Choppy screen updates

[mikeporter]

OK, this is a "hail mary" pass so to speak.

I have a VI that is displaying 20-30 values that it is reading from shared-variable tags. The reads seem to be going well as the time required to read all the data and stuff it into FP indicators is very consistent. The problem is that while I am reading the all the values every 100msec, the front-panel appears to only update about once per second.

Even stranger, this is only happening on one PC (the customer's, of course) that has multiple monitors attached. Any ideas (wild or otherwise) would be appreciated. 

Oh yes, the code is written in LV2016.

Thanks for an insight you might be able to provide,

Mike...

[MichaelBalzer]

A few questions which come to mind:

• Does setting the Defer Panel Updates property change anything?
• On the multi-monitor setup, does the FP update rate change when the app is moved between the screens? What about if the multi-monitor display is set to a single monitor in Windows?
• If the SV reads are removed and replaced with random values, does the FP update rate change?
• Are the SVs being read in the UI thread?
• Where are the SVs hosted?
• Do any other apps, LabVIEW or otherwise, exhibit this behaviour on the customer PC?

[Ben]

Since it only happening on the customer's PC, it sure sounds like something unique to that PC.

Anti-virus?

Display drivers and acceleration?

What else is using CPU?

Are indictors bound to the SVs?

Poking at the LV code should not be the fix but it could help point out the problem. Defer.FP.Updat (as mentioned previously) may or may not help.

 If the GUI is resizing smaller on the customer's machine, do you have overlapping indicators?

Ben

[mikeporter]

Can you control what thread the SVs are being read in? I am using the tag reader API.

Mike...

[Ben]

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@mikeporter wrote:

Can you control what thread the SVs are being read in? I am using the tag reader API.

Mike...

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Not sure what that is since I seldom use SVs and if I do, I often use Datasocket reads since I can access them programaticaly using the same URL that is used if you sent the binding of the control on the FP.

Using datasockets would let you control what thread is being used by setting the VI doing the datasocket reads to the thread you want.

Ben