diff --git a/src/main.cpp b/src/main.cpp index 7f408c4d1..06957ba52 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -3235,18 +3235,6 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv) } } - // Ask the first connected node for block updates - static int nAskedForBlocks = 0; - if (!pfrom->fClient && !pfrom->fOneShot && !fImporting && !fReindex && - (pfrom->nStartingHeight > (nBestHeight - 144)) && - (pfrom->nVersion < NOBLKS_VERSION_START || - pfrom->nVersion >= NOBLKS_VERSION_END) && - (nAskedForBlocks < 1 || vNodes.size() <= 1)) - { - nAskedForBlocks++; - pfrom->PushGetBlocks(pindexBest, uint256(0)); - } - // Relay alerts { LOCK(cs_mapAlerts); @@ -3855,6 +3843,12 @@ bool SendMessages(CNode* pto, bool fSendTrickle) pto->PushMessage("ping"); } + // Start block sync + if (pto->fStartSync && !fImporting && !fReindex) { + pto->fStartSync = false; + pto->PushGetBlocks(pindexBest, uint256(0)); + } + // Resend wallet transactions that haven't gotten in a block yet // Except during reindex, importing and IBD, when old wallet // transactions become unconfirmed and spams other nodes. diff --git a/src/net.cpp b/src/net.cpp index 0defa96e4..4727f1e2e 100644 --- a/src/net.cpp +++ b/src/net.cpp @@ -44,6 +44,7 @@ static map mapLocalHost; static bool vfReachable[NET_MAX] = {}; static bool vfLimited[NET_MAX] = {}; static CNode* pnodeLocalHost = NULL; +static CNode* pnodeSync = NULL; uint64 nLocalHostNonce = 0; static std::vector vhListenSocket; CAddrMan addrman; @@ -521,12 +522,16 @@ void CNode::CloseSocketDisconnect() printf("disconnecting node %s\n", addrName.c_str()); closesocket(hSocket); hSocket = INVALID_SOCKET; - - // in case this fails, we'll empty the recv buffer when the CNode is deleted - TRY_LOCK(cs_vRecvMsg, lockRecv); - if (lockRecv) - vRecvMsg.clear(); } + + // in case this fails, we'll empty the recv buffer when the CNode is deleted + TRY_LOCK(cs_vRecvMsg, lockRecv); + if (lockRecv) + vRecvMsg.clear(); + + // if this was the sync node, we'll need a new one + if (this == pnodeSync) + pnodeSync = NULL; } void CNode::Cleanup() @@ -1546,24 +1551,64 @@ bool OpenNetworkConnection(const CAddress& addrConnect, CSemaphoreGrant *grantOu } +// for now, use a very simple selection metric: the node from which we received +// most recently +double static NodeSyncScore(const CNode *pnode) { + return -pnode->nLastRecv; +} +void static StartSync(const vector &vNodes) { + CNode *pnodeNewSync = NULL; + double dBestScore = 0; + // fImporting and fReindex are accessed out of cs_main here, but only + // as an optimization - they are checked again in SendMessages. + if (fImporting || fReindex) + return; - + // Iterate over all nodes + BOOST_FOREACH(CNode* pnode, vNodes) { + // check preconditions for allowing a sync + if (!pnode->fClient && !pnode->fOneShot && + !pnode->fDisconnect && pnode->fSuccessfullyConnected && + (pnode->nStartingHeight > (nBestHeight - 144)) && + (pnode->nVersion < NOBLKS_VERSION_START || pnode->nVersion >= NOBLKS_VERSION_END)) { + // if ok, compare node's score with the best so far + double dScore = NodeSyncScore(pnode); + if (pnodeNewSync == NULL || dScore > dBestScore) { + pnodeNewSync = pnode; + dBestScore = dScore; + } + } + } + // if a new sync candidate was found, start sync! + if (pnodeNewSync) { + pnodeNewSync->fStartSync = true; + pnodeSync = pnodeNewSync; + } +} void ThreadMessageHandler() { SetThreadPriority(THREAD_PRIORITY_BELOW_NORMAL); while (true) { + bool fHaveSyncNode = false; + vector vNodesCopy; { LOCK(cs_vNodes); vNodesCopy = vNodes; - BOOST_FOREACH(CNode* pnode, vNodesCopy) + BOOST_FOREACH(CNode* pnode, vNodesCopy) { pnode->AddRef(); + if (pnode == pnodeSync) + fHaveSyncNode = true; + } } + if (!fHaveSyncNode) + StartSync(vNodesCopy); + // Poll the connected nodes for messages CNode* pnodeTrickle = NULL; if (!vNodesCopy.empty()) diff --git a/src/net.h b/src/net.h index 30b9ac866..2a8b7f09e 100644 --- a/src/net.h +++ b/src/net.h @@ -202,6 +202,7 @@ public: CBlockIndex* pindexLastGetBlocksBegin; uint256 hashLastGetBlocksEnd; int nStartingHeight; + bool fStartSync; // flood relay std::vector vAddrToSend; @@ -242,6 +243,7 @@ public: pindexLastGetBlocksBegin = 0; hashLastGetBlocksEnd = 0; nStartingHeight = -1; + fStartSync = false; fGetAddr = false; nMisbehavior = 0; fRelayTxes = false;