I think the check for the namespace is nice but unnecessary. The redis-client *should* automatically prepend it to the beginning of all keys you try to fetch (verify this, and if so there are a number of references to clean up below). Also, I think the `Array(...)` calls are superflous. This should be sufficient:

```ruby
timestamps = Resque.redis.zrange('delayed_queue_schedule', 0, -1)
```

This will always return an array, it just may be empty.

In theory, this should be totally safe:

```ruby
Resque.redis.zrange('delayed_queue_schedule', 0, -1).map do |timestamp|
   ...
end