High CPU usage of Labview executables when using remote desktop

[martien]

Hi all

I have a set of Labview executables which run on some PC's (Labview 2015SP1) and are designed to run continuously. On a few of these PC's, the CPU usage of all executables can suddenly go to high levels when I connect to the PC via remote desktop and subsequently stay at this high level (in this mode the CPU usage is approximately 5 to 10 times as high). I use two different remote desktop programs (RemoteNG and Windows RDP) and this behaviour happens with both of them. The behaviour seems to be relatively random, but it definitely has to do something with the screen resolution. If the CPU has gone to high level and if I then go to the affected PC and log in locally, I can still see the CPU at high level (I use Performance Monitor to log CPU usage of my executables). Changing the resolution of the display to a lower resolution results in an immediate drop of the CPU usage to the normal level for all executables. Then I can set the resolution back to the original level and the CPU usage remains low until I access again the PC via remote desktop. 

The problem is that my executables seem to run less reliable if these run in the high CPU consuming mode. It also happens occasionally that when I remote access a PC where the executables are already running in high CPU mode that one of these program crashes (on a memory failure problem). 

I presume it has to do something with the Labview user interface thread involved with screen updating. I did add a new executable with a different User Interface (a very simple one), to check if it is related somehow to the design of the user interface, but also this program showed the same behaviour.

I have found some old threads discussing this behaviour, but I could not find any solution. Are there some settings possible in my Labview builds which might prevent this problem ?

I have tried with setting the Screen resolution in mRemoteNG to the same one as the resolution of the PC where I want to log in, it sometimes seems to help and prevent this problem. However, next time it is not.

Thanks in advance

Martien

[Kyle97330]

Are these Windows 10 PCs?  The Windows 10 scaling settings and LabVIEW have not gotten along with each other, and it could be the remote desktop is messing it up even further.

Any chance you could try a newer version of LabVIEW just to see if the problem might have been patched out in the last 5 years of updates?

You could try applying some of the settings mentioned in this KB and see if it brings the CPU usage down?

[martien]

Dear Kyle

Yes, these are indeed WIndows 10 PC's. I can understand that the Labview version which I am using (2015) can have compatibility issues. Regretfully, right now an upgrade to a newer Labview version is not yet an option for us (it will be in the near future when we will be getting a later release).

I did see already the article you are referring to. I did not further follow the advices given as none of the issues listed seem to apply to me. In all cases the UI works as expected with every resolution I use through my remote desktop session (I need to mention that I strictly use one predefined font type in all my controls to avoid that the UI looks different and drop downs etc are distorted on some resolutions). The only problem observed is this high increase in CPU usage. 

I do occasionally remote in  from high DPI screens, so I will check if the suggestions on the high DPI scaling in this article will bring some relieve.

Thanks for your reply

Martien