In her Reddit AMA from 2012, Jemisin addressed this a bit:
The question was:
"How do you discover/generate names? Yours are always so evocative."
The answer was:
"For my protagonists, I just generally think a bit about the character and try to feel out syllables that fit. Nahadoth (Inheritance Trilogy), for example, felt like the sort of character who needed a long, ominous-sounding name. I tried two syllables, added another, then decided he needed more, and kept at it 'til I found something that felt right.
For less-important characters, I actually use a weird trick: I open any file on my hard drive, pick the last syllable of a random filename, pick the first syllable of another, and put them together. :)"
Now, I know she's talked about naming in the context of her construction and depiction of race, too. For example, her Dreamblood Duology is loosely Egyptian, and many of the characters have names that are more or less 'Egypt-y'. Characters not from the primary urban setting (tribal groups etc) have their own flavor to their naming conventions as well.
In her Broken Earth series, characters associated with the 'earth magic' group have appropriately mineral-themed names. To quote Wikipedia, civilians have a "given name followed by use-caste (rank of profession) followed by comm (community, town, or city). For instance Schaffa Guardian Warrant is a Guardian named Schaffa from the comm Warrant." To my knowledge, Wikipedia is accurate to the book.