diff --git a/pom.xml b/pom.xml
index 669496d..8cba8cd 100644
--- a/pom.xml
+++ b/pom.xml
@@ -3,7 +3,7 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>io.github.yezhihao</groupId>
     <artifactId>protostar</artifactId>
-    <version>2.0.3.RELEASE</version>
+    <version>2.0.4.RELEASE</version>
     <packaging>jar</packaging>
 
     <name>Protostar</name>
@@ -62,7 +62,7 @@
         <dependency>
             <groupId>io.netty</groupId>
             <artifactId>netty-buffer</artifactId>
-            <version>4.1.66.Final</version>
+            <version>4.1.68.Final</version>
             <scope>provided</scope>
         </dependency>
     </dependencies>
diff --git a/src/main/java/io/github/yezhihao/protostar/FieldFactory.java b/src/main/java/io/github/yezhihao/protostar/FieldFactory.java
index 794a0e8..c9a8511 100644
--- a/src/main/java/io/github/yezhihao/protostar/FieldFactory.java
+++ b/src/main/java/io/github/yezhihao/protostar/FieldFactory.java
@@ -65,7 +65,7 @@ public abstract class FieldFactory {
                     fieldSchema = ConvertSchema.getInstance(field.converter());
                 break;
             case LIST:
-                fieldSchema = CollectionSchema.getInstance(schema);
+                fieldSchema = CollectionSchema.getInstance(schema, field.lengthSize());
                 break;
             case MAP:
                 fieldSchema = ConvertSchema.getInstance(field.converter());
@@ -85,7 +85,7 @@ public abstract class FieldFactory {
                 result = new FixedField.Logger(field, f, fieldSchema);
             }
         } else {
-            if (field.lengthSize() > 0) {
+            if (field.lengthSize() > 0 && !(fieldSchema instanceof CollectionSchema)) {
                 result = new DynamicLengthField(field, f, fieldSchema);
             } else if (field.length() > 0) {
                 result = new FixedLengthField(field, f, fieldSchema);
diff --git a/src/main/java/io/github/yezhihao/protostar/field/BasicField.java b/src/main/java/io/github/yezhihao/protostar/field/BasicField.java
index 99ae93d..2de58e5 100644
--- a/src/main/java/io/github/yezhihao/protostar/field/BasicField.java
+++ b/src/main/java/io/github/yezhihao/protostar/field/BasicField.java
@@ -3,8 +3,6 @@ package io.github.yezhihao.protostar.field;
 import io.github.yezhihao.protostar.annotation.Field;
 import io.github.yezhihao.protostar.util.StrUtils;
 import io.netty.buffer.ByteBuf;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 /**
  * 固定长度的字段
@@ -12,7 +10,6 @@ import org.slf4j.LoggerFactory;
  * home https://gitee.com/yezhihao/jt808-server
  */
 public abstract class BasicField<T> implements Comparable<BasicField<T>> {
-    protected static Logger log = LoggerFactory.getLogger(BasicField.class.getSimpleName());
 
     protected final int index;
     protected final int length;
diff --git a/src/main/java/io/github/yezhihao/protostar/schema/CollectionSchema.java b/src/main/java/io/github/yezhihao/protostar/schema/CollectionSchema.java
index 8bc54ae..69cc063 100644
--- a/src/main/java/io/github/yezhihao/protostar/schema/CollectionSchema.java
+++ b/src/main/java/io/github/yezhihao/protostar/schema/CollectionSchema.java
@@ -1,6 +1,7 @@
 package io.github.yezhihao.protostar.schema;
 
 import io.github.yezhihao.protostar.Schema;
+import io.github.yezhihao.protostar.util.ByteBufUtils;
 import io.github.yezhihao.protostar.util.Cache;
 import io.netty.buffer.ByteBuf;
 
@@ -9,28 +10,42 @@ import java.util.List;
 
 public class CollectionSchema<T> implements Schema<List<T>> {
 
-    private static final Cache<Schema, CollectionSchema> CACHE = new Cache<>();
+    private static final Cache<String, CollectionSchema> CACHE = new Cache<>();
 
-    public static CollectionSchema getInstance(Schema schema) {
-        return CACHE.get(schema, key -> new CollectionSchema(key));
+    public static CollectionSchema getInstance(Schema schema, int lengthSize) {
+        return CACHE.get(schema.hashCode() + "_" + lengthSize, key -> new CollectionSchema(schema, lengthSize));
     }
 
     private final Schema<T> schema;
 
-    private CollectionSchema(Schema<T> schema) {
+    private final int lengthSize;
+
+    private CollectionSchema(Schema<T> schema, int lengthSize) {
         this.schema = schema;
+        this.lengthSize = lengthSize;
     }
 
     @Override
     public List<T> readFrom(ByteBuf input) {
         if (!input.isReadable())
             return null;
-        List<T> list = new ArrayList<>();
-        do {
-            T obj = schema.readFrom(input);
-            if (obj == null) break;
-            list.add(obj);
-        } while (input.isReadable());
+        List<T> list;
+        if (lengthSize > 0) {
+            int length = ByteBufUtils.readInt(input, lengthSize);
+            list = new ArrayList<>(length);
+            for (int i = 0; i < length; i++) {
+                T obj = schema.readFrom(input);
+                if (obj == null) break;
+                list.add(obj);
+            }
+        } else {
+            list = new ArrayList<>(2);
+            do {
+                T obj = schema.readFrom(input);
+                if (obj == null) break;
+                list.add(obj);
+            } while (input.isReadable());
+        }
         return list;
     }
 
@@ -48,7 +63,8 @@ public class CollectionSchema<T> implements Schema<List<T>> {
     public void writeTo(ByteBuf output, List<T> list) {
         if (list == null || list.isEmpty())
             return;
-
+        if (lengthSize > 0)
+            ByteBufUtils.writeInt(output, lengthSize, list.size());
         for (T obj : list) {
             schema.writeTo(output, obj);
         }