You won’t find too much explanation about that field in the official documentation but I believe I know what it means.
The blocked process report is closely tied to deadlock detection and it’s generated by the same process as the deadlock monitor. If you remember, the deadlock monitor runs frequently looking for deadlocks (which are just blocking chains in a circle). It runs every couple seconds when there are no deadlocks, and if it detects any, it runs a bit more frequently. Each time it runs it’s called a monitor loop. The
monitorLoopis just a number that starts at zero when the server restarts and increments by one each time the monitor runs.
Read on for more details.