[HTTP Transaction] Perceived Total Time (ms)

The amount of time that it would take a web browser to play the transaction. This is a good metric for setting thresholds because it is the closest active measurement of what the user-experience is likely to be.

User Action

Use this metric to identify problem transactions. After you identify a transaction that's slow to respond to user requests, you can drill down and analyze each phase of the transaction to isolate and repair the problem.