fix(core): Caches DateTime.NowUtc (#548)

- [X] Caches DateTime.NowUtc on the game loop (not other threads)
- [X] Replaces all locations where it makes sense
- [X] Adds Min/Max for `IComparable` (TimeSpan, DateTimes, etc)

Closes #261

Projects/Server/Items/Item.cs

@@ -955,7 +955,7 @@ namespace Server
 
             /* begin last moved time optimization */
             var ticks = LastMoved.Ticks;
-            var now = DateTime.UtcNow.Ticks;
+            var now = Core.Now.Ticks;
 
             var minutes = new TimeSpan(now - ticks).TotalMinutes;
 
@@ -2280,7 +2280,7 @@ namespace Server
 
         public void SetLastMoved()
         {
-            LastMoved = DateTime.UtcNow;
+            LastMoved = Core.Now;
         }
 
         public virtual bool CanStackWith(Item dropped) =>
@@ -2598,11 +2598,11 @@ namespace Server
 
                             try
                             {
-                                LastMoved = DateTime.UtcNow - TimeSpan.FromMinutes(minutes);
+                                LastMoved = Core.Now - TimeSpan.FromMinutes(minutes);
                             }
                             catch
                             {
-                                LastMoved = DateTime.UtcNow;
+                                LastMoved = Core.Now;
                             }
                         }
 

Projects/Server/Main.cs

@@ -37,8 +37,8 @@ namespace Server
         private static string _baseDirectory;
 
         private static bool _profiling;
-        private static DateTime _profileStart;
-        private static TimeSpan _profileTime;
+        private static long _profileStart;
+        private static long _profileTime;
 #nullable enable
         private static bool? _isRunningFromXUnit;
 #nullable restore
@@ -95,19 +95,17 @@ namespace Server
 
                 _profiling = value;
 
-                if (_profileStart > DateTime.MinValue)
+                if (_profileStart > 0)
                 {
-                    _profileTime += DateTime.UtcNow - _profileStart;
+                    _profileTime += TickCount - _profileStart;
                 }
 
-                _profileStart = _profiling ? DateTime.UtcNow : DateTime.MinValue;
+                _profileStart = _profiling ? TickCount : 0;
             }
         }
 
         public static TimeSpan ProfileTime =>
-            _profileStart > DateTime.MinValue
-                ? _profileTime + (DateTime.UtcNow - _profileStart)
-                : _profileTime;
+            TimeSpan.FromMilliseconds(_profileStart > 0 ? _profileTime + (TickCount - _profileStart) : _profileTime);
 
         public static Assembly Assembly { get; set; }
 
@@ -118,7 +116,11 @@ namespace Server
 
         public static Thread Thread { get; private set; }
 
-        [ThreadStatic] private static long _tickCount;
+        [ThreadStatic]
+        private static long _tickCount;
+
+        [ThreadStatic]
+        private static DateTime _now;
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         private static long GetTicks() => 1000L * Stopwatch.GetTimestamp() / Stopwatch.Frequency;
@@ -129,6 +131,12 @@ namespace Server
             set => _tickCount = value;
         }
 
+        public static DateTime Now
+        {
+            get => _now == DateTime.MinValue ? DateTime.UtcNow : _now;
+            set => _now = value;
+        }
+
         public static bool MultiProcessor { get; private set; }
 
         public static int ProcessorCount { get; private set; }
@@ -488,6 +496,7 @@ namespace Server
                 while (!Closing)
                 {
                     _tickCount = TickCount;
+                    _now = DateTime.UtcNow;
 
                     var events = Mobile.ProcessDeltaQueue();
                     events += Item.ProcessDeltaQueue();
@@ -502,6 +511,7 @@ namespace Server
                     events += _eventLoopContext.ExecuteTasks();
 
                     _tickCount = 0;
+                    _now = DateTime.MinValue;
 
                     if (events > 0)
                     {

Projects/Server/Mobiles/AggressorInfo.cs

@@ -38,7 +38,7 @@ namespace Server
                     DumpAccess();
                 }
 
-                return m_Attacker.Deleted || m_Defender.Deleted || DateTime.UtcNow >= m_LastCombatTime + ExpireDelay;
+                return m_Attacker.Deleted || m_Defender.Deleted || Core.Now >= m_LastCombatTime + ExpireDelay;
             }
         }
 
@@ -200,7 +200,7 @@ namespace Server
                 DumpAccess();
             }
 
-            m_LastCombatTime = DateTime.UtcNow;
+            m_LastCombatTime = Core.Now;
             m_Reported = false;
         }
     }

