I've been researching event hubs and I'm trying to find a good way to auto scale out my event consumer worker roles. So far, I've only found documentation that suggests using CPU usage as a metric to auto scale, but that obviously won't work if my worker roles are I/O bound. What I really want is some way to measure the number of unprocessed messages for a consumer group which would indicate that I'm falling behind in processing incoming messages for that group, but I haven't found a way to measure this. Is there some way to do this? Or am I going about this the wrong way?
Thanks in advance for any suggestions you may have.
