implement medium congestion indication

libi2pd/I2NPProtocol.cpp

@@ -376,7 +376,7 @@ namespace i2p
 				if (!i2p::context.DecryptTunnelBuildRecord (record + BUILD_REQUEST_RECORD_ENCRYPTED_OFFSET, clearText)) return false;
 				uint8_t retCode = 0;
 				// replace record to reply
-				if (i2p::context.AcceptsTunnels () && !i2p::context.IsHighCongestion ())
+				if (i2p::context.AcceptsTunnels () && i2p::context.GetCongestionLevel (false) < 100)
 				{
 					auto transitTunnel = i2p::tunnel::CreateTransitTunnel (
 							bufbe32toh (clearText + ECIES_BUILD_REQUEST_RECORD_RECEIVE_TUNNEL_OFFSET),
@@ -586,7 +586,7 @@ namespace i2p
 				// check if we accept this tunnel
 				std::shared_ptr<i2p::tunnel::TransitTunnel> transitTunnel;
 				uint8_t retCode = 0;
-				if (!i2p::context.AcceptsTunnels () || i2p::context.IsHighCongestion ())
+				if (!i2p::context.AcceptsTunnels () || i2p::context.GetCongestionLevel (false) >= 100)
 					retCode = 30;
 				if (!retCode)
 				{

libi2pd/RouterContext.cpp

@@ -1137,11 +1137,12 @@ namespace i2p
 		return i2p::tunnel::tunnels.GetExploratoryPool ();
 	}
 
-	bool RouterContext::IsHighCongestion () const
+	int RouterContext::GetCongestionLevel (bool longTerm) const
 	{
-		return i2p::tunnel::tunnels.IsTooManyTransitTunnels () ||
+		return std::max (
-			i2p::transport::transports.IsBandwidthExceeded () ||
+			i2p::tunnel::tunnels.GetCongestionLevel (),
-			i2p::transport::transports.IsTransitBandwidthExceeded ();
+			i2p::transport::transports.GetCongestionLevel (longTerm)
+		);
 	}
 	
 	void RouterContext::HandleI2NPMessage (const uint8_t * buf, size_t len)
@@ -1447,10 +1448,16 @@ namespace i2p
 		if (ecode != boost::asio::error::operation_aborted)
 		{
 			auto c = i2p::data::RouterInfo::eLowCongestion;
-			if (!AcceptsTunnels ()) 
+			if (!AcceptsTunnels () || m_ShareRatio == 0)
 				c = i2p::data::RouterInfo::eRejectAll;
-			else if (IsHighCongestion ()) 
+			else
-				c = i2p::data::RouterInfo::eHighCongestion;
+			{
+				int congestionLevel = GetCongestionLevel (true);
+				if (congestionLevel > 90)
+					c = i2p::data::RouterInfo::eHighCongestion;
+				else if (congestionLevel > 70)
+					c = i2p::data::RouterInfo::eMediumCongestion;
+			}
 			if (m_RouterInfo.UpdateCongestion (c))
 				UpdateRouterInfo ();
 			ScheduleCongestionUpdate ();

libi2pd/RouterContext.h

@@ -167,7 +167,7 @@ namespace garlic
 			void SetShareRatio (int percents); // 0 - 100
 			bool AcceptsTunnels () const { return m_AcceptsTunnels; };
 			void SetAcceptsTunnels (bool acceptsTunnels) { m_AcceptsTunnels = acceptsTunnels; };
-			bool IsHighCongestion () const;
+			int GetCongestionLevel (bool longTerm) const;
 			bool SupportsV6 () const { return m_RouterInfo.IsV6 (); };
 			bool SupportsV4 () const { return m_RouterInfo.IsV4 (); };
 			bool SupportsMesh () const { return m_RouterInfo.IsMesh (); };

