問題描述
使用django+celery時, 運行長時間的任務, 一開始操做一次數據庫, 20個小時後再次操做數據庫.php
過了20多個小時, 再次操做數據庫時報錯.html
raised unexpected: OperationalError(2006, 'MySQL server has gone away') Traceback (most recent call last): File "/usr/local/lib/python2.7/dist-packages/django/db/models/manager.py", line 85, in manager_method return getattr(self.get_queryset(), name)(*args, **kwargs) File "/usr/local/lib/python2.7/dist-packages/django/db/models/query.py", line 374, in get num = len(clone) File "/usr/local/lib/python2.7/dist-packages/django/db/models/query.py", line 232, in __len__ self._fetch_all() File "/usr/local/lib/python2.7/dist-packages/django/db/models/query.py", line 1118, in _fetch_all self._result_cache = list(self._iterable_class(self)) File "/usr/local/lib/python2.7/dist-packages/django/db/models/query.py", line 53, in __iter__ results = compiler.execute_sql(chunked_fetch=self.chunked_fetch) File "/usr/local/lib/python2.7/dist-packages/django/db/models/sql/compiler.py", line 894, in execute_sql raise original_exception OperationalError: (2006, 'MySQL server has gone away')
緣由
鏈接超時
我出現問題就是這個緣由.
進入mysql,執行下面的命令:前端
mysql> show global variables like '%timeout'; +----------------------------+----------+ | Variable_name | Value | +----------------------------+----------+ | connect_timeout | 10 | | delayed_insert_timeout | 300 | | innodb_lock_wait_timeout | 50 | | innodb_rollback_on_timeout | OFF | | interactive_timeout | 28800 | | lock_wait_timeout | 31536000 | | net_read_timeout | 30 | | net_write_timeout | 60 | | slave_net_timeout | 3600 | | wait_timeout | 28800 | +----------------------------+----------+
wait_timeout 是28800秒，即mysql連接在無操做28800秒後被自動關閉python
解決方法
當即生效
執行下面的sql命令mysql
mysql> set global wait_timeout=60*60*30;
- 1
該命令是將wait_timeout設置爲30小時.
用這種方法,修改完當即生效. 若是重啓mysql, 又恢復原來的28800秒.linux
永久生效
該方法修改完以後, 須要重啓mysql才能生效.
編輯mysql配置文件my.cnf,添加或修改成下面這條命令.
(個人mysql配置文件路徑: /etc/mysql/my.cnf )web
wait_timeout = 108000
- 1
其餘緣由
還有一些其餘緣由, 簡單描述一下
1: mysql服務關閉
2: 數據包 過大
解決方法: 修改 max_allowed_packet 的值, 方法同上.sql
