Q:

Out of memory error in loading multiple models in Forge Viewer

I am working on a project that has 14 Navisworks (NWC) models.  I am able to load the composite model into the viewer (which takes some time but works). 
However, when I am loading models one by one into Viewer, I get out of memory error before all 14 are loaded.  Total file size is about 500MB. 
I observed that viewer is very responsive right until browser crashes (while model loading was taking place in the background). 
I suspect this to be an issue of total number of polygons & geometry.  I tied to use NOP_VIEWER.initDebugTools() extension but it doesn't seem to show total count from all models.  It seems to show the details of only first model. 

Is there a way to stop Viewer creating more geometry before it runs out of memory? 
Is there a way to find statistics of all models with DebugTools extension? 
Is there another way to count polygons of loaded models? 

Thanks
Bandu

A:

Is there a way to stop Viewer creating more geometry before it runs out of memory? 

Try and limit the memory consumption in your load options:
var config3d = {
    memory: {
        limit: 1024 // in MB
    }
};
var viewer = new Autodesk. Viewing. Viewer3D(container, config3d);

BTW the default limits are:
Desktop 600 MB
Mobile  195 MB

Is there a way to find statistics of all models with DebugTools extension? 

Unfortunately the built-in DebugTools does not work with multiple models. 
But that shouldn't stop you from querying stats on a per model basis:
let modelArray = viewer.impl.modelQueue().getModels();
let targetModel = modelArray[index];
targetModel.getGeometryList() // retrieves geometry info about a specific model

You can even bake an extension of your own to suit multiple models. 

Is there another way to count polygons of loaded models? 

model.getGeometryList().geomPolyCount

