diff --git a/OpenRA.Game/Actor.cs b/OpenRA.Game/Actor.cs
index bf211ac472..869cc6ab65 100644
--- a/OpenRA.Game/Actor.cs
+++ b/OpenRA.Game/Actor.cs
@@ -24,6 +24,13 @@ namespace OpenRA
 {
 	public sealed class Actor : IScriptBindable, IScriptNotifyBind, ILuaTableBinding, ILuaEqualityBinding, ILuaToStringBinding, IEquatable<Actor>, IDisposable
 	{
+		internal struct SyncHash
+		{
+			public readonly ISync Trait;
+			public readonly int Hash;
+			public SyncHash(ISync trait, int hash) { Trait = trait; Hash = hash; }
+		}
+
 		public readonly ActorInfo Info;
 
 		public readonly World World;
@@ -62,6 +69,8 @@ namespace OpenRA
 			}
 		}
 
+		internal IEnumerable<SyncHash> SyncHashes { get; private set; }
+
 		readonly IFacing facing;
 		readonly IHealth health;
 		readonly IRenderModifier[] renderModifiers;
@@ -112,6 +121,12 @@ namespace OpenRA
 			visibilityModifiers = TraitsImplementing<IVisibilityModifier>().ToArray();
 			defaultVisibility = Trait<IDefaultVisibility>();
 			Targetables = TraitsImplementing<ITargetable>().ToArray();
+
+			SyncHashes =
+				TraitsImplementing<ISync>()
+				.Select(sync => Pair.New(sync, Sync.GetHashFunction(sync)))
+				.ToArray()
+				.Select(pair => new SyncHash(pair.First, pair.Second(pair.First)));
 		}
 
 		Rectangle DetermineBounds()
diff --git a/OpenRA.Game/Network/SyncReport.cs b/OpenRA.Game/Network/SyncReport.cs
index c3a2f0fbd3..2917ba9b78 100644
--- a/OpenRA.Game/Network/SyncReport.cs
+++ b/OpenRA.Game/Network/SyncReport.cs
@@ -63,31 +63,29 @@ namespace OpenRA.Network
 			report.SyncedRandom = orderManager.World.SharedRandom.Last;
 			report.TotalCount = orderManager.World.SharedRandom.TotalCount;
 			report.Traits.Clear();
-			foreach (var a in orderManager.World.ActorsWithTrait<ISync>())
-			{
-				var sync = Sync.CalculateSyncHash(a.Trait);
-				if (sync != 0)
-					report.Traits.Add(new TraitReport()
-					{
-						ActorID = a.Actor.ActorID,
-						Type = a.Actor.Info.Name,
-						Owner = (a.Actor.Owner == null) ? "null" : a.Actor.Owner.PlayerName,
-						Trait = a.Trait.GetType().Name,
-						Hash = sync,
-						NamesValues = DumpSyncTrait(a.Trait)
-					});
-			}
+			foreach (var actor in orderManager.World.ActorsHavingTrait<ISync>())
+				foreach (var syncHash in actor.SyncHashes)
+					if (syncHash.Hash != 0)
+						report.Traits.Add(new TraitReport()
+						{
+							ActorID = actor.ActorID,
+							Type = actor.Info.Name,
+							Owner = (actor.Owner == null) ? "null" : actor.Owner.PlayerName,
+							Trait = syncHash.Trait.GetType().Name,
+							Hash = syncHash.Hash,
+							NamesValues = DumpSyncTrait(syncHash.Trait)
+						});
 
 			foreach (var e in orderManager.World.Effects)
 			{
 				var sync = e as ISync;
 				if (sync != null)
 				{
-					var hash = Sync.CalculateSyncHash(sync);
+					var hash = Sync.Hash(sync);
 					if (hash != 0)
 						report.Effects.Add(new EffectReport()
 						{
-							Name = sync.ToString().Split('.').Last(),
+							Name = sync.GetType().Name,
 							Hash = hash,
 							NamesValues = DumpSyncTrait(sync)
 						});
diff --git a/OpenRA.Game/Sync.cs b/OpenRA.Game/Sync.cs
index 9492016424..733be00eae 100644
--- a/OpenRA.Game/Sync.cs
+++ b/OpenRA.Game/Sync.cs
@@ -26,24 +26,29 @@ namespace OpenRA
 
 	public static class Sync
 	{
-		static Cache<Type, Func<object, int>> hashFuncCache = new Cache<Type, Func<object, int>>(t => GenerateHashFunc(t));
+		static readonly ConcurrentCache<Type, Func<object, int>> HashFunctions =
+			new ConcurrentCache<Type, Func<object, int>>(GenerateHashFunc);
 
-		public static int CalculateSyncHash(object obj)
+		internal static Func<object, int> GetHashFunction(ISync sync)
 		{
-			return hashFuncCache[obj.GetType()](obj);
+			return HashFunctions[sync.GetType()];
 		}
 
