[duskwuff]

In short:

Plotting is an compute- and IO-intensive process which eventually generates a ~100 GB block of data after a large number of read/write operations to that data. This is the part of the process that involves (and destroys) SSDs.

Farming is a slower process which is performed on those blocks of data, which involves occasional read operations on small sections of that data. The data blocks are typically transferred to slower bulk storage (like hard disks) for this.