From f2f8313b42c72f580cca4d9fb99961dbc0ee3493 Mon Sep 17 00:00:00 2001
From: Kamron Batman <3953314+kamronbatman@users.noreply.github.com>
Date: Sun, 23 Aug 2026 12:40:03 -0700
Subject: [PATCH] perf: cache the resolved speed entry per creature

Serialization consults the speed table four times per mob per save (the
Should* flag checks) and again through the Default* methods on elided
loads - each a SpeedClass/type dictionary walk. The resolved
SpeedClassEntry is now cached on the creature (one reference; the table
is immutable after Configure), so those become a null-check and field
reads. GetSpeeds/GetMoveSpeeds stay the virtual override point, so
stubs and forks that override them still steer elision; only their
default implementations read the cache. NPCSpeeds' per-call lookups
collapse into FindEntry.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 Projects/UOContent/Mobiles/BaseCreature.cs | 19 ++++++++++++++--
 Projects/UOContent/Mobiles/NPCSpeeds.cs    | 25 +++++-----------------
 2 files changed, 22 insertions(+), 22 deletions(-)

diff --git a/Projects/UOContent/Mobiles/BaseCreature.cs b/Projects/UOContent/Mobiles/BaseCreature.cs
index 0713fd531..efe0eb646 100644
--- a/Projects/UOContent/Mobiles/BaseCreature.cs
+++ b/Projects/UOContent/Mobiles/BaseCreature.cs
@@ -5078,14 +5078,29 @@ namespace Server.Mobiles
         // If this needs to be serialized, recommend creating a hash or registry id. Don't serialize strings.
         public virtual SpeedLevel SpeedClass => SpeedLevel.None;
 
+        // Resolved once per creature; serialization consults the table four times per mob
+        // per save (and again on elided loads), so the dictionary walk must not repeat.
+        private NPCSpeeds.SpeedClassEntry _speedEntry;
+
+        private NPCSpeeds.SpeedClassEntry SpeedEntry => _speedEntry ??= NPCSpeeds.FindEntry(this);
+
         public virtual void GetSpeeds(out double activeSpeed, out double passiveSpeed)
         {
-            NPCSpeeds.GetSpeeds(this, out activeSpeed, out passiveSpeed);
+            var entry = SpeedEntry ?? throw new InvalidOperationException(
+                $"{GetType()} has no speed entry - is {"Data/npc-speeds.json"} missing?"
+            );
+
+            activeSpeed = entry.ActiveSpeed;
+            passiveSpeed = entry.PassiveSpeed;
         }
 
+        // Move speeds are optional (0 = inherit), so this tolerates an unloaded table.
         public virtual void GetMoveSpeeds(out double activeMoveSpeed, out double passiveMoveSpeed)
         {
-            NPCSpeeds.GetMoveSpeeds(this, out activeMoveSpeed, out passiveMoveSpeed);
+            var entry = SpeedEntry;
+
+            activeMoveSpeed = entry?.ActiveMoveSpeed ?? 0;
+            passiveMoveSpeed = entry?.PassiveMoveSpeed ?? 0;
         }
 
         // Pre-v22 saves carry no movement clock. Think speeds matching today's GetSpeeds
diff --git a/Projects/UOContent/Mobiles/NPCSpeeds.cs b/Projects/UOContent/Mobiles/NPCSpeeds.cs
index 8f5e908bb..9a8785b5e 100644
--- a/Projects/UOContent/Mobiles/NPCSpeeds.cs
+++ b/Projects/UOContent/Mobiles/NPCSpeeds.cs
@@ -26,32 +26,17 @@ public static class NPCSpeeds
     public static int MinIdleSeconds { get; private set; }
     public static int MaxIdleSeconds { get; private set; }
 
-    public static void GetSpeeds(BaseCreature bc, out double activeSpeed, out double passiveSpeed)
+    // Null when the table is unloaded (test fixtures). Creatures cache the result — the
+    // table is immutable after Configure.
+    public static SpeedClassEntry FindEntry(BaseCreature bc)
     {
         if ((bc.SpeedClass == SpeedLevel.None || !_speedsByLevel.TryGetValue(bc.SpeedClass, out var sp)) &&
             !_speedsByType.TryGetValue(bc.GetType(), out sp))
         {
-            sp = _speedsByLevel[SpeedLevel.Medium];
+            _speedsByLevel.TryGetValue(SpeedLevel.Medium, out sp);
         }
 
-        activeSpeed = sp.ActiveSpeed;
-        passiveSpeed = sp.PassiveSpeed;
-    }
-
-    // Move speeds are optional (0 = inherit), so this tolerates a missing entry or table.
-    public static void GetMoveSpeeds(BaseCreature bc, out double activeMoveSpeed, out double passiveMoveSpeed)
-    {
-        if ((bc.SpeedClass == SpeedLevel.None || !_speedsByLevel.TryGetValue(bc.SpeedClass, out var sp)) &&
-            !_speedsByType.TryGetValue(bc.GetType(), out sp) &&
-            !_speedsByLevel.TryGetValue(SpeedLevel.Medium, out sp))
-        {
-            activeMoveSpeed = 0;
-            passiveMoveSpeed = 0;
-            return;
-        }
-
-        activeMoveSpeed = sp.ActiveMoveSpeed;
-        passiveMoveSpeed = sp.PassiveMoveSpeed;
+        return sp;
     }
 
     public static void RegisterSpeed(SpeedClassEntry entry)