关于给用户发送邮件的一些问题
现在要给全部用户或者指定用户发送邮件，“发送”操作是由我们后台人员触发的。
发送操作提交后，我们就要给用户发送了，在发送过程中可能会存在一个问题，就是发送了一段时间后，程序因某些原因死掉了，这样就导致一些用户没有收到邮件，所以我的想法是发送前先把数据库里的用户全写入到一个文件中，发送时从文件中取用户，然后再弄个用户发送日志以记录哪些用户发送了，这样出问题后，可以从出问题的“那个地方”接着执行发送.....
不知道我的想法行不行，另外我担心“把数据库中的用户写入到文件中”这个过程所花费的时间会很长，从而导致性能上会存在隐患。谢谢大家讨论我的想法，给些意见或指点！
回复内容：
现在要给全部用户或者指定用户发送邮件，“发送”操作是由我们后台人员触发的。
发送操作提交后，我们就要给用户发送了，在发送过程中可能会存在一个问题，就是发送了一段时间后，程序因某些原因死掉了，这样就导致一些用户没有收到邮件，所以我的想法是发送前先把数据库里的用户全写入到一个文件中，发送时从文件中取用户，然后再弄个用户发送日志以记录哪些用户发送了，这样出问题后，可以从出问题的“那个地方”接着执行发送.....
不知道我的想法行不行，另外我担心“把数据库中的用户写入到文件中”这个过程所花费的时间会很长，从而导致性能上会存在隐患。谢谢大家讨论我的想法，给些意见或指点！
和@舞林 同学的想法有点相似：
- 把待发的邮件，存储到列表（Lists）中，通过
lpush插入到Redis消息队列中 - 负责发送邮件的代码中通过BRPOP依次消息队列中的内容并进行处理，如果没有新邮件则会阻塞等待直到有新的消息
这样的话不管程序死掉或者什么原因都不会千万消息丢失，同时也可以不用另外加一个定时任务
相比于写文件或者是其它的方法，Redis是目前最合适的
Redis是一个开源、支持网络、基于内存、键值对存储数据库
参考：http://zh.wikipedia.org/zh/Redis
我的做法是邮件队列，放redis，crontab每分钟发送，脚本起来的时候发现上个脚本还在跑就退出，为了避免异常，脚本最多执行110秒。做好失败的监控，没啥问题。
还有什么呢，继续吧...
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