I thought we also were not going to bother with this, for the following reasons:

1. As it stands right now the request id isn't even used, and not worrying about this value will have a performance improvement.
2. This implementation still does not guarantee that a request id will be unique across multiple Ruby processes. In fact in a common situation when using Passenger or Unicorn we are going to have duplicate request ids in very close succession. If we are going to lock here, it's probably better to initialize the request id as a random instead of zero.