diff --git a/src/net.cpp b/src/net.cpp index 258599747a..077a51bac3 100644 --- a/src/net.cpp +++ b/src/net.cpp @@ -1693,6 +1693,36 @@ void CConnman::ProcessOneShot() } } +bool CConnman::GetTryNewOutboundPeer() +{ + return m_try_another_outbound_peer; +} + +void CConnman::SetTryNewOutboundPeer(bool flag) +{ + m_try_another_outbound_peer = flag; +} + +// Return the number of peers we have over our outbound connection limit +// Exclude peers that are marked for disconnect, or are going to be +// disconnected soon (eg one-shots and feelers) +// Also exclude peers that haven't finished initial connection handshake yet +// (so that we don't decide we're over our desired connection limit, and then +// evict some peer that has finished the handshake) +int CConnman::GetExtraOutboundCount() +{ + int nOutbound = 0; + { + LOCK(cs_vNodes); + for (CNode* pnode : vNodes) { + if (!pnode->fInbound && !pnode->m_manual_connection && !pnode->fFeeler && !pnode->fDisconnect && !pnode->fOneShot && pnode->fSuccessfullyConnected) { + ++nOutbound; + } + } + } + return std::max(nOutbound - nMaxOutbound, 0); +} + void CConnman::ThreadOpenConnections(const std::vector connect) { // Connect to specific addresses @@ -1781,7 +1811,8 @@ void CConnman::ThreadOpenConnections(const std::vector connect) // * Only make a feeler connection once every few minutes. // bool fFeeler = false; - if (nOutbound >= nMaxOutbound) { + + if (nOutbound >= nMaxOutbound && !GetTryNewOutboundPeer()) { int64_t nTime = GetTimeMicros(); // The current time right now (in microseconds). if (nTime > nNextFeeler) { nNextFeeler = PoissonNextSend(nTime, FEELER_INTERVAL); @@ -2204,6 +2235,7 @@ CConnman::CConnman(uint64_t nSeed0In, uint64_t nSeed1In) : nSeed0(nSeed0In), nSe semOutbound = nullptr; semAddnode = nullptr; flagInterruptMsgProc = false; + SetTryNewOutboundPeer(false); Options connOptions; Init(connOptions); diff --git a/src/net.h b/src/net.h index f373ab0cf1..c90df64992 100644 --- a/src/net.h +++ b/src/net.h @@ -251,6 +251,19 @@ public: void GetBanned(banmap_t &banmap); void SetBanned(const banmap_t &banmap); + // This allows temporarily exceeding nMaxOutbound, with the goal of finding + // a peer that is better than all our current peers. + void SetTryNewOutboundPeer(bool flag); + bool GetTryNewOutboundPeer(); + + // Return the number of outbound peers we have in excess of our target (eg, + // if we previously called SetTryNewOutboundPeer(true), and have since set + // to false, we may have extra peers that we wish to disconnect). This may + // return a value less than (num_outbound_connections - num_outbound_slots) + // in cases where some outbound connections are not yet fully connected, or + // not yet fully disconnected. + int GetExtraOutboundCount(); + bool AddNode(const std::string& node); bool RemoveAddedNode(const std::string& node); std::vector GetAddedNodeInfo(); @@ -413,6 +426,11 @@ private: std::thread threadOpenAddedConnections; std::thread threadOpenConnections; std::thread threadMessageHandler; + + /** flag for deciding to connect to an extra outbound peer, + * in excess of nMaxOutbound + * This takes the place of a feeler connection */ + std::atomic_bool m_try_another_outbound_peer; }; extern std::unique_ptr g_connman; void Discover(boost::thread_group& threadGroup);