Opening a second instance of Photoscan seems to kill GPU processing on first?

[MeHoo]

I am using the Nvidia GPU utilization tool.  My main display is running off of my Quadro K4000 since it's the weaker card for openCL calculations compared to my other two GTX 970s in the same system.

When building dense cloud, it shows no utilization on the GTX cards at all.  Is there some sort of conflict going on here, or should I be using another tool to monitor that works better (is it the monitor or photoscan?)?

I have seen reports in the log after some scans that the GPUs are working, as they show the 970's being twice as fast as the Quadro, but right now, it appears that they are doing nothing.

Also.. if I run other software that is highly GPU dependent, such as Knald, and dedicate it to my Quadro, would Photoscan have a struggle between the other software, or would they both just run slower?  I ask because I am getting program crashes with Knald, and I am waiting on this scan to finish to run more tests with the Quadro left out of the scans, etc.

Any info from anyone with any experience with something similar, please let me know.  This whole area seems sort of mystical to me. ;p

[Alexey Pasumansky]

Hello MeHoo,

Have you checked on both GPUs in the OpenCL tab of PhotoScan Preferences window?

[MeHoo]

Yessir...

After running a few more scans to test, it seems that only part of the dense point cloud generation step uses the gpus?

This dense point cloud generation was going strong on all three gpus, but now... Screenshot attached. 

[Alexey Pasumansky]

Hello MeHoo,

At the moment PhotoScan uses GPU only for the depth maps estimation (first step of the Build Dense Cloud stage).