How does this book compare with "Operating System Concepts" (aka the dinosaur book) ? I've read neither, but plan on teaching myself more about OS—after I complete "Elements of Computing" and "Computer Systems: A programmer's perspective." (hopefully in the next six months)
These are not books that you read as leisure, so probably one can't read it continuously. And I would recommend to have a personal project (or maybe one borrowed from another person) to test the concepts as you read. As people have social life and work, this 6 months time span seems acceptable.
About the books: I can't say about these two books because I learned it through a Brazilian book and I was applying it directly at my job (so I had to learn it faster).
I understand one has a job and stuff to do, but 6 months is 4320 hours. Let's say you waste 10 hours a day commuting and in your job, that's 1200 hours in 6 months. You have 3120 hours left to sleep and do whatever you want to do (obviously you have to factor out bed time), unless you have two jobs or children to raise, I think that's enough time to read at least six good size books. I myself am a book junkie, and I always make time everyday to read, because there are so many things to learn!
Not all books are created equal. I'm not the fastest reader, but if I can read a novel in a week or so by just reading 1-2 hours a night. Mathematics texts on the other hand may require as much as 1-2 hours for 1-2 pages (depending on how dense it is). CS texts tend to fall somewhere in the middle for me, but there's a reason that science courses tend to cover half of a book in a semester.