Cube Processing Timeout Errors

Before finished work last week, I had to get one of our staging environments ready for some UAT, which involved refreshing the data warehouse and updating the cubes. Some of the cubes I have to manage are big. one cube in particular is really big.. over 2TB at last count. And managing cubes of such size can be challenging: After I had restored our data warehouse to the staging environment, rather than trash the data that was already loaded into the cube, I added the partitions to the cube that was already in the staging environment. This left the cubes state as partiallyProcessed (the historic data was already loaded, it was just the last months worth of runs that were unprocessed). I anticipated that processing these partitions would take overnight at least. So before I left work that evening I set the cube to run a process default that also ran a process update on the dimensions with processing affected objects (didn't want to lose all those aggregations!)