libi2pd/Transports.cpp

@@ -140,10 +140,8 @@ namespace transport
 		m_X25519KeysPairSupplier (15), // 15 pre-generated keys
 		m_TotalSentBytes (0), m_TotalReceivedBytes (0), m_TotalTransitTransmittedBytes (0),
 		m_InBandwidth (0), m_OutBandwidth (0), m_TransitBandwidth (0),
-		m_LastInBandwidthUpdateBytes (0), m_LastOutBandwidthUpdateBytes (0), m_LastTransitBandwidthUpdateBytes (0),
 		m_InBandwidth15s (0), m_OutBandwidth15s (0), m_TransitBandwidth15s (0),
-		m_LastInBandwidth15sUpdateBytes (0), m_LastOutBandwidth15sUpdateBytes (0), m_LastTransitBandwidth15sUpdateBytes (0),
+		m_InBandwidth5m (0), m_OutBandwidth5m (0), m_TransitBandwidth5m (0)
-		m_LastBandwidth15sUpdateTime (0)
 	{
 	}
 
@@ -306,6 +304,16 @@ namespace transport
 		m_PeerCleanupTimer->expires_from_now (boost::posix_time::seconds(5 * SESSION_CREATION_TIMEOUT));
 		m_PeerCleanupTimer->async_wait (std::bind (&Transports::HandlePeerCleanupTimer, this, std::placeholders::_1));
 
+		uint64_t ts = i2p::util::GetMillisecondsSinceEpoch();
+		for (int i = 0; i < TRAFFIC_SAMPLE_COUNT; i++)
+		{
+			m_TrafficSamples[i].Timestamp = ts - (TRAFFIC_SAMPLE_COUNT - i - 1) * 1000;
+			m_TrafficSamples[i].TotalReceivedBytes = 0;
+			m_TrafficSamples[i].TotalSentBytes = 0;
+			m_TrafficSamples[i].TotalTransitTransmittedBytes = 0;
+		}
+		m_TrafficSamplePtr = TRAFFIC_SAMPLE_COUNT - 1;
+
 		m_UpdateBandwidthTimer->expires_from_now (boost::posix_time::seconds(1));
 		m_UpdateBandwidthTimer->async_wait (std::bind (&Transports::HandleUpdateBandwidthTimer, this, std::placeholders::_1));
 
@@ -364,51 +372,62 @@ namespace transport
 		}
 	}
 
+	void Transports::UpdateBandwidthValues(int interval, uint32_t& in, uint32_t& out, uint32_t& transit)
+	{
+		TrafficSample& sample1 = m_TrafficSamples[m_TrafficSamplePtr];
+		TrafficSample& sample2 = m_TrafficSamples[(TRAFFIC_SAMPLE_COUNT + m_TrafficSamplePtr - interval) % TRAFFIC_SAMPLE_COUNT];
+		auto delta = sample1.Timestamp - sample2.Timestamp;
+		in = (sample1.TotalReceivedBytes - sample2.TotalReceivedBytes) * 1000 / delta;
+		out = (sample1.TotalSentBytes - sample2.TotalSentBytes) * 1000 / delta;
+		transit = (sample1.TotalTransitTransmittedBytes - sample2.TotalTransitTransmittedBytes) * 1000 / delta;
+	}
+
 	void Transports::HandleUpdateBandwidthTimer (const boost::system::error_code& ecode)
 	{
 		if (ecode != boost::asio::error::operation_aborted)
 		{
-			uint64_t ts = i2p::util::GetMillisecondsSinceEpoch ();
+			m_TrafficSamplePtr++;
-
+			if (m_TrafficSamplePtr == TRAFFIC_SAMPLE_COUNT)
-			// updated every second
+				m_TrafficSamplePtr = 0;
-			m_InBandwidth = m_TotalReceivedBytes - m_LastInBandwidthUpdateBytes;
-			m_OutBandwidth = m_TotalSentBytes - m_LastOutBandwidthUpdateBytes;
-			m_TransitBandwidth = m_TotalTransitTransmittedBytes - m_LastTransitBandwidthUpdateBytes;
 
