%PerfCounter, %PerfCounterR functions

Function
The function returns the value of the given "Performance Counter".


Declaration
INT %PerfCounter(
   TEXT in text
 )
 


REAL %PerfCounterR(
   TEXT in text
 )
Parameters
textPerformance Counter definition.
Description
Performance Counter definition syntax is as follows:

\\ComputerName\Object(instance)\Counter.

If you want to monitor the counter on a local computer, the first part giving the computer name may be omitted. If an object has only one instance, the part "instance" is omitted.
If the function %PerfCounter (%PerfCounterR) is called frequently (more times than once per second), it returns the wrong values (0).
If there is the need to call the function each second for more system information, we recommend executing each function call on the different line in the ESL script.

Example
%PerfCounter("\D2000 Server\MemUsed")    ; returns the memory size used by process D2000 Server
Note 1
In some situations (for specific counters), the %PerfCounter returns always zero at first calling, e.g. for load counter of processor: " \Processor(_Total)\% User Time". Then you must call this function twice in a loop with delay (the delay must be set empirically) between the callings.
For other counters (e.g. "\Memory\Available MBytes", "\LogicalDisk(C:)\% Free Space" or "\Process(_Total)\Handle count"), this function works without any problems and returns the correct value immediately at first call.
Apparently, there is a problem with the counters that requires a certain time between the registration of the counter and reading its value.

This is an example of the code which calls %PerfCounter twice with the delay of 0.1 seconds if the value 0 has been read during the first call:


 INT _i
 REAL _result
 
 FOR _i=1 TO 2 DO_LOOP
  _result := %PerfCounter("\Processor(_Total)\% User Time")
  IF _result\VLD THEN
   IF _result=0 & _i=1 THEN       ; workaround - at first calling (e.g. it returns 0 on \Processor (_Total)\% User Time)
    DELAY 0.1 [s]
   ELSE
    EXIT_LOOP
   ENDIF
  ELSE
   EXIT_LOOP
  ENDIF
 END_LOOP
 


This code does not work because the same row is not called twice, the same instance of PerfCounter function:


 


 INT _i
 REAL _result
 
 _result := %PerfCounter(_counter)
 IF _result\VLD THEN
  IF _result=0 THEN   ; NONFUNCTIONAL workaround - at first calling (e.g. it returns 0 on \Processor(_Total)\% User Time)
   DELAY 0.05 [s]
   _result := %PerfCounter(_counter)
  ENDIF
 ENDIF
Note 2
We recommend using the %PerfCounterR when it is assumed that the value will be higher than 2 147 483 647.


Related pages:

Implemented functions
Function arguments - types

Napíšte komentár