diff --git a/src/net_processing.cpp b/src/net_processing.cpp index 0e222bdfa..17e8578f5 100644 --- a/src/net_processing.cpp +++ b/src/net_processing.cpp @@ -69,6 +69,7 @@ struct COrphanTx { CTransactionRef tx; NodeId fromPeer; int64_t nTimeExpire; + size_t list_pos; }; CCriticalSection g_cs_orphans; std::map mapOrphanTransactions GUARDED_BY(g_cs_orphans); @@ -170,6 +171,8 @@ namespace { }; std::map::iterator, IteratorComparator>> mapOrphanTransactionsByPrev GUARDED_BY(g_cs_orphans); + std::vector::iterator> g_orphan_list GUARDED_BY(g_cs_orphans); //! For random eviction + static size_t vExtraTxnForCompactIt GUARDED_BY(g_cs_orphans) = 0; static std::vector> vExtraTxnForCompact GUARDED_BY(g_cs_orphans); } // namespace @@ -706,8 +709,9 @@ bool AddOrphanTx(const CTransactionRef& tx, NodeId peer) EXCLUSIVE_LOCKS_REQUIRE return false; } - auto ret = mapOrphanTransactions.emplace(hash, COrphanTx{tx, peer, GetTime() + ORPHAN_TX_EXPIRE_TIME}); + auto ret = mapOrphanTransactions.emplace(hash, COrphanTx{tx, peer, GetTime() + ORPHAN_TX_EXPIRE_TIME, g_orphan_list.size()}); assert(ret.second); + g_orphan_list.push_back(ret.first); for (const CTxIn& txin : tx->vin) { mapOrphanTransactionsByPrev[txin.prevout].insert(ret.first); } @@ -733,6 +737,18 @@ int static EraseOrphanTx(uint256 hash) EXCLUSIVE_LOCKS_REQUIRED(g_cs_orphans) if (itPrev->second.empty()) mapOrphanTransactionsByPrev.erase(itPrev); } + + size_t old_pos = it->second.list_pos; + assert(g_orphan_list[old_pos] == it); + if (old_pos + 1 != g_orphan_list.size()) { + // Unless we're deleting the last entry in g_orphan_list, move the last + // entry to the position we're deleting. + auto it_last = g_orphan_list.back(); + g_orphan_list[old_pos] = it_last; + it_last->second.list_pos = old_pos; + } + g_orphan_list.pop_back(); + mapOrphanTransactions.erase(it); return 1; } @@ -783,11 +799,8 @@ unsigned int LimitOrphanTxSize(unsigned int nMaxOrphans) while (mapOrphanTransactions.size() > nMaxOrphans) { // Evict a random orphan: - uint256 randomhash = rng.rand256(); - std::map::iterator it = mapOrphanTransactions.lower_bound(randomhash); - if (it == mapOrphanTransactions.end()) - it = mapOrphanTransactions.begin(); - EraseOrphanTx(it->first); + size_t randompos = rng.randrange(g_orphan_list.size()); + EraseOrphanTx(g_orphan_list[randompos]->first); ++nEvicted; } return nEvicted;