Use Environment.TickCount instead of DateTime.UtcNow.

This should be slightly more efficient because it avoids division when converting ticks to seconds.

Author: bgrainger

src/MySqlConnector/Core/ConnectionPool.cs

@@ -130,7 +130,7 @@ private bool SessionIsHealthy(ServerSession session)
 			if (session.DatabaseOverride != null)
 				return false;
 			if (ConnectionSettings.ConnectionLifeTime > 0
-			    && (DateTime.UtcNow - session.CreatedUtc).TotalSeconds >= ConnectionSettings.ConnectionLifeTime)
+			    && unchecked((uint) Environment.TickCount) - session.CreatedTicks >= ConnectionSettings.ConnectionLifeTime)
 				return false;
 
 			return true;
@@ -178,7 +178,7 @@ public async Task ReapAsync(IOBehavior ioBehavior, CancellationToken cancellatio
 		{
 			Log.Debug("{0} reaping connection pool", m_logArguments);
 			RecoverLeakedSessions();
-			await CleanPoolAsync(ioBehavior, session => (DateTime.UtcNow - session.LastReturnedUtc).TotalSeconds >= ConnectionSettings.ConnectionIdleTimeout, true, cancellationToken).ConfigureAwait(false);
+			await CleanPoolAsync(ioBehavior, session => (unchecked((uint) Environment.TickCount) - session.LastReturnedTicks) / 1000 >= ConnectionSettings.ConnectionIdleTimeout, true, cancellationToken).ConfigureAwait(false);
 		}
 
 		/// <summary>

src/MySqlConnector/Core/ConnectionSettings.cs

@@ -40,7 +40,7 @@ public ConnectionSettings(MySqlConnectionStringBuilder csb)
 
 			// Connection Pooling Options
 			Pooling = csb.Pooling;
-			ConnectionLifeTime = (int)csb.ConnectionLifeTime;
+			ConnectionLifeTime = Math.Min(csb.ConnectionLifeTime, uint.MaxValue / 1000) * 1000;
 			ConnectionReset = csb.ConnectionReset;
 			ConnectionIdleTimeout = (int)csb.ConnectionIdleTimeout;
 			if (csb.MinimumPoolSize > csb.MaximumPoolSize)
@@ -90,7 +90,7 @@ public ConnectionSettings(MySqlConnectionStringBuilder csb)
 
 		// Connection Pooling Options
 		public bool Pooling { get; }
-		public int ConnectionLifeTime { get; }
+		public uint ConnectionLifeTime { get; }
 		public bool ConnectionReset { get; }
 		public int ConnectionIdleTimeout { get; }
 		public int MinimumPoolSize { get; }

src/MySqlConnector/Core/ServerSession.cs

@@ -34,7 +34,7 @@ public ServerSession(ConnectionPool pool, int poolGeneration, int id)
 			m_lock = new object();
 			m_payloadCache = new ArraySegmentHolder<byte>();
 			Id = (pool?.Id ?? 0) + "." + id;
-			CreatedUtc = DateTime.UtcNow;
+			CreatedTicks = unchecked((uint) Environment.TickCount);
 			Pool = pool;
 			PoolGeneration = poolGeneration;
 			HostName = "";
@@ -46,10 +46,10 @@ public ServerSession(ConnectionPool pool, int poolGeneration, int id)
 		public ServerVersion ServerVersion { get; set; }
 		public int ConnectionId { get; set; }
 		public byte[] AuthPluginData { get; set; }
-		public DateTime CreatedUtc { get; }
+		public uint CreatedTicks { get; }
 		public ConnectionPool Pool { get; }
 		public int PoolGeneration { get; }
-		public DateTime LastReturnedUtc { get; private set; }
+		public uint LastReturnedTicks { get; private set; }
 		public string DatabaseOverride { get; set; }
 		public string HostName { get; private set; }
 		public IPAddress IPAddress => (m_tcpClient?.Client.RemoteEndPoint as IPEndPoint)?.Address;
@@ -63,7 +63,7 @@ public void ReturnToPool()
 				m_logArguments[1] = Pool?.Id;
 				Log.Debug("{0} returning to Pool{1}", m_logArguments);
 			}
-			LastReturnedUtc = DateTime.UtcNow;
+			LastReturnedTicks = unchecked((uint) Environment.TickCount);
 			Pool?.Return(this);
 		}