为了在redis中实现一个简单的队列，该队列可用于重新提交崩溃的作业，我会尝试如下操作：

• 1个清单“ up_for_grabs”
• 1个清单“ being_worked_on”
• 自动过期锁

试图找工作的工人会做这样的事情：

timeout = 3600
#wrap this in a transaction so our cleanup wont kill the task
#Move the job away from the queue so nobody else tries to claim it
job = RPOPLPUSH(up_for_grabs, being_worked_on)
#Set a lock and expire it, the value tells us when that job will time out. This can be arbitrary though
SETEX('lock:' + job, Time.now + timeout, timeout)
#our application logic
do_work(job)

#Remove the finished item from the queue.
LREM being_worked_on -1 job
#Delete the item's lock. If it crashes here, the expire will take care of it
DEL('lock:' + job)

而且不时地，我们只需获取清单并检查其中的所有作业实际上是否都已锁定。如果我们发现没有锁的任何作业，则意味着该作业已过期，我们的工作人员很可能崩溃了。在这种情况下，我们将重新提交。

这将是伪代码：

loop do
    items = LRANGE(being_worked_on, 0, -1)
    items.each do |job| 
        if !(EXISTS("lock:" + job))
            puts "We found a job that didn't have a lock, resubmitting"
            LREM being_worked_on -1 job
            LPUSH(up_for_grabs, job)
        end
    end
    sleep 60
end