Projects/Server/Mobiles/Mobile.cs

@@ -34,7 +34,7 @@ namespace Server
         private readonly DateTime m_Expire;
 
         public TimedSkillMod(SkillName skill, bool relative, double value, TimeSpan delay)
-            : this(skill, relative, value, DateTime.UtcNow + delay)
+            : this(skill, relative, value, Core.Now + delay)
         {
         }
 
@@ -42,7 +42,7 @@ namespace Server
             : base(skill, relative, value) =>
             m_Expire = expire;
 
-        public override bool CheckCondition() => DateTime.UtcNow < m_Expire;
+        public override bool CheckCondition() => Core.Now < m_Expire;
     }
 
     public class EquippedSkillMod : SkillMod
@@ -240,7 +240,7 @@ namespace Server
             Name = name;
             Offset = offset;
             m_Duration = duration;
-            m_Added = DateTime.UtcNow;
+            m_Added = Core.Now;
         }
 
         public StatType Type { get; }
@@ -249,15 +249,7 @@ namespace Server
 
         public int Offset { get; }
 
-        public bool HasElapsed()
-        {
-            if (m_Duration == TimeSpan.Zero)
-            {
-                return false;
-            }
-
-            return DateTime.UtcNow - m_Added >= m_Duration;
-        }
+        public bool HasElapsed() => m_Duration != TimeSpan.Zero && Core.Now - m_Added >= m_Duration;
     }
 
     public class DamageEntry
@@ -270,7 +262,7 @@ namespace Server
 
         public DateTime LastDamage { get; set; }
 
-        public bool HasExpired => DateTime.UtcNow > LastDamage + ExpireDelay;
+        public bool HasExpired => Core.Now > LastDamage + ExpireDelay;
 
         public List<DamageEntry> Responsible { get; set; }
 
@@ -3747,7 +3739,7 @@ namespace Server
                 return;
             }
 
-            var now = DateTime.UtcNow;
+            var now = Core.Now;
             var next = m_NextWarmodeChange;
 
             if (now > next || m_WarmodeChanges == 0)
@@ -5996,7 +5988,7 @@ namespace Server
             var de = FindDamageEntryFor(from) ?? new DamageEntry(from);
 
             de.DamageGiven += amount;
-            de.LastDamage = DateTime.UtcNow;
+            de.LastDamage = Core.Now;
 
             DamageEntries.Remove(de);
             DamageEntries.Add(de);
@@ -6028,7 +6020,7 @@ namespace Server
                 }
 
                 resp.DamageGiven += amount;
-                resp.LastDamage = DateTime.UtcNow;
+                resp.LastDamage = Core.Now;
             }
 
             return de;
@@ -7925,7 +7917,7 @@ namespace Server
             DamageEntries = new List<DamageEntry>();
 
             NextSkillTime = Core.TickCount;
-            CreationTime = DateTime.UtcNow;
+            CreationTime = Core.Now;
         }
 
         public virtual void Delta(MobileDelta flag)

Projects/Server/Network/NetState/NetState.cs

@@ -148,14 +148,14 @@ namespace Server.Network
                 _toString = "(error)";
             }
 
-            ConnectedOn = DateTime.UtcNow;
+            ConnectedOn = Core.Now;
 
             CreatedCallback?.Invoke(this);
         }
 
         public DateTime ConnectedOn { get; }
 
-        public TimeSpan ConnectedFor => DateTime.UtcNow - ConnectedOn;
+        public TimeSpan ConnectedFor => Core.Now - ConnectedOn;
 
         public IPAddress Address { get; }
 
@@ -1034,7 +1034,7 @@ namespace Server.Network
             try
             {
                 using var op = new StreamWriter("network-errors.log", true);
-                op.WriteLine("# {0}", DateTime.UtcNow);
+                op.WriteLine("# {0}", Core.Now);
 
                 op.WriteLine(ex);
 
@@ -1083,7 +1083,7 @@ namespace Server.Network
             try
             {
                 using StreamWriter op = new StreamWriter("network-disconnects.log", true);
-                op.WriteLine($"# {DateTime.UtcNow}");
+                op.WriteLine($"# {Core.Now}");
 
                 op.WriteLine($"NetState: {ip}");
                 op.WriteLine(reason);

Projects/Server/Network/Packets/IncomingAccountPackets.cs

@@ -33,7 +33,7 @@ namespace Server.Network
 
             public AuthIDPersistence(ClientVersion v)
             {
-                Age = DateTime.UtcNow;
+                Age = Core.Now;
                 Version = v;
             }
         }

Projects/Server/Network/Packets/OutgoingPlayerPackets.cs

@@ -326,9 +326,8 @@ namespace Server.Network
             ns.Send(writer.Span);
         }
 
