diff --git a/module/cron/control.php b/module/cron/control.php
index 5877d5d108..b52506336a 100644
--- a/module/cron/control.php
+++ b/module/cron/control.php
@@ -137,35 +137,29 @@ class cron extends control
     {
         if(empty($this->config->global->cron)) return;
 
-        if('cli' !== PHP_SAPI)
-        {
-            ignore_user_abort(true);
-            set_time_limit(0);
-            session_write_close();
-        }
+        ignore_user_abort(true);
+        set_time_limit(0);
+        session_write_close();
+
+        $execId = mt_rand();
+        if($restart) $this->cron->restartCron($execId);
 
         $this->loadModel('common');
 
-        $execId = mt_rand();
         while(true)
         {
-            dao::$cache = array();
-
-            if($restart) $this->cron->clearQueue();
-
-            if($restart || $this->canSchedule($execId))
+            $roles = $this->applyExecRoles($execId);
+            if(empty($roles))
             {
-                $this->schedule($execId);
-                $this->execTasks($execId);
+                $this->cron->logCron('exit');
+                ignore_user_abort(false);
+                return;
+            }
 
-                $restart = false;
-                sleep(20);
-            }
-            else
-            {
-                $this->execTasks($execId);
-                return;  // If no task in queue, executor will exit.
-            }
+            if(in_array('scheduler', $roles)) $this->schedule($execId);
+            if(in_array('consumer', $roles))  $this->consumeTasks($execId);
+
+            sleep(20);
         }
     }
 
@@ -188,23 +182,17 @@ class cron extends control
         $execId = mt_rand();
         while(true)
         {
-            dao::$cache = array();
-
             if(empty($this->config->global->cron))
             {
                 sleep(60);
                 continue;
             }
 
-            if($restart) $this->cron->clearQueue();
+            if($restart) $this->cron->restartCron($execId);
 
-            if($restart || $this->canSchedule($execId))
-            {
-                $this->schedule($execId);
-                $restart = false;
-            }
+            if($this->canSchedule($execId)) $this->schedule($execId);
 
-            sleep(30);
+            sleep(20);
         }
     }
 
@@ -223,6 +211,7 @@ class cron extends control
 
         $this->loadModel('common');
 
+        $execId = mt_rand();
         while(true)
         {
             if(empty($this->config->global->cron))
@@ -231,8 +220,8 @@ class cron extends control
                 continue;
             }
 
-            $this->execTasks(mt_rand());
-            sleep(10);
+            $this->consumeTasks($execId);
+            sleep(20);
         }
     }
 
@@ -246,13 +235,57 @@ class cron extends control
      */
     protected function canSchedule($execId)
     {
-        $settings = $this->dao->select('`key`,`value`')->from(TABLE_CONFIG)->where('owner')->eq('system')->andWhere('module')->eq('cron')->andWhere('section')->eq('run')->fetchPairs();
+        $settings = $this->dao->select('`key`,`value`')->from(TABLE_CONFIG)->where('owner')->eq('system')->andWhere('module')->eq('cron')->andWhere('section')->eq('scheduler')->fetchPairs();
         if(!isset($settings['execId']) || $settings['execId'] == $execId) return true;
         if(!isset($settings['lastTime']) || $settings['lastTime'] < date('Y-m-d H:i:s', strtotime('-1 minute'))) return true;
 
         return false;
     }
 
+    /**
+     * 检查该execId是否可以执行任务(最多允许1个调度进程，4个执行进程).
+     * Check the execId can exec(1 scheduler, 4 consumer).
+     *
+     * @param  int    $execId
+     * @access protected
+     * @return array
+     */
+    protected function applyExecRoles($execId)
+    {
+        $roles = array();
+
+        $settings = $this->dao->select('*')->from(TABLE_CONFIG)->where('owner')->eq('system')->andWhere('module')->eq('cron')->fetchAll();
+
+        $scheduler = array('execId' => 0, 'lastTime' => '');
+        $consumerCount = 0;
+
+        $expirDate = date('Y-m-d H:i:s', strtotime('-1 minute'));
+        foreach($settings as $setting)
+        {
+            if($setting->section == 'scheduler' && $setting->key == 'lastTime') $scheduler['lastTime'] = $setting->value;
+            if($setting->section == 'scheduler' && $setting->key == 'execId')   $scheduler['execId']   = $setting->value;
+
+            if($setting->section == 'consumer')
+            {
+                if($setting->value > $expirDate)
+                {
+                    if($setting->key == strval($execId)) $roles[] = 'consumer';
+                    $consumerCount ++;
+                }
+                else
+                {
+                    $this->dao->delete()->from(TABLE_CONFIG)->where('id')->eq($setting->id)->exec();
+                }
+            }
+
+        }
+
+        if(in_array($scheduler['execId'], array(0, $execId)) || $scheduler['lastTime'] < $expirDate) $roles[] = 'scheduler';
+        if($consumerCount < 4) $roles[] = 'consumer';
+
+        return $roles;
+    }
+
     /**
      * 调度生成队列任务.
      * Schedule, push tasks to queue.
@@ -263,10 +296,9 @@ class cron extends control
      */
     public function schedule($execId)
     {
-        $now = date(DT_DATETIME1);
+        dao::$cache = array();
 
-        $this->loadModel('setting')->setItem('system.cron.run.execId', $execId);
-        $this->setting->setItem('system.cron.run.lastTime', $now);
+        $this->cron->updateTime('scheduler', $execId);
 
         /* Get and parse crons. */
         $tasks = $this->dao->select('cron,MAX(`createdDate`) `datetime`')->from(TABLE_QUEUE)->groupBy('cron')->fetchAll('cron');
@@ -311,16 +343,19 @@ class cron extends control
      * @access public
      * @return bool
      */
-    public function execTasks($execId)
+    public function consumeTasks($execId)
     {
         while(true)
         {
             dao::$cache = array();
 
+            $this->cron->updateTime('consumer', $execId);
+
+            /* Consume. */
             $task = $this->dao->select('*')->from(TABLE_QUEUE)->where('status')->eq('wait')->andWhere('command')->ne('')->orderBy('createdDate')->fetch();
             if(!$task) break;
 
-            $this->execTask($execId, $task);
+            $this->consumeTask($execId, $task);
         }
     }
 
@@ -333,7 +368,7 @@ class cron extends control
      * @access public
      * @return bool
      */
-    public function execTask($execId, $task)
+    public function consumeTask($execId, $task)
     {
         /* Other executor may execute the task at the same time，so we mark execId and wait 500ms to check whether we own it. */
         $this->dao->update(TABLE_QUEUE)->set('status')->eq('doing')->set('execId')->eq($execId)->where('id')->eq($task->id)->exec();
diff --git a/module/cron/model.php b/module/cron/model.php
index 3a4fe22798..8e4f248003 100644
--- a/module/cron/model.php
+++ b/module/cron/model.php
@@ -312,16 +312,91 @@ class cronModel extends model
     }
 
     /**
-     * Clear queue.
+     * Restart cron.
      *
      * @access public
      * @return void
      */
-    public function clearQueue()
+    public function restartCron($execId)
     {
+        $this->dao->update(TABLE_CONFIG)->set('value')->eq($execId)
+            ->where('owner')->eq('system')
+            ->andWhere('module')->eq('cron')
+            ->andWhere('section')->eq('scheduler')
+            ->andWhere('`key`')->eq($execId)
+            ->exec();
         $this->dao->delete()->from(TABLE_QUEUE)->where('createdDate')->le(date("Y-m-d H:i:s", strtotime("-1 week")))->exec();
 
-        $log = date('G:i:s') . " clear\n\n";
-        $this->logCron($log);
+        $this->logCron(date('G:i:s') . " restart\n\n");
+    }
+
+    /**
+     * Update last time of cron.
+     *
+     * @param string $role
+     * @param int    $execId
+     * @access public
+     * @return void
+     */
+    public function updateTime($role, $execId)
+    {
+        $now = date(DT_DATETIME1);
+
+        $settings = $this->dao->select('*')->from(TABLE_CONFIG)->where('owner')->eq('system')->andWhere('module')->eq('cron')->andWhere('section')->eq($role)->fetchAll('key');
+        if($role == 'scheduler')
+        {
+            if(isset($settings['execId']))
+            {
+                $setting = $settings['execId'];
+                if($setting->value != strval($execId)) $this->dao->update(TABLE_CONFIG)->set('value')->eq($execId)->where('id')->eq($setting->id)->exec();
+            }
+            else
+            {
+                $data = new stdclass();
+                $data->owner   = 'system';
+                $data->module  = 'cron';
+                $data->section = 'scheduler';
+                $data->key     = 'execId';
+                $data->value   = $execId;
+
+                $this->dao->insert(TABLE_CONFIG)->data($data)->exec();
+            }
+
+            if(isset($settings['lastTime']))
+            {
+                $setting = $settings['lastTime'];
+                $this->dao->update(TABLE_CONFIG)->set('value')->eq($now)->where('id')->eq($setting->id)->exec();
+            }
+            else
+            {
+                $data = new stdclass();
+                $data->owner   = 'system';
+                $data->module  = 'cron';
+                $data->section = 'scheduler';
+                $data->key     = 'lastTime';
+                $data->value   = $now;
+
+                $this->dao->insert(TABLE_CONFIG)->data($data)->exec();
+            }
+        }
+        else
+        {
+            if(isset($settings[strval($execId)]))
+            {
+                $setting = $settings[strval($execId)];
+                $this->dao->update(TABLE_CONFIG)->set('value')->eq($now)->where('id')->eq($setting->id)->exec();
+            }
+            else
+            {
+                $data = new stdclass();
+                $data->owner   = 'system';
+                $data->module  = 'cron';
+                $data->section = 'consumer';
+                $data->key     = $execId;
+                $data->value   = $now;
+
+                $this->dao->insert(TABLE_CONFIG)->data($data)->exec();
+            }
+        }
     }
 }