In a project I am working on, the .3dm model takes around 20 minutes to load into memory and Rhino3D becomes unresponsive during the time. Once loaded, the model runs fairly alright. Hangs up while hiding/unhiding layers, etc. I ran Intel’s VTune Amplifier on Rhino and it naturally showed a single core on my computer being maxed out for over 93% of the process while using OpenNurbs.dll.
Is there a way to recompile the OpenNurbs.dll to make use of idle cores while reading nurbs data from the hard drive?
Just curious, how big is the file you are reading in to Rhino? Does the file contain render meshes, or does Rhino need to generate the meshes upon loading the file? Are you loading the file across a network from a shared drive?
To answer your question, no, there no way to recompile openNURBS to make use of idle cores while reading data from 3dm files.
In general, parallel threads can get your more CPU cycles if you have enough cores. But you still have only one hard disk. So inevitably threads cannot improve the speed of reading file data.