He he. You are talking to a bunch of engineers. What did you expect? :)
Your comments about fastest_rsr are interesting. We were discussing this
problem here a little while back, and I perused the FoxAPI docs to try and
get a better understanding (I've never programmed FoxAPI, and don't claim
to be an expert on it). They seemed to imply that applications could set a
scan rate per list when opening lists, and maybe per tag when using other
calls. They mentioned fastest_rsr, but did not make clear how it
interacted with the lists' scan rates. I assumed it was a lower bound from
a scan period standpoint, but lists could scan more slowly (higher periods)
if the applications that opened them passed the right info in the function
calls.
Having said that, we run Aspen IP.21, and setting fastest_rsr from nothing
(defaults to 0.5s) to 20 (10s) increased our CP idle time from 5-10% on
anything below a CP60, and 1-3% on the CP60s. So either fastest_rsr
overrides everything as you said, or IP.21 doesn't specify slower scan
rates on its lists (we scan everything at 10s or slower in IP.21), or both.
Corey Clingo
BASF Corp
|---------+---------------------------->
| | "Johnson, Alex |
| | (Foxboro)" |
| | <ajohnson@Foxboro|
| | .com> |
| | Sent by: |
| | foxboro-bounce@fr|
| | eelists.org |
| | |
| | |
| | 12/11/2002 09:35 |
| | AM |
| | Please respond to|
| | foxboro |
| | |
|---------+---------------------------->
>-------------------------------------------------------------------------------------------------------------------------------|
|
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| To: foxboro
|
| cc:
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| Subject: Re: [foxboro] FOXAPI Configuration for Foxhistory Ver 2.0
|
>-------------------------------------------------------------------------------------------------------------------------------|
Re: Actually sampling theory, ie. Nyquist, says that you should sample at
least twice as fast as the fastest frequency that is present in the data.
I knew when I wrote that I should have said that this is an approximation
of
the theory. I actually wrote that, but decided that it was distracting.
Sigh...
It is hard to know how much detail to provide sometimes.
Regards,
Alex Johnson
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