Re: [foxboro] CP Loading

  • From: David Johnson <DRJohn@xxxxxxxxxx>
  • To: foxboro@xxxxxxxxxxxxx
  • Date: Thu, 06 Jan 2005 17:20:04 -0600

Foxboro recommends no more than one block per CP. Although this can get a 
little pricey, it keeps the "D" in DCS.

No really, I think there are some CP sizing spreadsheets on the customer 
support web site.

It's easy enough to look at the "LTRBUG"_STA:STATION information either 
with select or using omget to periodically grab a snapshot. Some of the key 
indicators are

"LTRBUG"_STA:STATION.IOLOAD     % of time scanning the physical I/O subsystem
"LTRBUG"_STA:STATION.BPLOAD     % of time processing blocks
"LTRBUG"_STA:STATION.SQLOAD     % of time processing sequence code
"LTRBUG"_STA:STATION.CPLOAD     Total of above

You probably want to keep the CPLOAD < 80% although anything < 90 seems to 
work pretty well on CP40s and CP60s, YMMV.

The object manager also places a load on the CP
"LTRBUG"_STA:STATION.OML_DAV    obeject manager load

"LTRBUG"_STA:STATION.IDLE_TM    % of time doing nothing (kind of)

Make sure that there aren't too many overruns.
"LTRBUG"_STA:STATION.CUMOVR     Total of number of CP overruns since last reset

Look to make sure that everything is phased well and you don't have periods 
and phases that fall together occasionally making for a big spike in CP 

I think that would do it.


"The only reason for time, is so that everything doesn't happen at once." 
Buckaroo Banzai 

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