-			m_LastInBandwidthUpdateBytes = m_TotalReceivedBytes;
+			TrafficSample& sample = m_TrafficSamples[m_TrafficSamplePtr];
-			m_LastOutBandwidthUpdateBytes = m_TotalSentBytes;
+			sample.Timestamp = i2p::util::GetMillisecondsSinceEpoch();
-			m_LastTransitBandwidthUpdateBytes = m_TotalTransitTransmittedBytes;
+			sample.TotalReceivedBytes = m_TotalReceivedBytes;
+			sample.TotalSentBytes = m_TotalSentBytes;
+			sample.TotalTransitTransmittedBytes = m_TotalTransitTransmittedBytes;
 
-			// updated every 15 seconds
+			UpdateBandwidthValues (1, m_InBandwidth, m_OutBandwidth, m_TransitBandwidth);
-			auto delta = ts - m_LastBandwidth15sUpdateTime;
+			UpdateBandwidthValues (15, m_InBandwidth15s, m_OutBandwidth15s, m_TransitBandwidth15s);
-			if (delta > 15 * 1000)
+			UpdateBandwidthValues (300, m_InBandwidth5m, m_OutBandwidth5m, m_TransitBandwidth5m);
-			{
-				m_InBandwidth15s = (m_TotalReceivedBytes - m_LastInBandwidth15sUpdateBytes) * 1000 / delta;
-				m_OutBandwidth15s = (m_TotalSentBytes - m_LastOutBandwidth15sUpdateBytes) * 1000 / delta;
-				m_TransitBandwidth15s = (m_TotalTransitTransmittedBytes - m_LastTransitBandwidth15sUpdateBytes) * 1000 / delta;
-
-				m_LastBandwidth15sUpdateTime = ts;
-				m_LastInBandwidth15sUpdateBytes = m_TotalReceivedBytes;
-				m_LastOutBandwidth15sUpdateBytes = m_TotalSentBytes;
-				m_LastTransitBandwidth15sUpdateBytes = m_TotalTransitTransmittedBytes;
-			}
 
 			m_UpdateBandwidthTimer->expires_from_now (boost::posix_time::seconds(1));
 			m_UpdateBandwidthTimer->async_wait (std::bind (&Transports::HandleUpdateBandwidthTimer, this, std::placeholders::_1));
 		}
 	}
 
-	bool Transports::IsBandwidthExceeded () const
+	int Transports::GetCongestionLevel (bool longTerm) const
 	{
-		auto limit = i2p::context.GetBandwidthLimit() * 1024; // convert to bytes
+		auto bwLimit = i2p::context.GetBandwidthLimit () * 1024; // convert to bytes
-		auto bw = std::max (m_InBandwidth15s, m_OutBandwidth15s);
+		auto tbwLimit = i2p::context.GetTransitBandwidthLimit () * 1024; // convert to bytes
-		return bw > limit;
-	}
 
-	bool Transports::IsTransitBandwidthExceeded () const
+		if (tbwLimit == 0 || bwLimit == 0)
-	{
+			return 100;
-		auto limit = i2p::context.GetTransitBandwidthLimit() * 1024; // convert to bytes
+
-		return m_TransitBandwidth > limit;
+		uint32_t bw;
+		uint32_t tbw;
+		if (longTerm)
+		{
+			bw = std::max (m_InBandwidth5m, m_OutBandwidth5m);
+			tbw = m_TransitBandwidth5m;
+		}
+		else
+		{
+			bw = std::max (m_InBandwidth15s, m_OutBandwidth15s);
+			tbw = m_TransitBandwidth;
+		}
+		auto bwCongestionLevel = 100 * bw / bwLimit;
+		auto tbwCongestionLevel = 100 * tbw / tbwLimit;
+		return std::max (bwCongestionLevel, tbwCongestionLevel);
 	}
 
