Specifies the reporting interval in seconds. The default is every 60 seconds. The minimum is every 2 seconds. You can usually get useful results by running the monitor at the default interval during a query or time of day with performance problems. Short intervals may not give meaningful results. Intervals should be proportional to the job time; one minute is generally more than enough.
monitor_options -interval
The first display shows counters from the start of the server. Subsequent displays show the difference from the previous display.