diff --git a/dynamic-threadpool-spring-boot-starter/src/main/java/io/dynamic/threadpool/starter/toolkit/thread/CustomThreadPoolExecutor.java b/dynamic-threadpool-spring-boot-starter/src/main/java/io/dynamic/threadpool/starter/toolkit/thread/CustomThreadPoolExecutor.java
index 62d3783d..3d195272 100644
--- a/dynamic-threadpool-spring-boot-starter/src/main/java/io/dynamic/threadpool/starter/toolkit/thread/CustomThreadPoolExecutor.java
+++ b/dynamic-threadpool-spring-boot-starter/src/main/java/io/dynamic/threadpool/starter/toolkit/thread/CustomThreadPoolExecutor.java
@@ -717,6 +717,15 @@ public final class CustomThreadPoolExecutor extends ThreadPoolExecutorTemplate {
                 addWorker(null, true);
     }
 
+    void ensurePrestart() {
+        int wc = workerCountOf(ctl.get());
+        if (wc < corePoolSize) {
+            addWorker(null, true);
+        } else if (wc == 0) {
+            addWorker(null, false);
+        }
+    }
+
     @Override
     public int prestartAllCoreThreads() {
         int n = 0;
diff --git a/dynamic-threadpool-spring-boot-starter/src/main/java/io/dynamic/threadpool/starter/toolkit/thread/ResizableCapacityLinkedBlockIngQueue.java b/dynamic-threadpool-spring-boot-starter/src/main/java/io/dynamic/threadpool/starter/toolkit/thread/ResizableCapacityLinkedBlockIngQueue.java
index 8381f555..c8124c20 100644
--- a/dynamic-threadpool-spring-boot-starter/src/main/java/io/dynamic/threadpool/starter/toolkit/thread/ResizableCapacityLinkedBlockIngQueue.java
+++ b/dynamic-threadpool-spring-boot-starter/src/main/java/io/dynamic/threadpool/starter/toolkit/thread/ResizableCapacityLinkedBlockIngQueue.java
@@ -18,7 +18,7 @@ public class ResizableCapacityLinkedBlockIngQueue<E> extends LinkedBlockingQueue
         super(capacity);
     }
 
-    public boolean setCapacity(Integer capacity) {
+    public synchronized boolean setCapacity(Integer capacity) {
         boolean successFlag = true;
         try {
             ReflectUtil.setFieldValue(this, "capacity", capacity);