 	void Transports::SendMessage (const i2p::data::IdentHash& ident, std::shared_ptr<i2p::I2NPMessage> msg)

libi2pd/Transports.h

@@ -114,6 +114,17 @@ namespace transport
 	const int PEER_TEST_DELAY_INTERVAL_VARIANCE = 30; // in milliseconds
 	const int MAX_NUM_DELAYED_MESSAGES = 150;
 	const int CHECK_PROFILE_NUM_DELAYED_MESSAGES = 15; // check profile after
+
+	const int TRAFFIC_SAMPLE_COUNT = 301; // seconds
+
+	struct TrafficSample
+	{
+		uint64_t Timestamp;
+		uint64_t TotalReceivedBytes;
+		uint64_t TotalSentBytes;
+		uint64_t TotalTransitTransmittedBytes;
+	};
+
 	class Transports
 	{
 		public:
@@ -153,8 +164,7 @@ namespace transport
 			uint32_t GetInBandwidth15s () const { return m_InBandwidth15s; };
 			uint32_t GetOutBandwidth15s () const { return m_OutBandwidth15s; };
 			uint32_t GetTransitBandwidth15s () const { return m_TransitBandwidth15s; };
-			bool IsBandwidthExceeded () const;
+			int GetCongestionLevel (bool longTerm) const;
-			bool IsTransitBandwidthExceeded () const;
 			size_t GetNumPeers () const { return m_Peers.size (); };
 			std::shared_ptr<const i2p::data::RouterInfo> GetRandomPeer (bool isHighBandwidth) const;
 
@@ -186,6 +196,7 @@ namespace transport
 			void HandlePeerCleanupTimer (const boost::system::error_code& ecode);
 			void HandlePeerTestTimer (const boost::system::error_code& ecode);
 			void HandleUpdateBandwidthTimer (const boost::system::error_code& ecode);
+			void UpdateBandwidthValues (int interval, uint32_t& in, uint32_t& out, uint32_t& transit);
 
 			void DetectExternalIP ();
 
@@ -210,14 +221,15 @@ namespace transport
 
 			std::atomic<uint64_t> m_TotalSentBytes, m_TotalReceivedBytes, m_TotalTransitTransmittedBytes;
 
+			TrafficSample m_TrafficSamples[TRAFFIC_SAMPLE_COUNT];
+			int m_TrafficSamplePtr;
+
 			// Bandwidth per second
 			uint32_t m_InBandwidth, m_OutBandwidth, m_TransitBandwidth;
-			uint64_t m_LastInBandwidthUpdateBytes, m_LastOutBandwidthUpdateBytes, m_LastTransitBandwidthUpdateBytes;
+			// Bandwidth during last 15 seconds
-
-			// Bandwidth every 15 seconds
 			uint32_t m_InBandwidth15s, m_OutBandwidth15s, m_TransitBandwidth15s;
-			uint64_t m_LastInBandwidth15sUpdateBytes, m_LastOutBandwidth15sUpdateBytes, m_LastTransitBandwidth15sUpdateBytes;
+			// Bandwidth during last 5 minutes
-			uint64_t m_LastBandwidth15sUpdateTime;
+			uint32_t m_InBandwidth5m, m_OutBandwidth5m, m_TransitBandwidth5m;
 
 			/** which router families to trust for first hops */
 			std::vector<i2p::data::FamilyID> m_TrustedFamilies;

libi2pd/Tunnel.h

@@ -240,7 +240,7 @@ namespace tunnel
 
 			void SetMaxNumTransitTunnels (uint16_t maxNumTransitTunnels);
 			uint16_t GetMaxNumTransitTunnels () const { return m_MaxNumTransitTunnels; };
-			bool IsTooManyTransitTunnels () const { return m_TransitTunnels.size () >= m_MaxNumTransitTunnels; };
+			int GetCongestionLevel() const { return 100 * m_TransitTunnels.size() / m_MaxNumTransitTunnels; }
 
 		private: