Elasticsearch scroll常见错误

最近使用es嘎嘎报错：

Trying to create too many scroll contexts. Must be less than or equal to: [500]

• 原因：在search()中设置的timeout时间内，累计生成的scroll_id数超过了最大限制
• 解决方法：查询scroll以后，删除对应的id，即调用clearScroll方法
  

          //搜索查询
          $response = $this->client->search($params);
          while (isset($response['hits']['hits']) && count($response['hits']['hits']) > 0) {
   
              //对response内容进行处理
              $scroll_id = $response['_scroll_id'];
              // Execute a Scroll request and repeat
              $response = $this->client->scroll([
                   'scroll_id' => $scroll_id,      //游标id
                   'scroll'    => $timeout         //超时时间
              ]);
   
          }
          //清除scroll_id
          $this->client->clearScroll(array('scroll_id' => $response['_scroll_id']));