How can I increase the resources ArcMap uses?

[BenPampel]

I have a lot of free memory and CPU that ArcMap isn't taking advantage of when its doings things like a spatial join, how can I increase what ArcMap uses?

The optimization search results I am finding are from 2011 for before 64bit was an option.

[DanPatterson_Retired]

ArcGIS 10.3 ArcGIS 10.3.x for Desktop system requirements—Help | ArcGIS for Desktop

ArcGIS Pro ArcGIS Pro system requirements—ArcGIS Pro | ArcGIS for Desktop

compare functionality yourself to see if the new resources improve your situation

[BenPampel]

My system greatly exceeds the minimum requirements.

Is there a config file I can change or setting I need to increase to see ArcMap start using the memory that is just sitting there unused?

[V_StuartFoote · Accepted solution]

Ben Pampel​

SImple answer is that ArcGIS for Desktop is a 32-bit program. By default it will use 2GB, but that can be tweaked to use 3.2GB in its process space. That is it.

Out of process Python 2.7 Geoprocessing can be extended to use 64-bit address space.  The 64-bit geoprocessing extension installs a 64-bit Python 2.7 instance and replaces linkages to some of the 32-bit ArcPy libraries.

You can of course run multiple instances of ArcGIS for Desktop, but you have to handle the parallelization of your work flow.

Beyond ArcGIS for Desktop, you will have to work with ArcGIS Pro and its 64-bit Python 3.4 instance.

Or move to a non-Esri 64-bit implementation of GRASS or QGIS and the standalone OSGeo GDAL/OGR utilities.