diff --git a/lib/utils/mode/impl/worker_threads/app.js b/lib/utils/mode/impl/worker_threads/app.js
index a55becb..85191a9 100644
--- a/lib/utils/mode/impl/worker_threads/app.js
+++ b/lib/utils/mode/impl/worker_threads/app.js
@@ -156,7 +156,10 @@ class AppUtils extends BaseAppUtils {
     this.startSuccessCount = 0;
 
     const ports = this.options.ports;
-    this.options.workers = ports.length ? ports.length : 1;
+    if (!ports.length) {
+      ports.push(this.options.port);
+    }
+    this.options.workers = ports.length;
     let i = 0;
     do {
       const options = Object.assign({}, this.options, { port: ports[i] });