100% CPU usage after launching server

[nayanw775]

Hi PlusToolkit Team,

We are using PlusApp and slicer for the navigation purpose, we have successfully created a server using OpenIGTLinkIF and PlusApp. So issue I am facing is my system gets very slow after connecting OpenIGTLinkIF and PlusApp and this exactly happens when I press Active button on the OpenIGTLink module after creating the connector.
So before launching the server I have noticed CPU usage is somewhere between 5-10% before pressing the Active button and as soon as I make connection active and Start tracking it goes to100%.
Previously we were using PC with i3 2GB graphic card, and 8GB RAM so we thought PC configuration may be making this lapse then we changed it to:

PC configuration - OS -Windows 10, RAM -16GB, Graphic Card-6GB Nvidia, Core i7 9th Generation.

I suppose PC configuration is fine, may be I need to change some settings in the PlusApp or IGTLinkIF, I don’t know exactly where the problem lies.
What should I change in the code to reduce my CPU usage and to minimize the lapse or should I try changing my PC settings from somewhere.
PlusApp Version:2.8.0
Slicer Version: 4.11

Config.txt

[adamrankin]

Are all your cores at 100%?

[nayanw775]

Yes my all cores are at 100% usage

[Sunderlandkyl]

If you set EnableCapturingOnStart to "FALSE" in the capture device, does it reduce the CPU usage?

[nayanw775]

Thanks for the quick response I have to check that, I will set it to false and will get back to you.

[adamrankin]

I do see that enable compression is on, but it seems excessive that a single tracker device would use 100%. Depends if’s all cores or a single core. Adam

…

On Feb 20, 2021, at 11:20, Kyle Sunderland ***@***.***> wrote:  If you set EnableCapturingOnStart to "FALSE" in the capture device, does it reduce the CPU usage? — You are receiving this because you commented. Reply to this email directly, view it on GitHub, or unsubscribe.

[nayanw775]

Machine have total of 6cores and all are at 100% usage

[nayanw775]

Hi @adamrankin and @Sunderlandkyl

Sorry for writing so late, I went ahead with the changes that you suggested, CPU usage has reduced just a bit, I do not what configurations others are using, because I have read people using the dual core CPU also for the same process and still manage to run smoothly.

Would you like to suggest any other changes.

Thanks,
Nayan

[nayanw775]

So would you suggest changes that you have mentioned in this thread
https://discourse.slicer.org/t/high-slicer-cpu-usage-while-live-streaming/6078

[nayanw775]

So here are the screenshots of the CPU usage before and after launching the Server

[adamrankin]

I've replicated your setup and I am not experiencing the increase. I am continuing to investigate.

[nayanw775]

Hi @adamrankin thanks for the update one more thing I would like to confirm, while testing are you using Volume rendering or models for the registration(if only you are doing)

[adamrankin]

No, I'm only streaming data from Plus to Slicer. In your screenshots, is it PlusServer.exe that is at 100%, or SlicerApp-Real.exe?

[nayanw775]

It is SlicerApp-Real.exe is 100%
But it only turns to 100% once I launch the server

[adamrankin]

Ah, this isn't a bug in Plus. I suspect your volume rendering is set to CPU render. Check the volume rendering panel for CPU/GPU options.

[adamrankin]

#790 (reply in thread)

Not a bug, CPU usage is from Slicer.

[lassoan]

You can reduce CPU usage in Slicer by switching to GPU volume rendering.