diff options
Diffstat (limited to 'src/net.cpp')
| -rw-r--r-- | src/net.cpp | 23 |
1 files changed, 19 insertions, 4 deletions
diff --git a/src/net.cpp b/src/net.cpp index 707412bb32..2ccb89248f 100644 --- a/src/net.cpp +++ b/src/net.cpp @@ -53,10 +53,17 @@ static constexpr std::chrono::minutes DUMP_PEERS_INTERVAL{15}; static constexpr int DNSSEEDS_TO_QUERY_AT_ONCE = 3; /** How long to delay before querying DNS seeds + * + * If we have more than THRESHOLD entries in addrman, then it's likely + * that we got those addresses from having previously connected to the P2P + * network, and that we'll be able to successfully reconnect to the P2P + * network via contacting one of them. So if that's the case, spend a + * little longer trying to connect to known peers before querying the + * DNS seeds. */ -static constexpr std::chrono::seconds DNSSEEDS_DELAY_FEW_PEERS{11}; // 11sec -static constexpr std::chrono::seconds DNSSEEDS_DELAY_MANY_PEERS{300}; // 5min -static constexpr int DNSSEEDS_DELAY_PEER_THRESHOLD = 1000; // "many" vs "few" peers -- you should only get this many if you've been on the live network +static constexpr std::chrono::seconds DNSSEEDS_DELAY_FEW_PEERS{11}; +static constexpr std::chrono::minutes DNSSEEDS_DELAY_MANY_PEERS{5}; +static constexpr int DNSSEEDS_DELAY_PEER_THRESHOLD = 1000; // "many" vs "few" peers // We add a random period time (0 to 1 seconds) to feeler connections to prevent synchronization. #define FEELER_SLEEP_WINDOW 1 @@ -1595,6 +1602,8 @@ void CConnman::ThreadDNSAddressSeed() seeds_right_now = seeds.size(); } else if (addrman.size() == 0) { // If we have no known peers, query all. + // This will occur on the first run, or if peers.dat has been + // deleted. seeds_right_now = seeds.size(); } @@ -1620,6 +1629,9 @@ void CConnman::ThreadDNSAddressSeed() LogPrintf("Waiting %d seconds before querying DNS seeds.\n", seeds_wait_time.count()); std::chrono::seconds to_wait = seeds_wait_time; while (to_wait.count() > 0) { + // if sleeping for the MANY_PEERS interval, wake up + // early to see if we have enough peers and can stop + // this thread entirely freeing up its resources std::chrono::seconds w = std::min(DNSSEEDS_DELAY_FEW_PEERS, to_wait); if (!interruptNet.sleep_for(w)) return; to_wait -= w; @@ -1646,7 +1658,7 @@ void CConnman::ThreadDNSAddressSeed() if (interruptNet) return; - // hold off on querying seeds if p2p network deactivated + // hold off on querying seeds if P2P network deactivated if (!fNetworkActive) { LogPrintf("Waiting for network to be reactivated before querying DNS seeds.\n"); do { @@ -1797,6 +1809,9 @@ void CConnman::ThreadOpenConnections(const std::vector<std::string> connect) return; // Add seed nodes if DNS seeds are all down (an infrastructure attack?). + // Note that we only do this if we started with an empty peers.dat, + // (in which case we will query DNS seeds immediately) *and* the DNS + // seeds have not returned any results. if (addrman.size() == 0 && (GetTime() - nStart > 60)) { static bool done = false; if (!done) { |