diff --git a/AyCode.Core.Serializers.SourceGenerator/AcBinarySourceGenerator.cs b/AyCode.Core.Serializers.SourceGenerator/AcBinarySourceGenerator.cs
index 1cadf4e..46a4e92 100644
--- a/AyCode.Core.Serializers.SourceGenerator/AcBinarySourceGenerator.cs
+++ b/AyCode.Core.Serializers.SourceGenerator/AcBinarySourceGenerator.cs
@@ -636,11 +636,12 @@ public class AcBinarySourceGenerator : IIncrementalGenerator
 
         if (hasStringScan)
         {
-            // Hoist the shift once — per-property InterningFlags check uses internBit directly.
+            // Use pre-computed InternBit from context (avoids Options.UseStringInterning field chain + shift per object).
+            // Per-property InterningFlags check uses internBit directly.
             // Cannot combine flags (OR) because different properties may have different flags
             // and Attribute mode must NOT scan All-only properties.
             sb.AppendLine();
-            sb.AppendLine("        var internBit = 1 << (int)context.Options.UseStringInterning;");
+            sb.AppendLine("        var internBit = context.InternBit;");
             sb.AppendLine("        int minIntern = 0, maxIntern = 0;");
             sb.AppendLine("        if (internBit > 1) { minIntern = context.MinStringInternLength; maxIntern = context.MaxStringInternLength; }");
         }
@@ -722,7 +723,7 @@ public class AcBinarySourceGenerator : IIncrementalGenerator
                 if (p.InterningFlags == 0)
                     sb.AppendLine($"{i}context.StringInternEligible = false;");
                 else
-                    sb.AppendLine($"{i}context.StringInternEligible = ({p.InterningFlags} & (1 << (int)context.Options.UseStringInterning)) != 0;");
+                    sb.AppendLine($"{i}context.StringInternEligible = ({p.InterningFlags} & context.InternBit) != 0;");
                 sb.AppendLine($"{i}AcBinarySerializer.WriteStringGenerated({a}, context);");
                 break;
             case PropertyTypeKind.Complex:
@@ -1616,7 +1617,7 @@ public class AcBinarySourceGenerator : IIncrementalGenerator
             if (p.InterningFlags == 0)
                 sb.AppendLine($"{ii}context.StringInternEligible = false;");
             else
-                sb.AppendLine($"{ii}context.StringInternEligible = ({p.InterningFlags} & (1 << (int)context.Options.UseStringInterning)) != 0;");
+                sb.AppendLine($"{ii}context.StringInternEligible = ({p.InterningFlags} & context.InternBit) != 0;");
             sb.AppendLine($"{ii}AcBinarySerializer.WriteStringGenerated({k}, context);");
         }
         else if (IsMarkerless(p.DictKeyKind) || p.DictKeyKind == PropertyTypeKind.Enum)
@@ -1638,7 +1639,7 @@ public class AcBinarySourceGenerator : IIncrementalGenerator
             if (p.InterningFlags == 0)
                 sb.AppendLine($"{ii}    context.StringInternEligible = false;");
             else
-                sb.AppendLine($"{ii}    context.StringInternEligible = ({p.InterningFlags} & (1 << (int)context.Options.UseStringInterning)) != 0;");
+                sb.AppendLine($"{ii}    context.StringInternEligible = ({p.InterningFlags} & context.InternBit) != 0;");
             sb.AppendLine($"{ii}    AcBinarySerializer.WriteStringGenerated({v}, context);");
             sb.AppendLine($"{ii}}}");
         }
diff --git a/AyCode.Core/Serializers/AcSerializerContextBase.cs b/AyCode.Core/Serializers/AcSerializerContextBase.cs
index 574c344..71d1528 100644
--- a/AyCode.Core/Serializers/AcSerializerContextBase.cs
+++ b/AyCode.Core/Serializers/AcSerializerContextBase.cs
@@ -24,6 +24,16 @@ public abstract class AcSerializerContextBase<TMetadata, TOptions>
 
     public byte MaxDepth => Options.MaxDepth;
     public ReferenceHandlingMode ReferenceHandling => Options.ReferenceHandling;
+
+    /// <summary>
+    /// Pre-computed: ReferenceHandling != None. Avoids Options field chain per call.
+    /// </summary>
+    private bool _hasRefHandling;
+
+    /// <summary>
+    /// Pre-computed: ReferenceHandling == IId (not All). When true, only IId types are tracked.
+    /// </summary>
+    private bool _hasIdHandling;
     public bool ThrowOnCircularReference => Options.ThrowOnCircularReference;
     /// <summary>
     /// Global shared cache for metadata (thread-safe, shared across all contexts).
@@ -48,17 +58,17 @@ public abstract class AcSerializerContextBase<TMetadata, TOptions>
     /// </summary>
     protected abstract Func<Type, TMetadata> MetadataFactory { get; }
 
