一个数据采集脚本，使用MySQLdb将数据保存到MySQL中，脚本运行一次需要好几天的时间，运行中途出现_mysql_exceptions.OperationalError: (2006, 'MySQL server has gone away') 异常。

因为需要频繁写入数据，每次写入前再建立连接效率太低。但是如果只在开始建立一次连接，就会容易出现MySQL server has gone away的问题。

我使用的方法是给涉及数据库操作的函数加一个装饰器，装饰器函数内部如果捕获到'MySQL server has gone away'异常就尝试重连数据库，装饰器代码如下：

class DB:
    """Database interface"""
    
    def retry(func):
        def call(self, *args, **kwargs):
            #print self.settings
            attempts = 0
            while attempts < 5:
                lock.acquire()
                try:
                    return func(self, *args, **kwargs)
                except MySQLdb.Error, e:
                    common.logger.info(str(e))
                    if 'MySQL server has gone away' in str(e):
                        common.logger.info('MySQL server has gone away, will try to re-connect.')
                        # re-connect MySQL
                        self.connect_mysql()
                        attempts += 1
                    else:
                        # No need to retry for other reasons
                        attempts = 5
                finally:
                    lock.release()
        return call
    
    def __init__(self):
        pass

    @retry
    def save_location(self, location):
        pass