fix: [internal] PHP memory leak

app/Lib/Tools/BetterCakeEventManager.php

@@ -0,0 +1,33 @@
+<?php
+class BetterCakeEventManager extends CakeEventManager
+{
+    /**
+     * This method is similar as original dispatch, but do not return newly created event. With returning event, there is
+     * big memory leak in PHP at least for PHP version 7.4.19.
+     * @param CakeEvent $event
+     */
+    public function dispatch($event)
+    {
+        $listeners = $this->listeners($event->name());
+        if (empty($listeners)) {
+            return null;
+        }
+
+        foreach ($listeners as $listener) {
+            if ($event->isStopped()) {
+                break;
+            }
+            if ($listener['passParams'] === true) {
+                $result = call_user_func_array($listener['callable'], $event->data);
+            } else {
+                $result = $listener['callable']($event);
+            }
+            if ($result === false) {
+                $event->stopPropagation();
+            }
+            if ($result !== null) {
+                $event->result = $result;
+            }
+        }
+    }
+}

app/Model/AppModel.php

@@ -25,6 +25,7 @@ App::uses('LogableBehavior', 'Assets.models/behaviors');
 App::uses('RandomTool', 'Tools');
 App::uses('FileAccessTool', 'Tools');
 App::uses('JsonTool', 'Tools');
+App::uses('BetterCakeEventManager', 'Tools');
 
 class AppModel extends Model
 {
@@ -3311,4 +3312,19 @@ class AppModel extends Model
         $dataSourceName = $dataSource->config['datasource'];
         return $dataSourceName === 'Database/Mysql' || $dataSourceName === 'Database/MysqlObserver' || $dataSourceName === 'Database/MysqlExtended' || $dataSource instanceof Mysql;
     }
+
+    /**
+     * Use different CakeEventManager to fix memory leak
+     * @return CakeEventManager
+     */
+    public function getEventManager()
+    {
+        if (empty($this->_eventManager)) {
+            $this->_eventManager = new BetterCakeEventManager();
+            $this->_eventManager->attach($this->Behaviors);
+            $this->_eventManager->attach($this);
+        }
+
+        return $this->_eventManager;
+    }
 }