In demand paging, is the data copied from disk into main memory, or it is transferred into main memory, leaving nothing behind in the disk?
Share
Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
In demand paging, is the data copied from disk into main memory, or it is transferred into main memory, leaving nothing behind in the disk?
Nothing is “moved”. Data is not a sheet of paper that can only be in one place at a time; it gets copied into memory, and afterwards it’s still on disk. Erasing it on the disk would mean overwriting it with different data, which takes additional time after doing the read.
It may eventually get overwritten, since the system will, of course, know what parts of the swap are still valid and required data, and which parts are considered “unused”.