-    [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public bool UseTypeReferenceHandling(Type type)
-    {
-        var wrapper = GetWrapper(type);
-        return UseTypeReferenceHandling(wrapper.Metadata);
-    }
+    //[MethodImpl(MethodImplOptions.AggressiveInlining)]
+    //public bool UseTypeReferenceHandling(Type type)
+    //{
+    //    var wrapper = GetWrapper(type);
+    //    return UseTypeReferenceHandling(wrapper.Metadata);
+    //}
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public bool UseTypeReferenceHandling(TMetadata metaData)
     {
-        return ReferenceHandling != ReferenceHandlingMode.None && (metaData.IsIId || ReferenceHandling == ReferenceHandlingMode.All);
+        return _hasRefHandling && (metaData.IsIId || !_hasIdHandling);
     }
 
     #region Wrapper Access
@@ -153,6 +163,8 @@ public abstract class AcSerializerContextBase<TMetadata, TOptions>
     public virtual void Reset(TOptions options)
     {
         Options = options;
+        _hasRefHandling = options.ReferenceHandling != ReferenceHandlingMode.None;
+        _hasIdHandling = options.ReferenceHandling == ReferenceHandlingMode.OnlyId;
     }
 
     /// <summary>
diff --git a/AyCode.Core/Serializers/Binaries/AcBinarySerializer.BinarySerializationContext.cs b/AyCode.Core/Serializers/Binaries/AcBinarySerializer.BinarySerializationContext.cs
index 051193c..712df90 100644
--- a/AyCode.Core/Serializers/Binaries/AcBinarySerializer.BinarySerializationContext.cs
+++ b/AyCode.Core/Serializers/Binaries/AcBinarySerializer.BinarySerializationContext.cs
@@ -132,12 +132,15 @@ public static partial class AcBinarySerializer
 
         /// <summary>
         /// Sorts write plan by VisitIndex for sequential cursor consumption in write pass.
-        /// Called once after scan pass completes.
+        /// Called once after scan pass completes. Pre-loads first entry for TryConsumeWritePlanEntry.
         /// </summary>
         internal void SortWritePlan()
         {
             if (_writePlanCount > 1)
                 _writePlan.AsSpan(0, _writePlanCount).Sort(static (a, b) => a.VisitIndex.CompareTo(b.VisitIndex));
+
+            if (_writePlanCount > 0)
+                _nextWritePlanEntry = _writePlan![0];
         }
 
         /// <summary>Write pass cursor index into sorted _writePlan array.</summary>
@@ -146,6 +149,12 @@ public static partial class AcBinarySerializer
         /// <summary>Write pass visit counter. Mirrors ScanVisitIndex ordering.</summary>
         internal int WriteVisitIndex;
 
+        /// <summary>
+        /// Pre-loaded next write plan entry. Null when plan is empty or exhausted.
+        /// Avoids array access on hit path — entry is already cached.
+        /// </summary>
+        private WriteDuplicateEntry? _nextWritePlanEntry;
+
         /// <summary>
         /// Set per-property in WritePropertyOrSkip before calling WriteString.
         /// Controls whether the current string property participates in the cursor-based interning.
@@ -162,15 +171,14 @@ public static partial class AcBinarySerializer
         internal bool TryConsumeWritePlanEntry(out WriteDuplicateEntry entry)
         {
             var visitIndex = WriteVisitIndex++;
-            if (_writePlan != null && WritePlanCursor < _writePlanCount)
+            var next = _nextWritePlanEntry;
+            if (next != null && visitIndex == next.Value.VisitIndex)
             {
-                ref var candidate = ref _writePlan[WritePlanCursor];
-                if (candidate.VisitIndex == visitIndex)
-                {
-                    entry = candidate;
-                    WritePlanCursor++;
-                    return true;
-                }
+                entry = next.Value;
+                _nextWritePlanEntry = ++WritePlanCursor < _writePlanCount
+                    ? _writePlan![WritePlanCursor]
+                    : null;
+                return true;
             }
             entry = default;
             return false;
@@ -209,6 +217,14 @@ public static partial class AcBinarySerializer
         // These properties delegate to Options for convenience
         internal bool UseStringInterning => Options.UseStringInterning != StringInterningMode.None;
 