-		static Dictionary<Type, MethodInfo> hashFunctions = new Dictionary<Type, MethodInfo>()
+		internal static int Hash(ISync sync)
+		{
+			return GetHashFunction(sync)(sync);
+		}
+
+		static readonly Dictionary<Type, MethodInfo> CustomHashFunctions = new Dictionary<Type, MethodInfo>()
 		{
 			{ typeof(int2), ((Func<int2, int>)HashInt2).Method },
 			{ typeof(CPos), ((Func<CPos, int>)HashCPos).Method },
 			{ typeof(CVec), ((Func<CVec, int>)HashCVec).Method },
-			{ typeof(WDist), ((Func<WDist, int>)Hash).Method },
-			{ typeof(WPos), ((Func<WPos, int>)Hash).Method },
-			{ typeof(WVec), ((Func<WVec, int>)Hash).Method },
-			{ typeof(WAngle), ((Func<WAngle, int>)Hash).Method },
-			{ typeof(WRot), ((Func<WRot, int>)Hash).Method },
-			{ typeof(TypeDictionary), ((Func<TypeDictionary, int>)HashTDict).Method },
+			{ typeof(WDist), ((Func<WDist, int>)HashUsingHashCode).Method },
+			{ typeof(WPos), ((Func<WPos, int>)HashUsingHashCode).Method },
+			{ typeof(WVec), ((Func<WVec, int>)HashUsingHashCode).Method },
+			{ typeof(WAngle), ((Func<WAngle, int>)HashUsingHashCode).Method },
+			{ typeof(WRot), ((Func<WRot, int>)HashUsingHashCode).Method },
 			{ typeof(Actor), ((Func<Actor, int>)HashActor).Method },
 			{ typeof(Player), ((Func<Player, int>)HashPlayer).Method },
 			{ typeof(Target), ((Func<Target, int>)HashTarget).Method },
@@ -51,8 +56,8 @@ namespace OpenRA
 
 		static void EmitSyncOpcodes(Type type, ILGenerator il)
 		{
-			if (hashFunctions.ContainsKey(type))
-				il.EmitCall(OpCodes.Call, hashFunctions[type], null);
+			if (CustomHashFunctions.ContainsKey(type))
+				il.EmitCall(OpCodes.Call, CustomHashFunctions[type], null);
 			else if (type == typeof(bool))
 			{
 				var l = il.DefineLabel();
@@ -62,15 +67,13 @@ namespace OpenRA
 				il.Emit(OpCodes.Ldc_I4, 0x555);
 				il.MarkLabel(l);
 			}
-			else if (type.HasAttribute<SyncAttribute>())
-				il.EmitCall(OpCodes.Call, ((Func<object, int>)CalculateSyncHash).Method, null);
 			else if (type != typeof(int))
 				throw new NotImplementedException("SyncAttribute on member of unhashable type: {0}".F(type.FullName));
 
 			il.Emit(OpCodes.Xor);
 		}
 
-		public static Func<object, int> GenerateHashFunc(Type t)
+		static Func<object, int> GenerateHashFunc(Type t)
 		{
 			var d = new DynamicMethod("hash_{0}".F(t.Name), typeof(int), new Type[] { typeof(object) }, t);
 			var il = d.GetILGenerator();
@@ -116,14 +119,6 @@ namespace OpenRA
 			return ((i2.X * 5) ^ (i2.Y * 3)) / 4;
 		}
 
-		public static int HashTDict(TypeDictionary d)
-		{
-			var ret = 0;
-			foreach (var o in d)
-				ret += CalculateSyncHash(o);
-			return ret;
-		}
-
 		public static int HashActor(Actor a)
 		{
 			if (a != null)
@@ -152,7 +147,7 @@ namespace OpenRA
 					return (int)(t.FrozenActor.Actor.ActorID << 16) * 0x567;
 
 				case TargetType.Terrain:
-					return Hash(t.CenterPosition);
+					return HashUsingHashCode(t.CenterPosition);
 
 				default:
 				case TargetType.Invalid:
@@ -160,7 +155,7 @@ namespace OpenRA
 			}
 		}
 
-		public static int Hash<T>(T t)
+		public static int HashUsingHashCode<T>(T t)
 		{
 			return t.GetHashCode();
 		}
diff --git a/OpenRA.Game/World.cs b/OpenRA.Game/World.cs
index 1a9149346d..b37f5c4448 100644
--- a/OpenRA.Game/World.cs
+++ b/OpenRA.Game/World.cs
@@ -341,18 +341,19 @@ namespace OpenRA
 
 				// hash all the actors
 				foreach (var a in Actors)
-					ret += n++ * (int)(1 + a.ActorID) * Sync.CalculateSyncHash(a);
+					ret += n++ * (int)(1 + a.ActorID) * Sync.HashActor(a);
 
 				// hash all the traits that tick
-				foreach (var x in ActorsWithTrait<ISync>())
-					ret += n++ * (int)(1 + x.Actor.ActorID) * Sync.CalculateSyncHash(x.Trait);
+				foreach (var actor in ActorsHavingTrait<ISync>())
+					foreach (var syncHash in actor.SyncHashes)
+						ret += n++ * (int)(1 + actor.ActorID) * syncHash.Hash;
 
 				// TODO: don't go over all effects
 				foreach (var e in Effects)
 				{
 					var sync = e as ISync;
 					if (sync != null)
-						ret += n++ * Sync.CalculateSyncHash(sync);
+						ret += n++ * Sync.Hash(sync);
 				}
 
 				// Hash the shared rng
diff --git a/OpenRA.Mods.Common/Traits/Player/MissionObjectives.cs b/OpenRA.Mods.Common/Traits/Player/MissionObjectives.cs
index f50eb657cc..54176d24e7 100644
--- a/OpenRA.Mods.Common/Traits/Player/MissionObjectives.cs
+++ b/OpenRA.Mods.Common/Traits/Player/MissionObjectives.cs
@@ -63,7 +63,7 @@ namespace OpenRA.Mods.Common.Traits
 			{
 				var hash = 0;
 				foreach (var objective in objectives)
-					hash ^= Sync.Hash(objective.State);
+					hash ^= Sync.HashUsingHashCode(objective.State);
 				return hash;
 			}
 		}