diff options
| -rw-r--r-- | src/net_processing.cpp | 39 |
1 files changed, 33 insertions, 6 deletions
diff --git a/src/net_processing.cpp b/src/net_processing.cpp index 74d1bf44d2..1a81c500c8 100644 --- a/src/net_processing.cpp +++ b/src/net_processing.cpp @@ -369,6 +369,9 @@ struct Peer { /** Set of txids to reconsider once their parent transactions have been accepted **/ std::set<uint256> m_orphan_work_set GUARDED_BY(g_cs_orphans); + /** Whether we've sent this peer a getheaders in response to an inv prior to initial-headers-sync completing */ + bool m_inv_triggered_getheaders_before_sync{false}; + /** Protects m_getdata_requests **/ Mutex m_getdata_requests_mutex; /** Work queue of items requested by this peer **/ @@ -681,6 +684,9 @@ private: /** Number of nodes with fSyncStarted. */ int nSyncStarted GUARDED_BY(cs_main) = 0; + /** Hash of the last block we received via INV */ + uint256 m_last_block_inv_triggering_headers_sync{}; + /** * Sources of received blocks, saved to be able punish them when processing * happens afterwards. @@ -3239,8 +3245,9 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type, UpdateBlockAvailability(pfrom.GetId(), inv.hash); if (!fAlreadyHave && !fImporting && !fReindex && !IsBlockRequested(inv.hash)) { // Headers-first is the primary method of announcement on - // the network. If a node fell back to sending blocks by inv, - // it's probably for a re-org. The final block hash + // the network. If a node fell back to sending blocks by + // inv, it may be for a re-org, or because we haven't + // completed initial headers sync. The final block hash // provided should be the highest, so send a getheaders and // then fetch the blocks we need to catch up. best_block = &inv.hash; @@ -3265,10 +3272,30 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type, } if (best_block != nullptr) { - if (MaybeSendGetHeaders(pfrom, m_chainman.ActiveChain().GetLocator(m_chainman.m_best_header), *peer)) { - LogPrint(BCLog::NET, "getheaders (%d) %s to peer=%d\n", - m_chainman.m_best_header->nHeight, best_block->ToString(), - pfrom.GetId()); + // If we haven't started initial headers-sync with this peer, then + // consider sending a getheaders now. On initial startup, there's a + // reliability vs bandwidth tradeoff, where we are only trying to do + // initial headers sync with one peer at a time, with a long + // timeout (at which point, if the sync hasn't completed, we will + // disconnect the peer and then choose another). In the meantime, + // as new blocks are found, we are willing to add one new peer per + // block to sync with as well, to sync quicker in the case where + // our initial peer is unresponsive (but less bandwidth than we'd + // use if we turned on sync with all peers). + CNodeState& state{*Assert(State(pfrom.GetId()))}; + if (state.fSyncStarted || (!peer->m_inv_triggered_getheaders_before_sync && *best_block != m_last_block_inv_triggering_headers_sync)) { + if (MaybeSendGetHeaders(pfrom, m_chainman.ActiveChain().GetLocator(m_chainman.m_best_header), *peer)) { + LogPrint(BCLog::NET, "getheaders (%d) %s to peer=%d\n", + m_chainman.m_best_header->nHeight, best_block->ToString(), + pfrom.GetId()); + } + if (!state.fSyncStarted) { + peer->m_inv_triggered_getheaders_before_sync = true; + // Update the last block hash that triggered a new headers + // sync, so that we don't turn on headers sync with more + // than 1 new peer every new block. + m_last_block_inv_triggering_headers_sync = *best_block; + } } } |