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Need Advice about PPL Usage

YIKES!

 

A timing study of a simple freestanding VI that performs (C[dbl]=A[dbl}+B[dbl]), shows it takes 53 +/- 1 nSec on my computer.

 

If the VI is in a LVLIB, it changes nothing. Not surprising, as a LVLIB is merely a container for references.

 

However,  the same VI when put into a PPL (*.lvlibp) takes 6850 nSec, or over 120 times the time !

 

That means there is 6.8 uSec of overhead in calling the thing, merely because it's in a PPL.

 

What the heck is going on here?

 

I see in the help that there is an option to have the "Callers adapt at run-time to connector pane state".  

That implies some sort of checking, but dang, does that happen on each and every call?

 

Turning OFF that option seems to make only a slight difference.

 

 

Steve Bird
Culverson Software - Elegant software that is a pleasure to use.
Culverson.com


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Blog for (mostly LabVIEW) programmers: Tips And Tricks

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Well, never mind.  I must have screwed up something in that test - I cannot reproduce those results.

 

Now I get 53 +/- 1 nSec regardless of whether the VI is in a PPL or not.

Steve Bird
Culverson Software - Elegant software that is a pleasure to use.
Culverson.com


LinkedIn

Blog for (mostly LabVIEW) programmers: Tips And Tricks

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Message 22 of 22
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