Operating Systems Concept Question Quick Help

PLEASE EXPLAIN THE FOLLOWING OPERATING SYSTEMS QUESTION AND SOLUTION TO THE QUESTION IF IT IS THE RIGHT SOLUTION.

Consider an index-based file system with the inode containing 64 indexes, 1 indirect index pointing to a disk block containing an array of direct indexes, and 1 2-level index in the usual way. Assume that each index takes 4 bytes.

Save your time - order a paper!

Get your paper written from scratch within the tight deadline. Our service is a reliable solution to all your troubles. Place an order on any task and we will take care of it. You won’t have to worry about the quality and deadlines

Order Paper Now

What is the maximum file size under this arrangement, if a disk block is 1024 bytes? Explain how do you compute this maximum size.

Solution:
An indirect block has 1024 bytes * 1 index/4 bytes = 256 pointers
So a file has at most 64 + 256 + 256*2 blocks and (64 + 256 * 256^2) * 1024 bytes.

How many disk accesses does it take to read one disk block at location 3000321 within a file, assuming no caching. Justify your answer.

Solution:
Block 3000321 is block number 2930, which means we have to read the inode, the 2-level index, a direct index, and the data block. 4 reads.