diff options
Diffstat (limited to 'src/net.cpp')
| -rw-r--r-- | src/net.cpp | 63 |
1 files changed, 53 insertions, 10 deletions
diff --git a/src/net.cpp b/src/net.cpp index 8fbd8fd192..c5b080f794 100644 --- a/src/net.cpp +++ b/src/net.cpp @@ -43,6 +43,9 @@ // Dump addresses to peers.dat and banlist.dat every 15 minutes (900s) #define DUMP_ADDRESSES_INTERVAL 900 +// We add a random period time (0 to 1 seconds) to feeler connections to prevent synchronization. +#define FEELER_SLEEP_WINDOW 1 + #if !defined(HAVE_MSG_NOSIGNAL) && !defined(MSG_NOSIGNAL) #define MSG_NOSIGNAL 0 #endif @@ -61,6 +64,7 @@ namespace { const int MAX_OUTBOUND_CONNECTIONS = 8; + const int MAX_FEELER_CONNECTIONS = 1; struct ListenSocket { SOCKET socket; @@ -217,7 +221,7 @@ void AdvertiseLocal(CNode *pnode) } if (addrLocal.IsRoutable()) { - LogPrintf("AdvertiseLocal: advertising address %s\n", addrLocal.ToString()); + LogPrint("net", "AdvertiseLocal: advertising address %s\n", addrLocal.ToString()); pnode->PushAddress(addrLocal); } } @@ -1017,7 +1021,8 @@ static void AcceptConnection(const ListenSocket& hListenSocket) { SOCKET hSocket = accept(hListenSocket.socket, (struct sockaddr*)&sockaddr, &len); CAddress addr; int nInbound = 0; - int nMaxInbound = nMaxConnections - MAX_OUTBOUND_CONNECTIONS; + int nMaxInbound = nMaxConnections - (MAX_OUTBOUND_CONNECTIONS + MAX_FEELER_CONNECTIONS); + assert(nMaxInbound > 0); if (hSocket != INVALID_SOCKET) if (!addr.SetSockAddr((const struct sockaddr*)&sockaddr)) @@ -1613,6 +1618,9 @@ void ThreadOpenConnections() // Initiate network connections int64_t nStart = GetTime(); + + // Minimum time before next feeler connection (in microseconds). + int64_t nNextFeeler = PoissonNextSend(nStart*1000*1000, FEELER_INTERVAL); while (true) { ProcessOneShot(); @@ -1652,13 +1660,36 @@ void ThreadOpenConnections() } } } + assert(nOutbound <= (MAX_OUTBOUND_CONNECTIONS + MAX_FEELER_CONNECTIONS)); - int64_t nANow = GetAdjustedTime(); + // Feeler Connections + // + // Design goals: + // * Increase the number of connectable addresses in the tried table. + // + // Method: + // * Choose a random address from new and attempt to connect to it if we can connect + // successfully it is added to tried. + // * Start attempting feeler connections only after node finishes making outbound + // connections. + // * Only make a feeler connection once every few minutes. + // + bool fFeeler = false; + if (nOutbound >= MAX_OUTBOUND_CONNECTIONS) { + int64_t nTime = GetTimeMicros(); // The current time right now (in microseconds). + if (nTime > nNextFeeler) { + nNextFeeler = PoissonNextSend(nTime, FEELER_INTERVAL); + fFeeler = true; + } else { + continue; + } + } + int64_t nANow = GetAdjustedTime(); int nTries = 0; while (true) { - CAddrInfo addr = addrman.Select(); + CAddrInfo addr = addrman.Select(fFeeler); // if we selected an invalid address, restart if (!addr.IsValid() || setConnected.count(addr.GetGroup()) || IsLocal(addr)) @@ -1682,7 +1713,7 @@ void ThreadOpenConnections() if (nANow - addr.nLastTry < 600 && nTries < 30) continue; - // only consider nodes missing relevant services after 40 failed attemps + // only consider nodes missing relevant services after 40 failed attempts if ((addr.nServices & nRelevantServices) != nRelevantServices && nTries < 40) continue; @@ -1694,8 +1725,17 @@ void ThreadOpenConnections() break; } - if (addrConnect.IsValid()) - OpenNetworkConnection(addrConnect, (int)setConnected.size() >= std::min(nMaxConnections - 1, 2), &grant); + if (addrConnect.IsValid()) { + + if (fFeeler) { + // Add small amount of random noise before connection to avoid synchronization. + int randsleep = GetRandInt(FEELER_SLEEP_WINDOW * 1000); + MilliSleep(randsleep); + LogPrint("net", "Making feeler connection to %s\n", addrConnect.ToString()); + } + + OpenNetworkConnection(addrConnect, (int)setConnected.size() >= std::min(nMaxConnections - 1, 2), &grant, NULL, false, fFeeler); + } } } @@ -1777,7 +1817,7 @@ void ThreadOpenAddedConnections() } // if successful, this moves the passed grant to the constructed node -bool OpenNetworkConnection(const CAddress& addrConnect, bool fCountFailure, CSemaphoreGrant *grantOutbound, const char *pszDest, bool fOneShot) +bool OpenNetworkConnection(const CAddress& addrConnect, bool fCountFailure, CSemaphoreGrant *grantOutbound, const char *pszDest, bool fOneShot, bool fFeeler) { // // Initiate outbound network connection @@ -1801,6 +1841,8 @@ bool OpenNetworkConnection(const CAddress& addrConnect, bool fCountFailure, CSem pnode->fNetworkNode = true; if (fOneShot) pnode->fOneShot = true; + if (fFeeler) + pnode->fFeeler = true; return true; } @@ -2062,7 +2104,7 @@ void StartNode(boost::thread_group& threadGroup, CScheduler& scheduler) if (semOutbound == NULL) { // initialize semaphore - int nMaxOutbound = std::min(MAX_OUTBOUND_CONNECTIONS, nMaxConnections); + int nMaxOutbound = std::min((MAX_OUTBOUND_CONNECTIONS + MAX_FEELER_CONNECTIONS), nMaxConnections); semOutbound = new CSemaphore(nMaxOutbound); } @@ -2107,7 +2149,7 @@ bool StopNode() LogPrintf("StopNode()\n"); MapPort(false); if (semOutbound) - for (int i=0; i<MAX_OUTBOUND_CONNECTIONS; i++) + for (int i=0; i<(MAX_OUTBOUND_CONNECTIONS + MAX_FEELER_CONNECTIONS); i++) semOutbound->post(); if (fAddressesInitialized) @@ -2448,6 +2490,7 @@ CNode::CNode(SOCKET hSocketIn, const CAddress& addrIn, const std::string& addrNa fWhitelisted = false; fOneShot = false; fClient = false; // set by version message + fFeeler = false; fInbound = fInboundIn; fNetworkNode = false; fSuccessfullyConnected = false; 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