = static_cast<const CTxMemPoolEntry&>(*tx);
 946          descendant_size += desc.GetTxSize();
 947          descendant_fees += desc.GetModifiedFee();
 948      }
 949      return {descendant_count, descendant_size, descendant_fees};
 950  }
 951  
 952  void CTxMemPool::GetTransactionAncestry(const Txid& txid, size_t& ancestors, size_t& cluster_count, size_t* const ancestorsize, CAmount* const ancestorfees) const {
 953      LOCK(cs);
 954      auto it = mapTx.find(txid);
 955      ancestors = cluster_count = 0;
 956      if (it != mapTx.end()) {
 957          auto [ancestor_count, ancestor_size, ancestor_fees] = CalculateAncestorData(*it);
 958          ancestors = ancestor_count;
 959          if (ancestorsize) *ancestorsize = ancestor_size;
 960          if (ancestorfees) *ancestorfees = ancestor_fees;
 961          cluster_count = m_txgraph->GetCluster(*it, TxGraph::Level::MAIN).size();
 962      }
 963  }
 964  
 965  bool CTxMemPool::GetLoadTried() const
 966  {
 967      LOCK(cs);
 968      return m_load_tried;
 969  }
 970  
 971  void CTxMemPool::SetLoadTried(bool load_tried)
 972  {
 973      LOCK(cs);
 974      m_load_tried = load_tried;
 975  }
 976  
 977  std::vector<CTxMemPool::txiter> CTxMemPool::GatherClusters(const std::vector<Txid>& txids) const
 978  {
 979      AssertLockHeld(cs);
 980  
 981      std::vector<CTxMemPool::txiter> ret;
 982      std::set<const CTxMemPoolEntry*> unique_cluster_representatives;
 983      for (auto txid : txids) {
 984          auto it = mapTx.find(txid);
 985          if (it != mapTx.end()) {
 986              // Note that TxGraph::GetCluster will return results in graph
 987              // order, which is deterministic (as long as we are not modifying
 988              // the graph).
 989              auto cluster = m_txgraph->GetCluster(*it, TxGraph::Level::MAIN);
 990              if (unique_cluster_representatives.insert(static_cast<const CTxMemPoolEntry*>(&(**cluster.begin()))).second) {
 991                  for (auto tx : cluster) {
 992                      ret.emplace_back(mapTx.iterator_to(static_cast<const CTxMemPoolEntry&>(*tx)));
 993                  }
 994              }
 995          }
 996      }
 997      if (ret.size() > 500) {
 998          return {};
 999      }
1000      return ret;
1001  }
1002  
1003  util::Result<std::pair<std::vector<FeeFrac>, std::vector<FeeFrac>>> CTxMemPool::ChangeSet::CalculateChunksForRBF()
1004  {
1005      LOCK(m_pool->cs);
1006  
1007      if (!CheckMemPoolPolicyLimits()) {
1008          return util::Error{Untranslated("cluster size limit exceeded")};
1009      }
1010  
1011      return m_pool->m_txgraph->GetMainStagingDiagrams();
1012  }
1013  
1014  CTxMemPool::ChangeSet::TxHandle CTxMemPool::ChangeSet::StageAddition(const CTransactionRef& tx, const CAmount fee, int64_t time, unsigned int entry_height, uint64_t entry_sequence, bool spends_coinbase, int64_t sigops_cost, LockPoints lp)
1015  {
1016      LOCK(m_pool->cs);
1017      Assume(m_to_add.find(tx->GetHash()) == m_to_add.end());
1018      Assume(!m_dependencies_processed);
1019  
1020      // We need to process dependencies after adding a new transaction.
1021      m_dependencies_processed = false;
1022  
1023      CAmount delta{0};
1024      m_pool->ApplyDelta(tx->GetHash(), delta);
1025  
1026      FeePerWeight feerate(fee, GetSigOpsAdjustedWeight(GetTransactionWeight(*tx), sigops_cost, ::nBytesPerSigOp));
1027      auto newit = m_to_add.emplace(tx, fee, time, entry_height, entry_sequence, spends_coinbase, sigops_cost, lp).first;
1028      m_pool->m_txgraph->AddTransaction(const_cast<CTxMemPoolEntry&>(*newit), feerate);
1029      if (delta) {
1030          newit->UpdateModifiedFee(delta);
1031          m_pool->m_txgraph->SetTransactionFee(*newit, newit->GetModifiedFee());
1032      }
1033  
1034      m_entry_vec.push_back(newit);
1035  
1036      return newit;
1037  }
1038  
1039  void CTxMemPool::ChangeSet::StageRemoval(CTxMemPool::txiter it)
1040  {
1041      LOCK(m_pool->cs);
1042      m_pool->m_txgraph->RemoveTransaction(*it);
1043      m_to_remove.insert(it);
1044  }
1045  
1046  void CTxMemPool::ChangeSet::Apply()
1047  {
1048      LOCK(m_pool->cs);
1049      if (!m_dependencies_processed) {
1050          ProcessDependencies();
1051      }
1052      m_pool->Apply(this);
1053      m_to_add.clear();
1054      m_to_remove.clear();
1055      m_entry_vec.clear();
1056      m_ancestors.clear();
1057  }
1058  
1059  void CTxMemPool::ChangeSet::ProcessDependencies()
1060  {
1061      LOCK(m_pool->cs);
1062      Assume(!m_dependencies_processed); // should only call this once.
1063      for (const auto& entryptr : m_entry_vec) {
1064          for (const auto &txin : entryptr->GetSharedTx()->vin) {
1065              std::optional<txiter> piter = m_pool->GetIter(txin.prevout.hash);
1066              if (!piter) {
1067                  auto it = m_to_add.find(txin.prevout.hash);
1068                  if (it != m_to_add.end()) {
1069                      piter = std::make_optional(it);
1070                  }
1071              }
1072              if (piter) {
1073                  m_pool->m_txgraph->AddDependency(/*parent=*/**piter, /*child=*/*entryptr);
1074              }
1075          }
1076      }
1077      m_dependencies_processed = true;
1078      return;
1079   }
1080  
1081  bool CTxMemPool::ChangeSet::CheckMemPoolPolicyLimits()
1082  {
1083      LOCK(m_pool->cs);
1084      if (!m_dependencies_processed) {
1085          ProcessDependencies();
1086      }
1087  
1088      return !m_pool->m_txgraph->IsOversized(TxGraph::Level::TOP);
1089  }
1090  
1091  std::vector<FeePerWeight> CTxMemPool::GetFeerateDiagram() const
1092  {
1093      FeePerWeight zero{};
1094      std::vector<FeePerWeight> ret;
1095  
1096      ret.emplace_back(zero);
1097  
1098      StartBlockBuilding();
1099  
1100      std::vector<CTxMemPoolEntry::CTxMemPoolEntryRef> dummy;
1101  
1102      FeePerWeight last_selection = GetBlockBuilderChunk(dummy);
1103      while (last_selection != FeePerWeight{}) {
1104          last_selection += ret.back();
1105          ret.emplace_back(last_selection);
1106          IncludeBuilderChunk();
1107          last_selection = GetBlockBuilderChunk(dummy);
1108      }
1109      StopBlockBuilding();
1110      return ret;
1111  }
1112