I’ve written a trigger to pull information out of web traffic to my web farm. In particular it pulls apart each of the applications in the farm (by unique URI) and run individual metrics on them. I’m able, for instance, to split up the HTTP.thinktime for each sub-URI. For Example http://farm/Site1; http://farm/Site2; http:/farm/site3 etc.
It’s easy enough to push HTTP.thinktime or roundtrip time back up in to an app and then commit. One thing I’m interested in, however, I just can’t figure out how to approach. We’d like to know how many users are active in the system in any given time frame. I can pull the UserIDs for each HTTP session out of a cookie in the HTTP_Request but I’ve no idea how to count unique values.
I’m sure it’s some combination of how I gather the info in the trigger and pass it to the app and how I design the dashboard but I can’t even figure out where to start.