diff --git a/CHANGELOG.md b/CHANGELOG.md
index af2a0cb26..08f690a63 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,17 @@
 # Changelog
 
+## milvus-sdk-java 2.6.11 (2025-12-26)
+### Improvement
+- Optimize MilvusClientV2Pool/MilvusClientPool to reuse client objects
+- Allow to insert pk even when auto-id is true, milvus v2.6.3 supports
+- Support AddCollectionFunction/AlterCollectionFunction/DropCollectionFunction milvus v2.6.8 supports
+
+### Bug
+- Fix a bug of QueryIterator that query failed when filter expression contains RANDOM_SAMPLE
+- Fix a bug that insert() cannot handle empty struct list
+- Fix a bug that rpcDeadline incorrectly work for iterator
+- Fix a bug that max_lenth of Array/Varchar field missed
+
 ## milvus-sdk-java 2.6.10 (2025-12-01)
 ### Breaking Change
 - Rename "Stage" to "Volume" for BulkWriter
diff --git a/README.md b/README.md
index b5d766ead..4fddc98a0 100644
--- a/README.md
+++ b/README.md
@@ -22,7 +22,7 @@ The following table shows compatibilities between Milvus and Java SDK.
 |     2.3.x      |      2.3.11      |
 |     2.4.x      |      2.4.11      |
 |     2.5.x      |      2.5.15      |
-|     2.6.x      |      2.6.10      |
+|     2.6.x      |      2.6.11      |
 
 ### Install Java SDK
 
@@ -34,20 +34,20 @@ You can use **Apache Maven** or **Gradle** add Milvus SDK to your project.
         <dependency>
             <groupId>io.milvus</groupId>
             <artifactId>milvus-sdk-java</artifactId>
-            <version>2.6.10</version>
+            <version>2.6.11</version>
         </dependency>
        ```
 
    - Gradle/Groovy
 
         ```groovy
-        implementation 'io.milvus:milvus-sdk-java:2.6.10'
+        implementation 'io.milvus:milvus-sdk-java:2.6.11'
         ```
 
    - Gradle/Kotlin
 
         ```kotlin
-        implementation("io.milvus:milvus-sdk-java:2.6.10")
+        implementation("io.milvus:milvus-sdk-java:2.6.11")
         ```
   
 From v2.5.2, milvus Java SDK is split into two packages: milvus-sdk-java and milvus-sdk-java-bulkwriter, because BulkWriter requires quite a lot of dependencies. If you don't need BulkWriter tool, you can ignore the milvus-sdk-java-bulkwriter package.
@@ -59,20 +59,20 @@ To use BulkWriter, import milvus-sdk-java-bulkwriter to your project.
      <dependency>
          <groupId>io.milvus</groupId>
          <artifactId>milvus-sdk-java-bulkwriter</artifactId>
-         <version>2.6.10</version>
+         <version>2.6.11</version>
      </dependency>
     ```
 
    - Gradle/Groovy
 
      ```groovy
-     implementation 'io.milvus:milvus-sdk-java-bulkwriter:2.6.10'
+     implementation 'io.milvus:milvus-sdk-java-bulkwriter:2.6.11'
      ```
 
    - Gradle/Kotlin
 
      ```kotlin
-     implementation("io.milvus:milvus-sdk-java-bulkwriter:2.6.10")
+     implementation("io.milvus:milvus-sdk-java-bulkwriter:2.6.11")
      ```     
 
 ### Examples
diff --git a/docker-compose.yml b/docker-compose.yml
index de96bc933..37361e309 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -3,7 +3,7 @@ version: '3.5'
 services:
   standalone:
     container_name: milvus-javasdk-standalone-1
-    image: milvusdb/milvus:v2.6.6
+    image: milvusdb/milvus:v2.6.7
     command: [ "milvus", "run", "standalone" ]
     environment:
       - COMMON_STORAGETYPE=local
@@ -24,7 +24,7 @@ services:
 
   standaloneslave:
     container_name: milvus-javasdk-standalone-2
-    image: milvusdb/milvus:v2.6.6
+    image: milvusdb/milvus:v2.6.7
     command: [ "milvus", "run", "standalone" ]
     environment:
       - COMMON_STORAGETYPE=local
diff --git a/examples/pom.xml b/examples/pom.xml
index fc8ab8bac..38ea79800 100644
--- a/examples/pom.xml
+++ b/examples/pom.xml
@@ -42,7 +42,7 @@
     </build>
 
     <properties>
-        <revision>2.6.10</revision>
+        <revision>2.6.11</revision>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
 
diff --git a/pom.xml b/pom.xml
index 740549743..5bdf7b485 100644
--- a/pom.xml
+++ b/pom.xml
@@ -82,7 +82,7 @@
     </repositories>
 
     <properties>
-        <revision>2.6.10</revision>
+        <revision>2.6.11</revision>
         <maven.compiler.source>8</maven.compiler.source>
         <maven.compiler.target>8</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
diff --git a/sdk-core/src/main/milvus-proto b/sdk-core/src/main/milvus-proto
index 874a110cd..5b5ad7223 160000
--- a/sdk-core/src/main/milvus-proto
+++ b/sdk-core/src/main/milvus-proto
@@ -1 +1 @@
-Subproject commit 874a110cdf037515529944485534b5db43add044
+Subproject commit 5b5ad7223d65baa6eb3a4bd075969027b10cadf8
diff --git a/sdk-core/src/test/java/io/milvus/TestUtils.java b/sdk-core/src/test/java/io/milvus/TestUtils.java
index 69fd4c9c7..5e7344022 100644
--- a/sdk-core/src/test/java/io/milvus/TestUtils.java
+++ b/sdk-core/src/test/java/io/milvus/TestUtils.java
@@ -11,7 +11,7 @@ public class TestUtils {
     private int dimension = 256;
     private static final Random RANDOM = new Random();
 
-    public static final String MilvusDockerImageID = "milvusdb/milvus:v2.6.6";
+    public static final String MilvusDockerImageID = "milvusdb/milvus:v2.6.7";
 
     public TestUtils(int dimension) {
         this.dimension = dimension;
diff --git a/sdk-core/src/test/java/io/milvus/client/MilvusClientDockerTest.java b/sdk-core/src/test/java/io/milvus/client/MilvusClientDockerTest.java
index ef974a794..748eaeb36 100644
--- a/sdk-core/src/test/java/io/milvus/client/MilvusClientDockerTest.java
+++ b/sdk-core/src/test/java/io/milvus/client/MilvusClientDockerTest.java
@@ -3154,7 +3154,7 @@ void testClientPool() {
 
             List<Thread> threadList = new ArrayList<>();
             int threadCount = 20;
-            int requestPerThread = 1000;
+            int requestPerThread = 10000;
             for (int k = 0; k < threadCount; k++) {
                 Thread t = new Thread(() -> {
                     for (int i = 0; i < requestPerThread; i++) {