+        /// <summary>
+        /// Pre-computed <c>1 &lt;&lt; (int)Options.UseStringInterning</c>.
+        /// Used by sgen scan (per-object intern check) and sgen write (per-property StringInternEligible).
+        /// Avoids repeated field chain traversal (context.Options.UseStringInterning) + shift per call site.
+        /// Value: None=1, Attribute=2, All=4.
+        /// </summary>
+        public int InternBit { get; private set; }
+
         public bool IsValidForInterningString(int strLength)
         {
             return strLength >= MinStringInternLength && (MaxStringInternLength == 0 || strLength <= MaxStringInternLength);
@@ -265,6 +281,7 @@ public static partial class AcBinarySerializer
             // IMPORTANT: base.Reset sets Options first, so derived code can use Options-derived properties
             base.Reset(options);
             HasPropertyFilter = Options.PropertyFilter != null;
+            InternBit = 1 << (int)Options.UseStringInterning;
             //FastWire = Options.WireMode == WireMode.Fast;
         }
 
@@ -283,6 +300,7 @@ public static partial class AcBinarySerializer
             ScanVisitIndex = 0;
             WritePlanCursor = 0;
             WriteVisitIndex = 0;
+            _nextWritePlanEntry = null;
             StringInternEligible = false;
 
             // Clear write plan string references to avoid GC pinning, keep array if small enough
diff --git a/AyCode.Core/Serializers/Binaries/AcBinarySerializer.ScanPass.cs b/AyCode.Core/Serializers/Binaries/AcBinarySerializer.ScanPass.cs
index a50d98a..4f34741 100644
--- a/AyCode.Core/Serializers/Binaries/AcBinarySerializer.ScanPass.cs
+++ b/AyCode.Core/Serializers/Binaries/AcBinarySerializer.ScanPass.cs
@@ -173,7 +173,7 @@ public static partial class AcBinarySerializer
 
             if (prop.AccessorType == PropertyAccessorType.String)
             {
-                if (!prop.UseStringPropertyInterning(context.Options.UseStringInterning)) continue;
+                if (!prop.UseStringPropertyInterning(context.InternBit)) continue;
 
                 var str2 = prop.GetString(value);
                 if (str2 != null && context.IsValidForInterningString(str2.Length))
@@ -181,7 +181,7 @@ public static partial class AcBinarySerializer
             }
             else if (prop.IsStringCollectionProperty)
             {
-                if (!prop.UseStringPropertyInterning(context.Options.UseStringInterning)) continue;
+                if (!prop.UseStringPropertyInterning(context.InternBit)) continue;
 
                 var propValue = prop.GetValue(value);
                 if (propValue != null)
diff --git a/AyCode.Core/Serializers/Binaries/AcBinarySerializer.cs b/AyCode.Core/Serializers/Binaries/AcBinarySerializer.cs
index 938b710..d6ab191 100644
--- a/AyCode.Core/Serializers/Binaries/AcBinarySerializer.cs
+++ b/AyCode.Core/Serializers/Binaries/AcBinarySerializer.cs
@@ -1453,7 +1453,7 @@ public static partial class AcBinarySerializer
                     }
                     else
                     {
-                        context.StringInternEligible = prop.UseStringPropertyInterning(context.Options.UseStringInterning);
+                        context.StringInternEligible = prop.UseStringPropertyInterning(context.InternBit);
                         WriteString(value, context);
                     }
                     return;
@@ -1463,7 +1463,7 @@ public static partial class AcBinarySerializer
                     // Object type (collection, complex object, byte[], dictionary)
                     // Use pre-cached wrapper, fallback to GetWrapper on miss/polymorphism
                     // Set interning eligibility for string collection elements
-                    context.StringInternEligible = prop.IsStringCollectionProperty && prop.UseStringPropertyInterning(context.Options.UseStringInterning);
+                    context.StringInternEligible = prop.IsStringCollectionProperty && prop.UseStringPropertyInterning(context.InternBit);
                     var value = prop.GetValue(obj);
 
                     // SKIP marker only for null (reference types)
diff --git a/AyCode.Core/Serializers/Binaries/BinaryPropertyAccessorBase.cs b/AyCode.Core/Serializers/Binaries/BinaryPropertyAccessorBase.cs
index a25bfd9..ac453e7 100644
--- a/AyCode.Core/Serializers/Binaries/BinaryPropertyAccessorBase.cs
+++ b/AyCode.Core/Serializers/Binaries/BinaryPropertyAccessorBase.cs
@@ -43,9 +43,9 @@ public abstract class BinaryPropertyAccessorBase : PropertyAccessorBase
     private readonly byte _interningFlags;
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public bool UseStringPropertyInterning(StringInterningMode stringInterningMode)
+    public bool UseStringPropertyInterning(int internBit)
     {
-        return (_interningFlags & (1 << (int)stringInterningMode)) != 0;
+        return (_interningFlags & internBit) != 0;
     }
     /// <summary>
     /// Object getter for property filter context.