So much so that she runs away from home. Later in chapter 21 when Abraham is told that he had to put Hagar away because his son, Ishmael would bring the covenant into jeopardy. Hagar goes away and she has no more water. He knows her name. He knows where she is at.
Divine omniscience is a comforting doctrine.
You see God knows everything about us. He knows the struggles we are having. He knows everything that is to be known about you. But it is not only a comforting doctrine, divine omniscience is also a sanctifying doctrine. Job is a long book and difficult to work through.