System = 1 indicates to specifically clear the system level counters
System = 1 to separately enable only system level counters (other parameters ignored)
Note that if System level counters are enabled separately, then they must also be specifically stopped or cleared separately (use System = 1 for the Stop() and Clear() methods)
Processes = the number of individual processes to collect counts for
Routines = the number of individual routines to collect counts for
Globals = the number of individual globals to collect counts for
Network = the number of individual network nodes to collect counts for
ProcessList = a $List of specific process IDs to collect counts for
Note that the MONITOR will allocate 'slots' for the number of processes, globals, routines and nodes you indicate. The first 'n' processes, routines, globals and nodes to increment the counters will take those slots, and all counts from other processes, globals, routines, and nodes will be added to the 'Other' slot.
These counters are the same metrics as reported by the PERFMON utility. If you plan to view the data collected via ^PERFMON, you should ensure that the start time for calculating per/second data is properly set for ^PERFMON by running the $$Clear^PERFMON() function. This will reset the counters and start time.
System = 1 indicates to specifically stop the system level counters (if those were started separately)
Returns '0' if not active, or a positive integer if active.
A '1' indicates that PERFMON (or the SystemCounters in this class) are active.
A '2' indicates that %SYS.MONLBL (or the %Monitor.System.LineByLine class) is active.
If the 'System' parameter is included as '1', then this will also return a second comma-delimited piece indicating the status of the 'system-only' level counters documented above in the StartSystemCounters() method. So, a '1,1' means both PERFMON and the system-only counters are active, but have been started separately. A '1,0' means that just a PERFMON collection was started (which includes system-level counters, but they will be stopped when PERFMON is stopped).