-        // TODO: Use DateTime caching against core loop
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void SendCurrentTime(this NetState ns) => ns.SendCurrentTime(DateTime.UtcNow);
+        public static void SendCurrentTime(this NetState ns) => ns.SendCurrentTime(Core.Now);
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static void SendCurrentTime(this NetState ns, DateTime date) =>

Projects/Server/Serialization/BufferWriter.cs

@@ -205,6 +205,8 @@ namespace Server
             Write(ticks);
         }
 
+        // TODO: Find a way to speed this up.
+        // Maybe used a special cached value?
         public void WriteDeltaTime(DateTime value)
         {
             var ticks = (value.Kind switch

Projects/Server/Serialization/Persistence.cs

@@ -84,14 +84,14 @@ namespace Server
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static void WriteConsole(string message)
         {
-            var now = DateTime.UtcNow;
+            var now = Core.Now;
             Console.Write("[{0} {1}] Persistence: {2}", now.ToShortDateString(), now.ToLongTimeString(), message);
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static void WriteConsoleLine(string message)
         {
-            var now = DateTime.UtcNow;
+            var now = Core.Now;
             Console.WriteLine("[{0} {1}] Persistence: {2}", now.ToShortDateString(), now.ToLongTimeString(), message);
         }
 
@@ -100,7 +100,7 @@ namespace Server
             try
             {
                 using var op = new StreamWriter("save-errors.log", true);
-                op.WriteLine("# {0}", DateTime.UtcNow);
+                op.WriteLine("# {0}", Core.Now);
 
                 op.WriteLine(ex);
 

Projects/Server/Targeting/Target.cs

@@ -19,7 +19,7 @@ namespace Server.Targeting
             CheckLOS = true;
         }
 
-        public DateTime TimeoutTime { get; private set; }
+        public long TimeoutTime { get; private set; }
 
         public bool CheckLOS { get; set; }
 
@@ -41,13 +41,13 @@ namespace Server.Targeting
             m.Target?.OnTargetCancel(m, TargetCancelType.Canceled);
         }
 
-        public void BeginTimeout(Mobile from, TimeSpan delay)
+        public void BeginTimeout(Mobile from, long delay)
         {
-            TimeoutTime = DateTime.UtcNow + delay;
+            TimeoutTime = Core.TickCount + delay;
 
             m_TimeoutTimer?.Stop();
 
-            m_TimeoutTimer = new TimeoutTimer(this, from, delay);
+            m_TimeoutTimer = new TimeoutTimer(this, from, TimeSpan.FromMilliseconds(delay));
             m_TimeoutTimer.Start();
         }
 

Projects/Server/TileMatrix/TileMatrix.cs

@@ -390,10 +390,10 @@ namespace Server
             }
             catch (EndOfStreamException ex)
             {
-                if (DateTime.UtcNow >= m_NextStaticWarning)
+                if (Core.Now >= m_NextStaticWarning)
                 {
                     Console.WriteLine("Warning: Static EOS for {0} ({1}, {2})", _map, x, y);
-                    m_NextStaticWarning = DateTime.UtcNow + TimeSpan.FromMinutes(1.0);
+                    m_NextStaticWarning = Core.Now + TimeSpan.FromMinutes(1.0);
                 }
 
                 return _emptyStaticBlock;
@@ -438,10 +438,10 @@ namespace Server
             }
             catch (Exception ex)
             {
-                if (DateTime.UtcNow >= m_NextLandWarning)
+                if (Core.Now >= m_NextLandWarning)
                 {
                     Console.WriteLine("Warning: Land EOS for {0} ({1}, {2})", _map, x, y);
-                    m_NextLandWarning = DateTime.UtcNow + TimeSpan.FromMinutes(1.0);
+                    m_NextLandWarning = Core.Now + TimeSpan.FromMinutes(1.0);
                 }
 
                 return _invalidLandBlock;

Projects/Server/Utilities/Utility.cs

@@ -1338,7 +1338,10 @@ namespace Server
             val.CompareTo(max) > 0 ? max : val;
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static TimeSpan Max(this TimeSpan val, TimeSpan max) => val > max ? max : val;
+        public static T Min<T>(T val, T min) where T : IComparable<T> => val.CompareTo(min) < 0 ? val : min;
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static T Max<T>(T val, T max) where T : IComparable<T> => val.CompareTo(max) > 0 ? val : max;
 
         public static string TrimMultiline(this string str, string lineSeparator = "\n")
         {
@@ -1434,6 +1437,6 @@ namespace Server
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static string GetTimeStamp() => DateTime.UtcNow.ToString("yyyy-MM-dd-HH-mm-ss");
+        public static string GetTimeStamp() => Core.Now.ToString("yyyy-MM-dd-HH-mm-ss");
     }
 }